Carbide Inserts | Cutting Tools

Ingersoll Swiss-Style & Live Tooling Cutters

2009-04-17T15:07:00.000-07:00

Exclusive Swiss-Style & Live Tooling Cutters

Ingersoll announces exclusive integral collet tooling for their Hi-PosMicro indexable end mills and Chip-Surfer solid carbide tipped tooling lines!

Replace worn tooling with less downtime on your machine with .0005î axial and radial repeatability. Precision threads with simultaneous fit heads maximize the rigidity of your tooling application and reap the benefits of increased productivity with higher feed rates, better finishes and longer tool life.

The economy of indexability and higher feed rate capability of the Hi-PosMicro end mill tips allow you to exceed your previous throughput at lower costs. The versatility and wide range of Chip-Surfer tips complete your tooling requirements while offering premium carbide grades and coatings to be applied to the widest range of materials.

For more information be sure to contact your local Ingersoll representitive

BF Milling Cutter from Valenite

2009-04-12T09:54:00.000-07:00

BF Milling Cutter from Valenite

No burrs - Outstanding surface finish quality!

Great for Facing:

Aluminum
Steel
Cast Iron
Bi Metal

WHAT IS THE BF MILLING CUTTER?

Non-conventional milling cutter with a fully innovative design based on the broaching technology
Unique axial and radial positioning of the inserts which allows each of them to remove constant chip thickness
A single insert provides the quality of the machined surface
Maximum optimizing of the number of teeth.

What does this mean for you?

1. Facing with no deburring
2. Full control of the quality parameters of the parts
3. Outstanding surface quality
4. No insert adjustment
5. Reduction of the cost-per-part of 30%
6. 66% reduction in set-up time
7. High-feed machining with a reduced number of teeth

If you would like to learn more about the BF Milling Cutter or looking for Valenite Carbide Inserts, Google Keyword: Valenite Carbide Inserts

Quick Tips for Face Machining

2009-04-10T09:45:00.000-07:00

Very Cool 5 Face Machining Center

Here are three easy recommendations to help choose the right tool for high performance in face machining operations.

1. Choose the widest possible insert and tool, according to the cutting width and geometry to be machined.

2. Choose the shortest tool blade overhang, according to the maximum depth required.

3. Choose the tool range with the largest diameter depending on the initial grooving diameter required in the application.

Follow these easy steps, and you should be well on your way.

Thank you to Taegutec for providing these machining tips.

For Taegutec Inserts pricing online Google Keyword: Taegutec Carbide Inserts

Selecting Insert Width for Grooving

2009-04-07T09:38:00.000-07:00

Video of Grooving Operation

Here are some quick tips for selecting the best insert width for your grooving applications.

1. Insert width strongly affects strength

2. For most efficient machining, select the widest possible insert.

3. Chipbreaking range depends on the insert width.

4. A narrower width means better chipbreaking at lower feed rates

5. Wider inserts and stronger blades require higher forces adn higher feeds rates to achieve a frontal clearance angle.

Use these few basis tips to give yourself the best chance at success in your machining operation.

Thank you to Taegutec for providing these machining tips.

THREADING: TAPPING TITANIUM:

2009-01-20T18:23:00.000-08:00

Titanium and titanium alloys are most often found in aerospace applications due to its lightweight and high strength.

However, other industries are discovering the benefits of titanium as well. One of the more common alloys is Ti 6AL-4V. It is generally machined at a hardness ranging from approx. 28 to 37 Rc.

One the characteristics that makes titanium difficult to tap is its tremendous elastic memory. When tapping, the material closes tightly around the cutting tool, generating friction and heat, resulting in increased wear of the cutting edges. This material also easily work hardens.

To successfully tap titanium, a tap specifically designed with additional clearance to overcome the extreme elastic memory of the material is recommended.

Tap clearances would include extra back taper of the threads from the front to the back of the thread section, full radial clearance in the threads across the tap lands, and additional relief in the tap chamfer area.

All of these features are used to reduce friction and heat. In some cases, larger H limits might be required to overcome the shrinkage.

Premium grade materials are also used for heat and wear resistance. Obviously we offer these in our standard product lines.

Lubrication and proper pre-tapped hole size are vital to success. A compatible tapping fluid should be used that provides plenty of lubrication to reduce friction.

The drill should be selected to produce the largest hole size that is allowed by the thread class callout (2B or 3B).

Due to the additional clearances required on these tools, positive feeding of the tap is highly recommended.

Machining Titanium Tips

Inserts for Machining Titanium

Machining Aluminum

2009-01-16T18:03:00.000-08:00

V8 Engine Block Machining From Solid Aluminum

Aluminum is Inexpensive, Lightweight and is Formable at Cold Temperatures

Aluminum is one of the most common materials used in manufacturing strong, lightweight parts. PMF manufactures parts made purely of Aluminum alloys as well as parts made from two or more materials such as Stainless Steel and Aluminum.

Common Forms of Aluminum (in various tempers)
6000's, 5000's, 1000's, 2000's, 3000's, 7000's

Benefits of Aluminum

Inexpensive
Lightweight
Formable at cold temperatures

Considerations of Aluminum

Softness can lead to tearing
Low tensile strength (approx. 1/3 that of steel)

Applications of Aluminum

Military munitions
Aerospace
Microelectronics
Automobile parts
Many others

Looking for inserts for machining aluminum? Find them at pgsTools.com. Your choice

PCD Inserts for Aluminum

Carbide Inserts for Aluminum

What is Induction Hardening

2009-01-12T17:53:00.000-08:00

Definition: A widely used process for the surface hardening of steel. The components are heated by means of an alternating magnetic field to a temperature within or above the transformation range followed by immediate quenching. The core of the component remains unaffected by the treatment and its physical properties are those of the bar from which it was machined, whilst the hardness of the case can be within the range 37/58 Rc. Carbon and alloy steels with a carbon content in the range 0.40/0.45% are most suitable for this process.

What to do about Poor Thread Quality

2009-01-08T17:50:00.000-08:00

Often taps get the blame for poor thread quality or rejected threads and it is natural to look to the tap itself as the culprit. Actually, the tap is often the victim of a badly drilled hole. You can't produce a great thread out of a bad hole! Following are some issues and possible resolutions.

1. A dull drill will create a very rough torn hole. Expect poor or incomplete threads.

2. A reground drill must be perfectly concentric. The cutting lips must be of equal length and be ground to the same angles. Failure to create a concentric point will cause the drill to cut on one side more than the other and a crooked, bent hole will result making an attempt to tap that hole very difficult. This can also produce an oval egg shaped hole.

3. Castings sometimes have a tapered hole so the part will release easily. Threading requires straight walls and tapered walls are impossible to thread correctly.

4. Undersized holes are difficult or impossible to thread.

5. Holes that have had the surface work hardened by too high a temperature in the drilling process can become too hard to thread effectively.

6. Materials that shrink or close-in after drilling are undersized for tapping.

7. Holes too near welding or flame cut areas can become hardened and difficult to thread.
Bottom line, consider good hole quality as essential in producing quality holes and if you are having difficulty, dont forget to investigate the drilling process in addition to the tap.

Selecting Thread Mill Diameters

2009-01-04T17:39:00.000-08:00

Tips for Selecting Thread Mill Diameters

When producing internal threads, selecting the right thread mill diameter insures it will operate efficiently.

Thread mills are usually offered in several cutting diameters for a given threads per inch. Smaller diameters are used for small thread sizes, such as 3/8-16 NC.

A larger tool diameter could be used for producing a 3/4-16 NF. However, the smaller thread mill could be used to produce the larger 3/4-16 as well.

Generally, for coarser pitches (coarser than 14 TPI), selecting a cutting diameter no larger than 70% of the nominal thread size to be produced is recommended.

For finer pitches, the thread mill can be as large as 75% of the nominal diameter. Although the tool has radial clearances similar to end mills, if the tool diameter is too close to the thread diameter, the tool may rub, producing more heat that could result in excessive wear.

This rubbing may also distort the thread form affecting the thread angle.

The question is, should the largest thread mill that will fit the hole be used? The answer is, not necessarily!

For the greatest efficiency, smaller mills will remove more cubic inch of metal than a larger one, resulting in greater productivity.

There will be more clearance for the tool and more space for coolant and chips.

However, to optimize the tool, it will be rotating much faster, which may exceed the capability of the machine.

Also, the thread length on the tool may be too short for the thread depth required.

On the other hand, the larger diameter thread mill will minimize deflection, particularly on coarse thread series, but is more prone to rubbing and chip congestion.

Tips for Machining Stainless Steel

2008-12-02T08:14:00.000-08:00

Video of Teton Creek Mfg turning Stainless Steel

Here are a list of tips for machining stainless steel:

1. Use a tool that has higher thermal-conductivity
Low thermal-conductivity of stainless steels accelerates tool wear resulting from a decline in hardness of the cutting edge of an insert, this is due to heat piling up. It is better to use a tool that has higher thermal conductivity and with enough coolant.

2. Sharper cutting edge-line
It is necessary to utilize larger rake-angles and wider chip-breaker lands to reduce cutting-load pressue and prevent build-up on the edge. This will help provide better chip control to an operator.

3. Optimal cutting condition
Inappropriate machining conditions like extremely low or high speeds or low feeds can cause poor tool life due to work hardening of work pieces.

4. Choose an appropriate tools
Tools for stainless steel should have good toughness attributes, enough strength on their edge line (cutting edge) & a higher film adhesion.

Korloy offers three grades turning stainless steel:

For high speed turning of stainless steel - NC9020

For medium to low speed turning of stainless steel - PC9030

For medium to low speed milling of stainless steel - PC9530

For Korloy carbide inserts for stainless steel, please visit pgsTools.com to order online.

Hardware for Toolholders and Boring Bars

2008-11-17T08:59:00.000-08:00

Find Spare Parts for Tool Holders and Boring Bars

Lose a screw, lock pin, or clamp for your boring bar or toolholder? Wondering what the heck a lock pin or clamp is? Use the following guide to help you sort out what you may need in replacement parts for boring bar or tool holders. Find a definition of each component below the picture.

Here is a diagram (click on image to enlarge) of a Multi-Lock Tool Holder courtesy of Dorian Tool:

INSERT
Either conventional type or chipbreaker type may be used.

LOCK PIN
A solid locking pin for permanent locating of the insert.

SHIM SCREW
Reusable shim screw locks carbide shim into toolholder.

CARBIDE SHIM
Forms a firm seat for insert. Fastened to the shank, but easily replaceable. Protects against
damage to toolholder.

CLAMP
Maximum retention clamp is made of high alloy steel, heat treated. Broad clamp nose provides
positive clamping action. Clamp is positioned to allow for maximum insert retention, with or without chipbreaker.

CLAMP SCREW
Rugged Clamp Screw provides maximum clamping strength.

CHIPBREAKER
Solid carbide, for use when chip control is needed. Available in a range of standard chipbreaker
widths.

Most toolholders and boring bars accept generic shim seats, screws, clamps, and pins. This includes tools from Valenite, Sandvik, Kennametal, and Iscar. Check your manufacturers catalog to be sure of the replacement items part number.

PCD Tipped Carbide Boring Bars

2008-11-05T08:15:00.000-08:00

PCD Tipped Carbide Boring Bars

PCD Tipped Brazed Boring Tool. For Bore sizes smaller than 8 mm in diameter. PCD is brazed directly to a tungsten carbide shank providing a rigid boring tool capable of remarkable surface finishies and providing a high productive alternative to internal grinding.

For Bore sizes smaller than 8 mm in diameter, it is not possible to use PCD tipped cutting tool inserts. In order to put a PCD tip into the carbide insert, material must be removed. This makes the insert weak and prone to breakage when it is clamped into the boring bar.

At the same time, clamping of small inserts into small boring bars becomes progressively more difficult as the bore size reduces.Top clamps trap swarf and, in order to fit inside the bore, become too small to exert enough clamping pressure. Screw locked inserts, while leaving space for swarf, require sufficient material under the insert for the thread of the clamping screw.

These problems are overcome by using brazed tools. The PCD tip is brazed directly to a tungsten carbide shank providing a rigid boring tool capable of remarkable surface finishes and providing a highly productive alternative to internal grinding.

Valenite Carbide Inserts for Stainless Steel

2008-11-01T07:33:00.000-07:00

VALENITE INTRODUCES NEW TURNING GRADES FOR FINISHING, SEMI-ROUGHING STAINLESS STEELS

Valenite LLC has introduced two new tooling grades—expanding its targeted and application-specific lineup that allows users to better match machining operations and workpiece materials with tooling inserts for optimum production efficiencies, quality and economies. The new cutting technologies are the ValProTM VP8515 and VP8525 MT-CVD series of inserts. Both are being developed to augment the existing VP8535 grade and provide a complete range of turning capabilities for 304 and 316 stainless steels, Inconel and heat resistant alloys. The VP8515 is for finishing operations and the VP8525 is used for general duty semi-roughing/finishing. The existing VP8535 is for heavy metal removal tasks and roughing operations.

The VP8515 grade is set for high cutting speed (>200 m/min) at typical finishing

cut depths and has broad applicability with F5, M4, M6, M8, PM2, PM5 geometries. This grade is ideal for continuous turning of austenitic and duplex stainless steels at higher speeds providing reliable and predictable performance, with extended insert service life. Inserts using VP8515 grade have a thin yellow TiN outer coating for easy visual wear identification, an Al2O3 layer for thermal protection, a fine MT-CVD TiCN coating that helps to prevent flaking and reduces flank wear. Also incorporated in the tooling is a gradient area for added surface toughness, and a hard substrate offering greater resistance to wear and plastic deformation.

The TiCN/Al2O3/TiN coating is formulated specifically for turning of stainless steels and to resist sticking, notch wear and edge build-up, for enhanced hardness when hot.

The VP8525’s performance characteristics deliver high cutting speeds (>150 m/min) with mid- to large cutting depths...inserts have M4, M6, M8, R9, PM4, PM5 geometries to cover a myriad of cutting parameters. This grade is a basic choice for general duty M-class turning—continuous or intermittent cutting of austenitic and duplex stainless steels. These tools reduce the risk of plastic deformation and, like the VP8515, provide reliable performance and extended tool life. The VP8525 grade has similar coating technologies, layering and substrate construction as the finishing grade, including the TiCN/Al2O3/TiN coating for the efficient turning of stainless steels.

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Get carbide inserts or cutting tools for stainless steel machining at www.pgstools.com. PGS sells cutting tools and carbide inserts from Korloy, Taegutec, Valenite, Iscar and generic carbide inserts online at discount prices.

CNC Turning

2008-10-26T17:33:00.000-07:00

To produce hubs, rods, bushes, pulleys and shafts, CNC turning is utilized where the lathe generates materials after inserting the single cutter point in to the material turning. The procedure of cutting is executed through a cutting tool which is applied either parallel or at right angle to the axis, of work piece. The tool may also be fitted at an angle relative to the work piece axis for the machining angles and tapers. The work piece may be of any cross section, but the machine surface should be straight and tapered.

There are various shapes available in CNC like pointed, simple, radius with profile added with threaded surface, curve and fillet. CNC machining is more economical than the CNC milling for producing the actual form through CNC turning. The material used for CNC turning possesses various qualities like material of work piece should be firm and can be of solid plastics. For the short running procedure of the mill, arrangements or alternative machine should be kept. CNC turning reduces the cost by minimizing the design elements.

CNC turning procedure is done through applying pressure on the work piece or the weaker material to form the flexible shapes of the material. Sometimes through CNC, the cut surface is formed by applying the helical feed as it results in rotation. The cutting procedure through which the work piece is eliminated from a material block by the help of the rotation of the tool is known as CNC milling. The work piece can rotate in perpendicular or circular way to produce different shapes and sizes. The cutting tool generally rotates in the CNC milling at an axis in a perpendicular form on the podium to generate various structures.

Variety of shapes that can be formed through CNC milling is 3D or 2D and some compound structured material. CNC milling for short procedure is also very economical. It is utilized to make different parts of engine, multifaceted mechanisms, enclosures and mold and custom tooling.

Thus, is a very effective procedure to make various machine parts of various shapes which is very significant for running the machine.

Get carbide inserts or cutting tools for your cnc machines at www.pgstools.com. PGS sells cutting tools and carbide inserts from Korloy, Taegutec, Valenite, Iscar and generic carbide inserts online at discount prices.

Author: George Ure

Article Source: http://www.articlesbase.com/sales-articles/cnc-turning-488912.html

What is a tool bit?

2008-08-18T10:38:00.000-07:00

The term tool bit generally refers to a non-rotary cutting tool used in metal lathes, shapers, and planers. Such cutters are also often referred to by the set-phrase name of single-point cutting tool. The cutting edge is ground to suit a particular machining operation and may be resharpened or reshaped as needed. The ground tool bit is held rigidly by a tool holder while it is cutting.

Back Rake is to help control the direction of the chip, which naturally curves into the work due to the difference in length from the outer and inner parts of the cut. It also helps counteract the pressure against the tool from the work by pulling the tool into the work.

Side Rake along with back rake controls the chip flow and partly counteracts the resistance of the work to the movement of the cutter and can be optimized to suit the particular material being cut. Brass for example requires a back and side rake of 0 degrees while aluminum uses a back rake of 35 degrees and a side rake of 15 degrees.

Nose Radius makes the finish of the cut smoother as it can overlap the previous cut and eliminate the peaks and valleys that a pointed tool produces. Having a radius also strengthens the tip, a sharp point being quite fragile.

All the other angles are for clearance in order that no part of the tool besides the actual cutting edge can touch the work. The front clearance angle is usually 8 degrees while the side clearance angle is 10-15 degrees and partly depends on the rate of feed expected.

Minimum angles which do the job required are advisable because the tool gets weaker as the edge gets keener due to the lessening support behind the edge and the reduced ability to absorb heat generated by cutting.

The Rake angles on the top of the tool need not be precise in order to cut but to cut efficiently there will be an optimum angle for back and side rake.

Ref: http://en.wikipedia.org/wiki/Tool_bit

All About Cermet Inserts

2008-08-15T08:58:00.000-07:00

Cermet inserts can't quite replace the coated carbide inserts in heavy roughing operations with interrupted cuts, but in semifinishing and finishing cermet inserts outperform carbide. They permit a higher surface speed while maintaining an acceptable surface finish with good tolerance holding property and increased tool life. Because the cermet surface is slick it presents less friction to the chip flowing over the cutting edge which decreases the possibility of build-up when machining high alloy steels and cold-formed, low-carbon steels. Cermet inserts are available from several suppliers with a wide selection of pressed-in chipbreaker configurations or ground-in chipbreakers.

The cermet inserts work at surface speeds from 100 to 1000 sfpm. On multi-spindle-automatics, positive inserts made of cermets avoid build-up encountered when running carbide inserts with low surface speeds. Also cratering is reduced due to the low heat transfer properties of the cermet material.

The recommended cutting speed for turning unalloyed steel with approximately 200 HB is 250 to 800 sfpm with 0.002" to 0.015" fpr and depth of cut of 0.004" to 0.150". Alloy steels up to hardness of 300 HB will have satisfactory tool life when machined between 200 and 600 sfpm with the depth of cut and feedrate mentioned above.

Face milling with cermet inserts can be achieved with the same cutting speeds as turning with chip loads per insert from 0.002" to 0.12". Milling is performed dry, while turning can be dry or with coolants.

Up to the present, cermets are widely used in Japan with good results in reducing machining costs. They deserve a greater consideration for material removal in the United States.

Precision Cast Iron Machining

2008-06-03T08:55:00.000-07:00

Whether you’re making brake discs and flywheels in grey cast iron, or crank shafts and wheel hubs in nodular cast iron, there is always a successful solution.

Over the years there have been a number of CBN grades made available for machining cast iron with CBN. Most notably are DR-80 and DR-85. These grades are made for the following applications:

For rough and semi-finish turning, milling, grooving and boring of hardened ferrous and certain softer ferrous materials:-

Martensitic cast irons - Ni-hard - High chrome Chilled and heat treated cast irons
Fully hardened cold-work tool steels
Bearing steels
High speed steels (continuous cutting only)
Martensitic stainless steels
Cobalt and nickel based hard facing alloys
Fully pearlitic grey cast iron

DR-80 & DR-85 are high CBN content materials, diffusion bonded at the manufacturing stage to a tungsten carbide substrate.

DR-80 is (80% CBN) has a greater particle size than DR-85, (85% CBN). DR-80 is better for hardened steel, but DR-85 has better wear characteristics when machining cast iron with CBN, particularly when the stucture contains Ferrite.

For more information on machining with CBN Inserts
please visit David Richards Engineering UK or
David Richards Engineering US

Hard Turning with CBN

2008-06-03T08:45:00.000-07:00

CNMA 432 Quad Edge CBN Insert Shown

Hard turning with CBN will:

Reduce Grinding Investment
Increase Tool Life
Reduce Cost with Faster Cycle Times
Lower Tool Change Down Time Costs
Reduce Scrap Cost
Reduce By-Product Disposal
Extend Tool Life In High Production Hard Turn Applications
Increase Thermal and Mechanical Shock Resistance to Handle the Most Demanding Contouring and Interrupted Cuts

Hard turning requires switching from carbide to CBN inserts. It’s easier and more economical than one would expect. The major adjustment is working with much higher surface speeds.

Earlier posts that deal with CBN Insert questions:

CBN Insert Applications

What is PCBN?

Hard Milling with Ceramic Inserts

2008-05-27T07:20:00.001-07:00

Hard milling with ceramic inserts can help a mold shop to reduce manufacturing costs in several ways. First, a mold shop can replace several operations with one operation. Instead of machining, hardening and remachining, the use of ceramic inserts enables a shop to harden the steel first and then machine the part in the hardened form. This reduces manufacturing time and improves job tracking by reducing the number of times that you must set up and move a component through various manufacturing phases. Furthermore, roughing a hardened part with ceramic inserts also can eliminate expensive and time-consuming EDM operations, as well as the need to make one or more electrodes.

Second, ceramic inserts are capable of machining hardened steel at much higher speeds than conventional carbide cutting tools. Combine the higher operating speed with the proper feedrate and a healthy step-over and the shop can achieve some impressive metal removal rates. Another key factor in increased production rates when hard milling is the cutter density. Every additional tooth in a cutter increases the cross feedrate. Higher speed and more feed add up to lower cycle times and money saved.

Third, many times the surface finish achieved by rough milling with ceramics leaves less work for a finish milling operation, and reduces finishing and polishing time. Milling at relatively light feedrates in hardened steel with carbide usually leaves a good finish, but many times with ceramic inserts the rough finish is even better than the required finish. In some cases, additional milling, grinding and polishing can be eliminated, saving several hours of manufacturing.

Cylinder Boring with CBN or PCD Inserts

2008-05-14T08:39:00.000-07:00

Boring out cylinders to accept oversized pistons or sleeves has long been a common practice in the engine rebuilding business. Boring allows worn blocks to be salvaged, and stock cylinder bores to be enlarged for more displacement. More recently, boring is also being used to install special cylinder liners with hard surface treatments in high performance racing engines. The hard liners almost eliminate ring and bore wear so the engine can run race after race with no increase in bore clearances blowby.

Like most other machine tools in today's shops, the equipment used to bore engines is also evolving to keep pace with changes in engine technology and the aftermarket. Small shops want equipment that is versatile and can do more than just bore holes. For this end of the market, combination boring/milling machines have become popular. At the other end of the spectrum, production engine remanufacturers (PERs) want equipment that works harder, works faster and requires less operator input. For this type of user, automated high speed boring equipment provides the needed boost in productivity and quality.

Tooling has also been improving. The latest generation of coated carbide inserts provides longer life and better cutting action. For high speed boring, polycrystaline diamond (PCD inserts) provides the longevity needed for this type of operation. The speed at which the boring bar turns has a significant impact on tooling life. High speeds just kill the bits unless you use a PCD or cubic boron nitride (CBN inserts) type of insert. The high speed boring machines that go up to 1,500 rpm need these type of inserts.

Face Grooving Inserts and Tools - Korloy MGT Series

2008-04-29T04:19:00.001-07:00

Horizontal Type MGT Face Grooving Tool

Vertical Type MGT Series Face Grooving Tool

Korloy MGT Face Grooving Inserts or MGT tools, have double ended cutting edges, provide economic tooling cost. More so than conventional single ended type tools.

Insert grades available for the machining of carbon steel, alloy steel, stainless steel, and cast iron.

To cope with the increased needs for face grooving and boring of various material, the newly designed chip breakers are able to acquire good chip control.

Korloy Face Grooving Inserts provide various holder line-ups to expand your option, while adding more features and benefits.

Inserts Shown Below
MFMN300 (Cutting Width 3mm)
MGMN400-M (Cutting Width 4mm)

Recommended Cutting Conditions (Speeds and Feeds - Workpiece Material)

If you have questions, would like to purchase, and trial the MGT Face Grooving Inserts please contact us at: sales@pgstools.com

Sumicrystal Blanks - Synthetic Single Crystal Diamond

2008-04-23T05:24:00.000-07:00

Sumicrystal Blanks - Synthetic Single Crystal Diamond

Sumicrystal PD/PDX Dresser Blanks
2 pictures above

Sumicrystal UP Cutting Tool Blanks
2 pictures above

What is this stuff?
Synthetic Monocrystalline Diamonds: Perfectly flat, defect free synthetic diamonds- Monodie-100 and Monodie-111 from DeBeers, U.K. and Sumicrystals from Sumitomo Electric Industries, Limited., Japan-are used for specific customer requirements.

What is a PD Dresser Blank?
The Sumicrystal PD dresser blanks are single crystal diamonds processed into the shape of a long, thin prism. They provide automated and high precision dressing through reliable performance and long tool life.

Ok, now what about the UP Cutting Tool Blanks?
The Sumicrystal UP cutting tool blanks are just that...cutting tool blanks. They were developed by Sumitomo Electric to provide high performance and reliability for high precision cutting tools. They work well in ultra-precision machining processes, for machining products such as memory discs and polygon mirrors.

Now that I know, where can I get it?
Interesting that you should ask. The pictures above are tools that are available. If you are s, interested in purchasing these tools, please contact us a sales@pgstools.com.

Ceramic Inserts vs. CBN Inserts

2008-04-14T08:46:00.000-07:00

CNMA CBN Insert (shown in picture above)

VS.

CNGA Ceramic Insert (shown in picture)

An important criterion for the economical application of cutting tools is their life in relation to the metal removal rates, especially with two materials such as ceramic and CBN. The latter is much more expensive. Thus, comparison of tool wear becomes most important.

The two materials show marked performance differences in both size and surface finish in roughing, interrupted, and finishing cuts. In comparison to grinding, however, both materials will achieve much higher metal removal rates.

CBN will out-perform ceramic in interrupted cuts. With depth-of-cut of 0.060 inch to 0.120 inch and a speed of 350 sfpm with 0.010 to 0.020 inch feed per revolution, ceramic often will fail when entering the interruption. With CBN, a tool life up to 20 minutes can be achieved with a half-inch round insert, under the above conditions. Flank wear in interrupted cuts is more irregular than in continuous cuts and can shorten tool life. Solid CBN inserts have greater flank wear resistance and are superior to ceramics for roughing, especially where the turning has interrupted cuts.

For finishing cuts where small depths of cut and low feed rates are required to achieve superior surface finishes, CBN inserts cannot equal the tool life of ceramic inserts. Under these conditions, the ceramic insert has less than half the flank wear of CBN after 30 minutes cutting time.

Considering that CBN is ten times more costly than ceramic for the same size and geometry insert, CBN economically can be justified only for machining heat treated steel in those situations where ceramic fails completely or breaks down before finishing the workpiece.

excerpted from gardner article

A Post About Absolutely Nothing

2008-04-13T19:06:00.000-07:00

Ok, so in the title it says that on from time to time there would be an occasional rant about nothing. I haven't faithfully held my end of the bargain on that one. Therefore folks, here you go, a rant about nothing.

Over the weekend at our church, I had the pleasure of playing my acoustic guitar with some very talented musicians, in front of a few thousand people. I tell you what, in my life, this was up there with being one of the more difficult thing I've ever had to do. My attempts at public speaking, while enjoyable would be number one, but after time that becomes less nerve inducing. But doing something that has always been a hobby, in front of a large group of people was enough to put the sweat glands into overload. On more than one occasion it seemed like they had turned up the heat, then I realized, oh, its just me.

I am grateful that I was given the opportunity to share the talent that I have been blessed with. I was feeling pretty good about my guitar playing skills, until I came across the following video, shown below. I know now that I still have a long way to go. Hope you enjoyed the rant, now enjoy a truly talented musician.

Regards.

An Introduction to Knurling Tools

2008-04-13T17:37:00.000-07:00

Thanks to V. Ryan © 2003 For Pictures For More Visit
http://www.technologystudent.com/equip1/knurl1.htm

An Introduction to Knurling Tool

Author: John Russel

A knurling device is used in combination with a lathe to stamp the ends of metal tubes and other shafts. The stamped ruts might also act as hand grips for the user or superior grip for rubber and the plastic covers. The knurling tool itself comprises of various rotary cutters that are held against the metal shaft as it turns on the metal lathe at a moderately slow speed (500 rpm on average). Turning is a technique by which cylindrical pieces of metal lathe or wood are spun in place by a variable-speed electric motor. As the piece spins, a variety of cutting tools could be placed against it to take away fabric or cut shapes. A knurling tool falls among an engraver and an embosser.

There are usually three shapes created by most knurling tools - straight lines, slanting lines and a diamond pattern. Knurling tools do come in different range of sizes and amazing designs, depending on the basis of the piece. The diamond pattern is mainly familiar with hand grips as it generates the most grips among a user's hand and the shaft. Diagonal and straight knurls are usually used to give additional traction to an outside handle or other connective piece. In order to generate a knurl pattern, the metal lathe should hold the metal piece entirely straight - a condition machinist call 'true'. As the lathe begins to roll, a particular holder for the knurling tool is attached to the perform table.

The knurling tool itself is fixed into the lathe and cautiously directed to the turning piece with a tiny crank. Since knurling is extremely a rough process, the machinist must use a liberal supply of machine oil on the rotating shaft. A knurling tool hardly ever makes a complete imprint the first time it is pressed against the shaft. Machinists usually make several passes with the knurling tool, allowing the individual cutters to make small bites into the metal. A knurling tool is best compatible for softer metals such as aluminum or normal grade steel. Hard metals such as titanium would most probable ruin the tool before any embossing could take place.

Article Source: http://www.articlesbase.com/sales-articles/an-introduction-to-knurling-tool-226481.html

About the Author:
John Russel is a Copywriter of Lathe chucks. He written many articles in various topics. For more information visit: Chuck manual contact him at aworkholding@gmail.com

Benefits of Carbide Cutting Tools

2008-04-04T12:44:00.000-07:00

Carbide Cutting Tool in Action

Benefits of Carbide Cutting Tools

Author: John Morris

In every machining system, one simply can't ignore the important role that cutting tools play. Oftentimes, the quality of a finished product would rely on the quality of the cutting tools. The quality and the performance of cutting tools would also directly affect a machining system's overall productivity. It is because of their importance that manufacturers would take into consideration several criteria before eventually buying a piece of cutting tool for their machining system. Included in these criteria are the tools ability to last long under rigorous operating conditions and their capability to perform at very high speeds. Also important is the tool's resistance to wear and tear, including resistance to breakage, edge and flank wear, cratering or top wear, chipping, built-up edge (BUE), deformation, and thermal cracking.

1. Kinds Of Tools

As the demand for better cutting tools increase, cutting tool suppliers also continuously develop products that can pass manufacturers' demands. Through the years, a lot of materials for the manufacture of cutting tools have been experimented upon; some have passed the standards while others were simply dropped. Today, there are only two types of cutting tools heavily favored in the machining industry: high speed steel (HSS) cutting tools and carbide cutting tools; and it seems that carbide cutting tools have slightly overtaken the other in popularity. So, what advantages do carbide cutting tools have over their HSS counterparts? Considering their lead in popularity, it is clear that the benefits of carbide cutting tools outnumber that of HSS cutting tools. And we'll understand these benefits better if we know what carbide really is.

2. What is Carbide?

In chemistry, carbides refer to any group of compounds made up of carbon and one other element that can be a metal, boron, or silicon. There are actually many compounds belonging to this group, among the more popular of which includes:

- Calcium Carbide
- Aluminum Carbide
- Silicon Carbide
- Tungsten Carbide
- Iron Carbide

3. Industrial Uses of Carbide

In the 20th century, carbides have been used for a lot of industrial applications. Carbides used in industrial applications are often called cemented carbide products and are classified in three major grades:

- Wear grades

Used primarily in dies, machine and tool guides

- Impact grades

Higher shock resistance carbide products used for dies, particularly for stamping and forming

- Cutting tool grades

Carbide tools used for cutting

4. Carbide Cutting Tools

Cutting tool grades of carbides are further subdivided into two groups: cast-iron carbides and steel-grade carbides. As their name implies, cast-iron carbides are specifically made for cutting cast-iron materials. These carbides are more resistant to abrasive wear, protecting the carbide cutting tool from edge wear due to the high abrasiveness of cast-iron. Steel-grade carbides, on the other hand, are specially made to resist cratering and heat deformation that may be caused by the long chips of steel on higher cutting speeds. Whichever grade of carbide is used in a carbide cutting tool, the main carbide material used in its manufacture is tungsten carbide (WC) with a cobalt binder. Tungsten carbide is well known for its hardness and resistance to abrasive wear. Cobalt, on the other hand, is used to further toughen the tool's surface.

5. Other Variants

Aside from tungsten carbide and cobalt, other alloying materials are added in the manufacture of carbide cutting tools. Among them is titanium carbide and tantalum carbide. Titanium carbide helps the carbide cutting tool to resist cratering while tantalum carbide can reduce heat deformations in the tool. Also commonly used in the cutting industry today are coated carbide cutting tools. Aside from the basic carbide materials, titanium carbide, titanium nitride, ceramic coating, diamond coating or titanium carbonitride are used as coating materials. The different coating materials aid the carbide cutting tool differently, although they are generally used to further toughen the cutting tool.

6. Benefits of Carbide Cutting Tools

- Toughness
- Exceptional resistance to abrasion
- Superior wear resistance
- Resistance to cratering
- Resistance to thermal deformations
- High modulus of elasticity
- Chemical inertness
- Torsional strength twice that of HSS
- Compressive strength

Article Source: http://www.articlesbase.com/technology-articles/benefits-of-carbide-cutting-tools-16013.html

PCD Insert Tooling for Plastics

2008-04-02T12:37:00.000-07:00

Plastics and reinforced plastics can be machined with PCD Inserts and PCD tooling.

The general perception is that plastic materials are easy to machine. However, soft plastics are not always so stable, and the machining process, which always generates heat, can affect dimensional and material properties like surface texture and colour, if the correct cutting tool is not applied.

PCD tools are particulary effective on abrasive plastics where plastics are reinforced with carbon fibres (CF) or glass fibres (GF).

For more information on machining plastics with PCD insert or PCD tooling please contact the experts at:

David Richards Engineering Limited

David Richards Engineering Corporation

Machining Rolling Mill Roll with CBN

2008-03-31T04:12:00.000-07:00

White Iron Roll Machining

Application Example:

Component: Rolling Mill Roll (1 metre diameter x 3 metre long)

MachineTool: Craven Centre Lathe

Material: Chilled Cast Iron ( 55 Hrc)

Operation: Turning

Depth of Cut: 2 mm (0.08")

Insert: RNMN 120300T DR-100

Surface Speed: 100 m/min (330 ft/min) cutting without coolant

Feed Rate: 0.2 mm/rev (0.008"/rev)

Surface Finish: N/A

Tool Life: Average 40 minutes contact

Comments: Semi-finishing for grinder � machine not powerful enough for bigger cuts or feed rates

DR-100 has a high CBN content, 99%, and is supplied as solid I.S.O format indexable inserts for top clamp tool holders. PCBN cutting tools machine hardened steels with apparent ease because, using relatively high

surface speeds, heat is generated at the point of cutting so the PCBN tool cuts locally softened material.

For more information on machining with CBN Inserts
please visit David Richards Engineering UK or
David Richards Engineering US

Using Coolant - CBN Inserts - Interrupted Cutting

2008-03-29T09:29:00.000-07:00

Although most of the heat essential for efficient cutting exits with the chip, any increase in the temperature of the component will make accurate measuring difficult. Coolant can be used to reduce this effect.

Coolant can be used to drive away any swarf which might interfere with the cutting edge, particularly in boring operations. Coolant can help reduce vibration, especially where rigidity is limited.

Where interrupted cutting with CBN inserts occurs, coolant should not be used as this will thermally shock the CBN tool as it comes out of the cut, resulting in premature failure. Although interrupted cutting with coolant will never improve tool life, it is possible to use coolant machining hardened stee l with DR-450 CBN inserts and coolant can be used when machining cast iron with CBN, that is not hardened, under all conditions.

For more information on machining with CBN Inserts
please visit David Richards Engineering UK or
David Richards Engineering US

Cnc Milling: a Versatile Process

2008-03-20T05:33:00.000-07:00

Author: George Ure

Computer Numerical Control (CNC) Milling is a common type of automated machining process. These machines are specially used for drilling, facing, and turning functions. Their classification is based on the number of axes they have. These axes are labeled as x and y for the two horizontal directions while z is for vertical movement. CNC milling is a cutting process that is used to remove metal or plastic from a block of stock material by the rotating action of the tool. The tool is moved in three (or more) directions to get the desired cut of the material.

CNC Milling machines have been programmed with the help of a set of commands called G-codes. These codes are special CNC functions in alphanumeric format.

The cutting tool is usually rotated along the axis, which is perpendicular to the table where the material to be cut is placed. There are different cutter shapes (called milling bits) such as round (ball end), square, and angled.

Advantages of CNC Milling

A large variety of 2D and 3D shapes are possible. Complex shapes from rod, block, or sheet material can be created and is cost effective for short runs.

Specifications for CNC Milling

• Rigid materials such as metals and hard plastics are used.

• Alternative machines for 2D sheet shapes that include Laser Cut, Turret Punch and fixed punch are used.

• CNC Milling requires software program tooling or work holding jigs.

• To contain costs avoid large variations in work piece height and avoid thin walls.

The CNC Machining centers are computer controlled vertical mills which can move the spindle along the Z-axis. When the machine is used in combination with conical tools or a ball nose cutter it improves the milling precision without affecting the speed thus providing an economical substitute to flat surface job that requires hand engraving.

During the milling process pressure is applied to the material therefore it is better to avoid weak shapes, long thin shapes, or ones with thin walls. CNC milling offers a cut surface that has a visible pattern due to the rotation and movement of the cutter.

eMachineShop offers you information about a vast number of products and machines and CNC Milling machine is one of them. A unique online CMC provider allows you to design and even order custom CNC machined parts. Visit the site www.eMachineShop.com to get details about these and other services. While you’re there, don’t forget to download the company’s free 3D CAD software which makes designing CNC milled parts a snap!

Article Source: http://www.articlesbase.com/business-articles/cnc-milling-a-versatile-process-320816.html

About the Author:
George is a well known author who writes on the topics related with CNC Milling , waterjet cutting and Free CAD Software for the site www.emachineshop.com.

Machining Engine Gear Example

2008-03-08T17:35:00.000-08:00

Welcome to a new section of carbideinserts.blogspot.com. Our focus with these blog posts will be to provide application examples with insert type, speeds and feeds, to hopefully give you a baseline and to help you with your own machining applications. We will add these machining tips on a regular basis, so check back often!

Component Description: Engine Gear
Material: Low Carbon (0.2% C) Cr-Mo Alloy Steel
Cutting Paremeters: SFM=984
Feed=.010ipr
DOC=.051"
Wet cutting. Face & External Turning, continuous cut.
Recommended insert: CNMG 432ML TT5100

PCD Insert Machining Dont's #1

2008-03-02T15:19:00.000-08:00

PCD inserts are not recommended for the machining of Iron, Cobalt, or Nickel alloys. In the presence of these metals and the heat and pressure created by cutting, diamond is encouraged to revert to the metastable carbon form: graphite. It is possible to use PCD inserts to machine some stainless steels and other highly alloyed materials, which have the iron, cobalt or nickel tied up in a non-reactive state. Even so, these materials should be machined at low cutting speeds and feeds with coolant to reduce any heat generated.

What is PCD (Polycrystalline Diamond)?

Machining Cemented Carbide

2008-02-29T09:27:00.000-08:00

This blog entry focus is on machining the following:

Cemented carbide with a Co content of less than 17%:

1. First choice for machining is CBN
2. Should use a round cbn insert
3. The insert should have a chamfered cutting edge
4. Machining with coolant is recommended
5. Chamfer the workpiece at entry and exit point.

Should you require further assistance in choosing an insert or pricing. Please contact the experts at David Richards Engineering.

Hard turning with CBN - Finish Machining

2008-02-24T15:36:00.000-08:00

Through hardened En31 Bearing Steel Machining

For finish-machining of hardened steels and certain softer ferrous materials:

Surface and through hardened steels

High speed steels

Bearing steels

Hot - work die steels

Cold - work tool steels

Grey and chilled cast iron

Sintered Irons

CBN cutting tools machine hardened steels with apparent ease because, using relatively high surface speeds, heat is generated at the point of cutting so the PCBN tool cuts locally softened material. The heat is carried away by the swarf, which becomes brittle and harmless, and the PCBN tool, which has a high co-efficient of thermal conductivity. If a light cut is required, however, a tool with a high CBN content conducts too much heat away from the shear zone and the conditions for efficient machining cannot be achieved.

DR-50 & DR-50N have a low CBN content and the individual CBN particles are isolated within a ceramic matrix. This gives the materials a lower thermal conductivity and greater wear resistance in finish cutting operations.

Low CBN tools can therefore keep sufficient heat at the cutting point to enable the optimum cutting conditions to be achieved when a light cut is taken. In most cases, even when very light cuts are required, low CBN tools employ negative rake geometry to provide a strong edge. Due to the nature of cutting, however, cutting forces are still very small. Low CBN can be used to provide a productive and cost effective alternative to grinding.Tolerances achieved are comparable but machining time can be dramatically reduced.

DR-50 has a low CBN content and is designed for finishing and semi-finishing applications where grinding with conventional abrasives proves time consuming or difficult. DR-450 is tougher and performs well over severe interruptions.

UK Customers
CBN Inserts for finishing

US Customers
CBN Inserts for finishing

Machines for hardturning

Thanks to David Richards Engineering Limited

Turning Carbon Fiber Composites

2008-02-21T09:43:00.000-08:00

What's the best insert for turning carbon fiber composites?

At first it might seem that machining fiber-filled composites with hard cutting tools would be a recipe for disaster. Developers of cutting methods and tools for composites face all kinds of problems. A composite's fiber layers can delaminate from the machined surface; the fibers or other hard reinforcements are abrasive and reduce tool life considerably; and the combination of hard and soft materials that make up a composite complicates the best choice of tool and machining parameters.

What do I use then?

Diamond will interact with carbon in ferrous materials, so its use is largely restricted to nonferrous workpieces. Today, the automotive industry is the major user of diamond tools in machining components made of aluminum-silicon alloys--in particular the 300 series of aluminum alloys. Major applications for silicon-containing aluminum materials are in pistons, engine heads, blocks and manifolds, wheels, and transmission parts. Other significant applications for diamond tools are in machining graphite, carbon-carbon (C-C) composites, metal-matrix composites (MMC), and fiber reinforced plastics (FRPs).

Where do I find the tools?

PCD Inserts
Diamond Coated Inserts

What about speeds and feeds?

Speeds and feeds for machining composites with pcd

special thanks to SME for information on machining composites

What is Cermet?

2008-02-20T09:24:00.000-08:00

What are cermet inserts?

Of uniform structure and composition, Cermet is composed of solid titanium carbide (TiC) and titanium nitride (TiN) with a super-alloy metal binder. Cermet has a low friction coefficient which eliminates built up edge and improves surface finish. Its high resistance to thermal deformation and its low conductivity make higher cutting speeds possible and result in lower flank wear and edge cratering. Its high degree of hardness and toughness, with resistance to oxidation, extend tool life.

Inserts for difficult materials

2008-02-20T07:00:00.000-08:00

Superalloys are hard; some grades of titanium are machined at 330 Brinell hardness. With conventional alloys, cutting zone temperatures greater than 2,000[degrees]F soften molecular bonds and create a flow zone for chips. In contrast, the heat resistance that makes HRSAs so desirable keeps them hard throughout the machining cycle.

HRSAs also tend to work-harden as they are cut, notching cutting inserts to premature failure. The difficulty cutting HRSAs is compounded where unpeeled stock is covered with abrasive, knife-edged scale that wears cutting edges down even more quickly.

Given their machining difficulty, superalloys are cut slowly. For example, Inconel 718 is milled for brake keys with Sandvik GC2040 grade carbide inserts at 200 sfm. Turning speed for the same alloy with Sandvik 7020 CBN inserts in an outside turning/facing application is 260 sfm. By comparison, uncoated carbide inserts typically cut tool steels at 400 to 800 sfm. Feeds for HRSAs are generally comparable to those used when machining tool steels.

The choice of cutting inserts to machine HRSAs depends on the material and the workpiece. Carbide inserts with positive rake geometries will cut thin-walled HRSA stock effectively. However, thick-walled parts may require ceramic inserts with negative cutting edge geometry to create a more productive plowing action. While dry machining is preferred in most difficult materials to maintain uniform edge temperatures, titanium requires coolant even at very low speeds.

by Wayne Mason

Technical Tips for Drills

2008-02-19T13:53:00.000-08:00

Here are links for technical information on drills.

The links cover the following:

Speeds and Feeds for Drilling
Speeds and Feeds for Deep Hole Drilling
Feed Rate per Revolution for drills
Troubleshooting drills

For more information please visit www.toolinghouse.com for drills, taps, and carbide endmills

New Products

2008-02-19T07:56:00.000-08:00

PGSTools.com is proud to announce the addition of the following products:

Iscar carbide milling inserts

and

Valenite carbide inserts

Most tools are in stock and ship same day out of Michigan.

Be sure to check out Valenites new inserts for stainless steel

VP8515 and VP8525

VP8515 is for finishing operations, while the VP8525 is for semi-finishing/roughing operations.

Carbide Inserts by Style

2008-02-18T09:14:00.000-08:00

An answer to a recent email question I received, here are some of the most common style carbide inserts:

CNMG carbide insert

CNGA ceramic insert

DNMG carbide insert

DNGA ceramic insert

TPG carbide insert

TPG ceramic insert
VNMG carbide insert
VNGA ceramic insert

These links will take you to tools by Taegutec, Korloy, Kennametal, and generic carbide inserts.

Wow

2008-02-06T16:04:00.001-08:00

There is a lot of snow! Baby It's Cold Outside

This Song Says It All!

Carbide Insert Identification Chart

2008-02-06T15:47:00.000-08:00

Carbide insert identification chart is now available at www.pgstools.com. This chart is helpful for identifying inserts without a home.

The insert identification chart is located here:

Carbide Insert ANSI Designation

CBN Cutting Tools for Grooving

2008-02-05T19:01:00.001-08:00

Hard part grooving can be a difficult process without the correct tools. CBN cutting tools for grooving can ease that process. During heat treatment, many features of machined components suffer distortion. If the position or dimensions of a groove are critical to the performance of a hardened component, David Richards can offer a simple solution to this problem - ‘Hard Grooving’. Based on the Top Notch system, David Richards supply grooving tools in a wide range of sizes from 0.5 mm width upwards. David Richards supply tools for circlip and ‘O’ring grooves with controlled corners or full radii, either full form for plunging or undersize for profiling.

Using such surface speeds typical for turning, grooves are machined at low feed rates (0.01 / 0.05 mm/rev). The low feed rate ensures that the swarf is very weak and brittle, decreasing the likelihood of it breaking the tool. Where there are no interruptions to the cutting path, coolant should be used to aid evacuation of the swarf and ensure that the component remains at a stable temperature for ease of measuring. If the cutting path is interrupted, an air blast will serve the same purpose without the risk of thermally shocking the PCBN tool.

If practical, it is better to finish a groove that has been pre-formed at the soft stage. This ensures uniform hardness around the groove and maintains the structural integrity of the component. However, if it is acceptable, satisfactory results are achieved grooving through a hardened layer into the core material. Successful applications include grooving case hardened (58 / 63 HRc) splined shafts and gear teeth, internal circlip grooving hardened EN31 (58 / 60 HRc)
bearing components, and producing profiles in the face of D2 tools steel tools using Full radii face grooving tools. All operations that would be time consuming and difficult to grind.

Whilst the Top Notch system offers an ideal base for most grooving tools, other systems have been employed with excellent results.

It naturally follows that, since David Richards can produce tools for ‘Hard Grooving’ full and partial form cbn threading tools, both external and internal, are available for ‘Hard Threading’. Where the pitch of the thread is large, or the diameter of the component is small, it must be remembered that the feed rate required, at the required surface speed for ‘Hard Turning’ will be relatively fast. But, producing a 90 mm diameter internal stub Acme thread 150 mm deep,
with a 6 mm pitch in 58 HRc Ni-Hard iron, at 120 m/min from blank bore, though somewhat exciting, proved a major cost saver.

To purchase CBN Grooving Inserts please visit

www.pgstools.com

Machining Soft Steels with CBN Inserts

2008-02-04T09:39:00.001-08:00

Finding it difficult to machine soft steels with cbn inserts? I would suppose that soft steel is relative, so generally speaking, cbn inserts will machine steels from 45-65 HRc. For soft steels (the ones on the lower end of the 45-65 HRc), the lower you are on the hardness scale, the faster you will want to machine the material.

CBN needs heat to cut at its fullest potential. A quick lesson: CBN generates heat in the shear zone, thus locally anealling the material, cutting it as if it were soft.

If you are having trouble with turning using CBN inserts or PCD inserts, please call to discuss your application with David Richards Engineering or email to sales@drengus.com

Purpose and Use of the Cut-Off Tool and Holder

2008-02-02T08:53:00.000-08:00

After completing a part in the lathe it is frequently necessary to separate the part from the excess material used for chucking. This operation is best accomplished with the use of a cut-off tool or "parting tool" as it is sometimes called. The Cut-off Tool and Holder consists of a very slender high speed tool steel cutting blade mounted in a special tool holder. The thinness of the blade (.040") enables it to feed into the part quite easily and at the same time minimizes the amount of waste material. The turning speed for parting should be approximately one half the normal turning speed for any given material. One word of caution; never use a parting tool on a part mounted between centers. The part may bind on the cutter and result in a scrapped part or a broken cutting tool.

Parting off material (free machining) over a 1.00" (25mm) diameter will always present problems on a machine of this size.

Always try to lay work out so the cut-off tool is used as close to the spindle as possible. Set blade height by sliding the blade in its slot in the tool holder. It should be set so the tip is aligned with the centerline of the part being cut. An unusual diameter may require a shim to be placed under the front or rear of the holder to accomplish this.

NOTE: ALWAYS USE CUTTING OIL WHEN USING THE CUT-OFF TOOL. The cut will be made much smoother, easier and cooler.

Speed should be slower than normal turning speed and feed rate should be a little heavy so the chip will not break up in the slot. If speed and feed are correct, there will not be any chatter, and the chip will come out as if it were being unrolled. Coolant (cutting oil) plays a major roll in this occurring properly.

If the tool chatters, first check to see if the work is being held properly. Then decrease speed (RPM) or increase feed rate or both. Once the blade has chattered, it leaves a serrated finish which causes more chatter. Sometimes a serrated finish can be eliminated by turning the spindle off, adding a liberal amount of cutting oil, bringing the blade up so there is a slight pressure on it without the spindle turning, and then turning by hand or as slowly as possible with the speed control.

BY: Joe Martin

Where to use ceramic inserts and silicon nitride inserts

2008-02-01T08:26:00.000-08:00

All Irons... use silicon nitride in all applications...turning, boring, milling & facing. Use for roughing, semi-roughing, semi-finishing & finishing applications. Generally speaking, silicon nitrides can be used in all iron applications.

All Irons... use the black (CC-20) and/or white (CC-10) ceramic on semi-finishing & finishing applications. They are less costly and harder than silicon nitride (more abrasion resistant & longer lasting).

Steels below Rc58 in hardness... use the black (CC-20) and/or white (CC-10) ceramic in almost every semi-finishing & finishing applications. They can even cut with mild interruptions. If your customer isn't using CC-10 & CC-20 on almost every finishing application, he's losing money.

Steels above Rc58 in hardness... use the black (CC-30) for finishing applications, especially to replace grinding. You can also use silicon nitride for roughing.

Aerospace Metals... Inconel, Hasteloy, Waspeloy, Renee, Etc. For roughing or finishing use CC-5477 Silicon Nitride specifically designed for these materials.

Click on the link below for tools:

Ceramic Inserts

Carbide Insert for Turning Wood

2008-02-01T03:43:00.000-08:00

We have found that this insert performs quite well for turning wood. There are two choices available for chipbreakers. In the first picture is the "TA" and the "HA" is in the second picture. Each one serves a different purpose, so read carefully. Both inserts are from Korloy. These inserts are available in packs of 2. For pricing on carbide inserts for turning wood: www.pgstools.com

Recently added to the collection are these carbide inserts for cutting wood:

http://www.pgstools.com/servlet/the-Carbide-Inserts-cln-Wood-Cutting/Categories

Machining M2 - Speeds and Feeds - Boring Tip

2008-01-31T08:43:00.000-08:00

Recently came across an application machining M2 with CBN Inserts. Thought it was worth sharing. Here is the breakdown:

Job: Finish Bore M2

Material: M2

Hardness: 58-62 HRc

Insert: CDCD51 CBN Insert - Circle $150/ea

Depth of Cut: .002" per side

Feed: .005" per revolution

Surface Feet per Minute: 400 SFM

The Problem: Inconsistent tool life and insert would chip after two parts

Solution:

I am sure that some may have already figured this out based on the radius size of the insert compared to the feed rate, but for those not in the know, here is the fix:

Change to:

Insert: CDCD 51 T DR-50 Insert $50/ea.

Surface Feet per Minute: 300 SFM

Feed Rate: .003" - .004" per revolution

Depth of Cut: Keep the same

Result: Increased tool life by more than 15x to 30 parts per edge and saved over $100 per insert.

Disadvantages of Diamond Coated Inserts

2008-01-30T07:40:00.000-08:00

Probably the main weakness of thin-film diamond-coated inserts is lack of toughness. CVD diamond films are brittle when deposited on low cobalt substrates. These inserts are not always robust enough to endure high mechanical shock. They are not always the best choice for heavy metal removal and interrupted cutting.

As with most coated inserts, thin-film diamond-coated inserts are "throwaways." They cannot be reground.

Predicting the performance of CVD diamond inserts is still somewhat uncertain. Vagaries in cobalt distribution in the tungsten carbide substrate makes wear difficult to predict. Nevertheless, compared to non-diamond inserts, a tool-life increase of 10 to 50 times is common--depending, of course, on machining conditions and material.

At this time, diamond tools are limited to cutting only non-ferrous materials. However, experiments involving super-cold gases blown into the interface between a steel workpiece and a diamond tool are being conducted with encouraging results. It may be practical to cut ferrous materials with diamond in the near future.

By Chris Koepfer

Anatomy of a Diamond Coated Insert

2008-01-30T07:36:00.000-08:00

The base material, or substrate, for most thin-film coated-diamond inserts is tungsten carbide (grade C-2). It's basically the same substrate material used for many carbide inserts coated with titanium nitride or titanium carbide.

A carbide insert is made from two main ingredients, carbide and cobalt, which are mixed together in various ratios and sintered. Carbide manufacturers guard their ratios and sintering process details the way chefs protect their recipes.

The carbide used in an insert is granular, although individual grains are very smallmany formulas call for grains in the single-digit micron range. By using different grain sizes specific cutting performance can be selected. For diamond coatings to adhere more firmly to the substrate, a larger grain carbide is usually specified so the surface has some roughness.

Cobalt is the "cement" that bonds the carbide grains. It gives the carbide its cutting characteristics of hardness and toughness.

The mixture of carbide and cobalt is pressed in a mold, giving it the shape of an insert. Chipbreakers and other performance enhancing bumps and valley are formed as part of the molding process. These pressings are then sintered. At high temperature, the cobalt flows around the carbide grains creating a strong and very hard bond.

By Chris Koepfer

Types of End Mills

2008-01-23T03:23:00.000-08:00

Flutes - Spiral cutting edge on the end mill. 2 and 4 flute end mills are the most commonly used.

2-Flute - Allows maximum space for chip ejection. Used for general milling operations.
3-Flute - Excellent for slotting. Used for general milling operations.
4, 5, 6, and 8 Flute - A greater number of flutes reduces chip load and can improve surface finish, if feed rate remains the same.

Ball End - Used to mill die cavities and fillets, round bottom holes and slots.

Carbide End Mills - This tool material combines increased stiffness with the ability to operate at higher SFPM. Carbide tools are best suited for shops operating newer milling machines or machines with minimal spindle wear. Rigidity is critical when using carbide tools. Carbide End Mills may require a premium price over the cobalt end mills, but they can also be run at speeds 2 1/2 faster than HSS end mills. For best results mount in a hydraulic type holder.

Coatings - The use of Titanium coated tools will increase the surface hardness of the tool to near 85 Rc. This will allow for greater tool life at increased cutting speeds & feeds (15 - 25%). Melin offers Titanium Nitride (TiN), Aluminum Titanium Nitride (AlTiN), and Titanium Carbonitride (TiCN).

Cobalt - Type of high speed steel tool which has a 8% cobalt content (M42). This material has excellent abrasion resistance for improved tool life over standard high speed steel (M7).

Corner Radius - Conventional end mill with radius ground on the tips of the flutes to help reduce chipping on the tip. For mold applications, radius tools can remove more material faster than ball ends.

Corner Rounders - Cutters having form ground radius with relieved clearance.

Double End - An end mill that has teeth on both ends of the cutter. End mill holders must have sufficient clearance to allow for the use of a double end cutter.

Drill Point - Multipurpose tool which can be used for drilling, milling, or chamfering.

High Helix - Usually a 40 to 60 degree spiral on the tool's flutes. Effective for rapid chip ejection in milling of aluminum and other materials.

HSS - A baseline tool steel. In the past, a majority of end mills were made from standard High Speed Steel (M7). Usually inexpensive, but do not offer the tool life or speed and feed advantages of Cobalt and Carbide end mills.

Left-Hand Spiral - Used for milling multiple layers of thin sheets where chip flow is directed away from work.

Rougher (Hoggers) - End mill with interrupted shape on outside diameter to remove large amounts of material quickly. Typically can remove material up to three times the rate of conventional end mills with different types available to achieve the desired finish on the material. Melin offers roughers in Coarse Pitch, Fine Pitch, Rougher/Finisher, and 3-Flute for Aluminum styles.

Single End - Teeth on one end of the cutter only. This style is the most common available.

Stub Length - Used for milling of shallow slots in all types of materials where heavy feeds are required and tool deflection is minimized.

Wear of CBN in Hard Turning

2008-01-21T09:13:00.000-08:00

Hard turning is a developing technology that offers many potential benefits compared to grinding, which remains the standard finishing process for critical hardened steel surfaces. To increase the implementation of this technology, questions about the ability of this process to produce surfaces that meet surface finish and integrity requirements must be answered. Additionally, the economics of the process must be justified, which requires a better understanding of tool wear patterns and life predictions. An ongoing comparative study of wear rates and tool lives under varying cutting parameters is presented here. To date, the study has consisted of seventeen different machining conditions with four different cutting tool materials. Tool life results agree with previous research in this area, indicating that polycrystalline cubic boron nitride CBN tools with low CBN content have improved lives resulting from the benefits of the ceramic binders compared to the cobalt binder typically used for higher CBN content tools. More interesting is a resulting trend in flank wear patterns that could currently help to predict tool life under certain cutting conditions. Further work is being done to understand the wear process in an attempt to model this relationship for a larger range of conditions.

Ty G. Dawson and Dr. Thomas R. Kurfess
The George Woodruff School of Mechanical Engineering,
Georgia Institute of Technology,
Atlanta, Georgia, USA 30332-0450

NFL Playoff Football

2008-01-13T18:13:00.000-08:00

Its the start of another playoff season in the NFL and much to my disappointment the Detroit Lions have someone once again found themselves on the outside looking in.

As a long time fan of the inept Liedowns, I found myself drinking the Kool Aid this season. At 6 and 2 I was in the Club at Ford Field screaming playoffs just like everyone else. I mean even if the Lions went .500 the rest of the way they were going to make the playoffs, but 1 and 7? Are you kidding me? However, in my heart I knew this was coming. I mean it isn't as if the Lions have ever given me reason to think they would do anything but rip the hearts out of long time Lions fans everywhere.

It has gotten so bad that we have this flawed logic, that according to Murphy (Law that is) we can't pass on our season tix, because someone else might buy them and that's the year the Lions will make the playoffs. How sick is that logic.

But we may just be a symptom of the no fun league as with profit sharing and the such, it really doesn't matter if we don't show up, or renew our tickets, as the team still makes money. That's right folks in the NFL it doesn't matter if you put a good product on the field, you gets paid 4 sho.

I'm not exactly sure where I am going with this rant except I think by putting in words on 2007's version of paper, I am getting self therapy. So of course I will renew my tix, wait for the draft and be extremely excited for the hope of playoffs when we draft another receiver.

Machining D2 with CBN Inserts

2008-01-11T04:40:00.000-08:00

Interrupted cutting D2 tool steel is very difficult and unpredictable. D2 contains up to 14% Chromium and was designed to be used at 50-56 HRc. If the material is hardened to +60 HRc and not tempered very carefully, Chromium Carbide formation at the grain boundaries makes the material impossible to machine with interrupted cutting.

Using PCD and its APPLICATIONS

2008-01-11T04:23:00.000-08:00

Machining Non Ferrous Metals and Alloys including Metal Matrix Composites.

Machining Plastics, Rubber, Fibre, Reinforced Plastics and CompositeS

Machining Chipboard, MDF and Natural Woods

Wear Pads, Gauging Points and Probes

PCD can offer dramatic improvements in both efficiency and product quality, but the following points should be considered:-

If conventional tools fail prematurely due to breakage, DR-PCD tools are unlikely to fair any better. If excessive vibration, inclusions in component material, or similar problems cannot be avoided, then it may be preferable to continue breaking relatively cheap conventional tools.

However, the benefits offered by DR-PCD tools can often provide the incentive to overcome these problems. DR-PCD tools may give a tool life improvement of 100 times, paying back any extra costs in improving the machinability of the material, improving the work holding or optimizing the cutting tool geometries.

Although DR-PCD is both tough and extremely hard, the cutting edges can be extremely fragile. Care must be taken to avoid chipping the cutting edges.

It should be remembered that diamond and graphite are two forms of the same element, Carbon. When diamond is produced synthetically from graphite, a catalyst is used to reduce the reaction time to a commercially acceptable level. Suitable catalysts are iron, nickel or cobalt.

Unfortunately, these elements also catalyze the transformation of diamond into graphite. Diamond is not therefore generally effective for machining ferrous, cobalt or nickel based materials.

WHAT IS PCD (POLYCRYSTALLINE DIAMOND)

2008-01-11T04:21:00.000-08:00

Diamond is the hardest, most abrasive-resistant, material known to man. These properties make diamond an ideal cutting tool. Within the crystal structure, however, fracture planes, used by the diamond cutter to produce the gem diamond from the rough, can cause catastrophic breakage of the tool edge, when subjected to impact.

DR-PCD tools incorporate Polycrystalline Diamond blanks produced under conditions of high pressure (1 million PSI) and temperature (1700 Degrees C), similar to those of diamond synthesis. Randomly orientated, carefully selected synthetic diamond crystals are grown together on a hard metal substrate. This results in a material with the hardness, abrasive resistance and high thermal conductivity of diamond with the toughness of hard metal.

Using the hard metal substrate the PCD blank is brazed to a carrier, either steel or hard metal, and machined by grinding or E.D.M to produce the cutting edge.

When compared to other cutting tool materials, there are three main reasons for using DR-PCD tools:-

Increased tool life results in reduced tool cost per component and less idle machine time.

Increasing cutting speed improves productivity through reduced cycle times.

Grinding and other less productive machining methods can be replaced by DR-PCD milling and turning.

For more information on PCD Inserts please visit:

David Richards Engineering

Carbide Inserts For Screw Machines

2007-12-28T13:38:00.000-08:00

There have been recent advances in carbide technology that allow these types of tools to run at the lower cutting speeds often encountered in screw machines. Also, there has been a greater willingness by the major carbide manufacturers to produce designs for this segment of the market. The benefits to the industry can be looked at from several different points. The most important are as follows.

Increased cutting speeds and higher production rates
Decreased down time
Higher quality
Lower overall tool costs
Operator safety

As in any manufacturing environment, the quantifiable advantages have to outweigh the cost and time to justify considering a switch to different tooling. This is probably even more important within the screw machine industry.

The types of cutting tools in use today have been used for years. Operators, setup personnel and designers are familiar with them and feel comfortable using them. In addition, many people in the screw machine industry have a "bad taste in their mouth" when it comes to indexable, throw-away carbide inserts. When these inserts first began to become popular in other aspects of machining in the mid-1960s, people in the screw machine industry unsuccessfully tried them. At that time, the carbide grades and pressing technology did not exist to meet their requirements. A careful examination of the potential benefits will show significant improvements.

Thanks to www.productionmachining.com for the tip 2001

Turning and Boring Troubleshooting

2007-12-17T14:31:00.000-08:00

Difficulty

Common Cause

Melted Surface

1.	Tool dull or heel rubbing
2.	Insufficient side clearance
3.	Feed rate too slow
4.	Spindle speed too fast

Rough Finish

1.	Feed too heavy
2.	Incorrect clearance angles
3.	Sharp point on tool (slight nose radius required)
4.	Tool not mounted on center

Burrs at Edge of Cut

1.	No chamfer provided at sharp corners
2.	Dull tool
3.	Insufficient side clearance
4.	Lead angle not provided on tool (tool should ease out of cut gradually, not suddenly)

Cracking or Chipping of Corners

1.	Too much positive rake on tool
2.	Tool not eased into cut (tool suddenly hits work)
3.	Dull tool
4.	Tool mounted below center
5.	Sharp point on tool (slight nose radius required)

Chatter

1.	Too much nose radius on tool
2.	Tool not mounted solidly
3.	Material not supported properly
4.	Width of cut too wide (use 2 cuts)

Drilling Tips

2007-12-17T14:19:00.000-08:00

Drilling Tips

Smaller diameter holes

High speed twist drills
Peck drill suggested

Larger diameter holes

Drill pilot hole
Use slow speed spiral drills or inserted drills

Taps - Dealing with Poor Thread Quality

2007-12-14T04:55:00.000-08:00

Video - Introduction to Threading Basics

Machine Set up for Hard Turning

2007-12-13T07:51:00.000-08:00

The key is to maximize rigidity. You should attempt to achieve the smallest possible tool overhang, and spindle rotation should put cutting forces into the machine bed. Stop cutting if chatter occurs. Coolant (spray mist or flood) is appropriate for continuous cutting--you can achieve up to a 20% increase in tool life with high-pressure coolants. Spray mist is often used in Europe, due to the high cost of disposal (since less coolant is used in all applications), and dry machining is being investigated aggressively in Europe. For intermittent cutting, do not use coolant. Dry cutting may benefit from the application of compressed refrigerated air.

MILLING; ROUGHING END MILLS, COARSE OR FINE PITCH

2007-12-13T05:19:00.001-08:00

When should you use a coarse pitch, and when should you use a fine pitch?

Roughing end mills with sinusoidal waveform are designed to reduce side pressure and cut the chips into much smaller segments.

This reduces chatter, vibration, and deflection, allowing much higher material removal rates without increasing horsepower requirements.

Coarse pitch profiles are recommended for deep slotting and heavy side cuts in medium strength materials where heavy metal removal rates are required.

Fine pitch profiles provide a stronger edge, better tool life, and better surface finish.

These work well for shallower cuts in harder steels, and high temperature materials like inconel and hastalloy.

Advantages of Diamond Coated Inserts

2007-12-11T04:58:00.002-08:00

Accuracy: The diamond coating is very thin, but very hard, and tools don’t change significantly in size during their life. For instance, the radius on an endmill will change by about 10 microns (0.0004") from when new to the point that it is worn out.

Speed: Diamond tools can typically be run at two to three times the surface speed of carbide tools.

Dry cutting: Diamond tools can often convert an operation from wet to dry machining, providing a significant saving in overall machining costs.

Machining Ferrous Materials with Diamond

2007-12-11T04:56:00.001-08:00

Why can't you machine ferrous metals with diamond?

Diamond is unaffected by almost every other chemical or compound in nature. One exception is hot iron. The carbon atoms in diamond will dissolve into the iron, quickly eroding the diamond surface. Iron wheels are used for polishing natural diamond.

TaeguTec Insert Grades

2007-12-10T10:16:00.000-08:00

Announcement

www.pgstools.com has just added a TaeguTec Insert Grades Chart. This insert grade chart lists speeds and feeds for TaeguTec Inserts as well as a list of TaeguTec Insert Grades.

Machining Green Ceramic

2007-12-07T04:25:00.000-08:00

CVD diamond tools provide a wear life gain of 25x to 100x

over uncoated carbide when machining green ceramic

The abrasive nature of green ceramic severely limits the life of carbide tools, necessitating frequent tool changes. The extended wear life of diamond tools, on the other hand, permits many machining operations to be performed with minimal or no supervision. The very gradual wear of a diamond tool also makes it much easier to maintain workpiece accuracy, thereby minimizing any need for slow and expensive machining after firing. Another advantage of diamond tools is faster machining — speeds can be increased 10 to 20%, and feeds up to 100%.

Machining Waspaloy

2007-12-07T04:06:00.001-08:00

First of all What is Waspaloy?
Waspaloy is a precipitation hardening, nickel-based alloy which has been used in elevated temperature applications. The alloy has been used for gas turbine engine parts which require considerable strength and corrosion resistance at temperatures up to 1600°F (871°C). Waspaloy is usually vacuum-induction plus consumable electrode remelted.

Waspaloy Corrosion Resistance?
Waspaloy has excellent resistance to corrosion by combustion products, encountered in gas turbines and aircraft jet engines, at temperatures up to 1600°F. Intergranular oxidation occurs at temperatures above 1600°F.

Waspaloy Machinability
Waspaloy is difficult to machine in any condition of heat treatment. The air-cooled, solution treated condition is best for most operations (this is Rockwell C 30 partially aged). Rigid, well-powered machines are required for best results. Cemented cardide tools are preferred for most operations and care must be exercised to obtain positive cuts at all times, otherwise "glazing over" and work hardening of the surface will occur.
The following tool geometry, feeds, and speeds have been found satisfactory for lathe turining:
0° back rake
6-8° side rake
5-8° clearance (end and side)
15-20° lead angles may be used to reduce feed pressure on roughing cuts.
Speeds of 35/50 sfm will feeds of 0.005/0.15" per revolution are recommended. Slower speeeds and greater feeds should be used for roughing cuts and faster speeds and lighter feeds for finishing cuts. Better tool life will be obtained by machining in the solution treated condition; however, a smoother finish can be obtained by machining in the fully aged condition.

Carbide Inserts Versus HSS

2007-12-06T12:26:00.000-08:00

One of the main benefits of using carbide inserts versus high speed steel (HSS) is that carbide is able to withstand much higher temperatures. Some times carbide will allow the machine operator to permit faster speeds increasing productivity. Addtionally carbide inserts may leave a better finish when tested against HSS. Carbide is typically considered to be more brittle than other materials. This can result in more frequent chipping or breaking. To compensate for this most manufacturers make tools that allow for inserts that fit within an insert holder. This allows for easy replacement of the carbide inserts at low costs since the entire tool does not need to be replaced. Today the majority of mills, end mills and lathe tools utilize carbide inserts.

IPM (Inches Per Minute) Calculator

2007-12-03T08:45:00.000-08:00

pgstools.com now offers an online calculator for IPM (Inches per Minute).

Beta Blog

2007-11-26T15:16:00.001-08:00

We would love to have feedback on a new style we are trying out for our blog. We think this layout is more user friendly.

Of course we will never know without your feedback. Check us out at:

http://carbideinserts.blogspot.com/

Carbide Insert For Cutting Aluminium

2007-11-24T08:11:00.001-08:00

Here are a couple of pretty cool insert for cutting aluminum, you can click on the picture for more detail. We have found that this insert performs quite well for aluminum machining. There are two choices available for chipbreakers. In the first picture is the "TA" and the "HA" is in the second picture. Each one serves a different purpose, so read carefully. Both inserts are from Korloy. For pricing on inserts for cutting aluminum: RCGT0602MO-AK H01

CBN Boring Tools - Brazed, Bar(s), Tipped, and Inserts

2007-11-24T07:47:00.000-08:00

A question I get asked quite often, is what sort of tool would be best for hard boring my x,y or z. Well that all depends on the answers I get for these questions:

What is the min. bore diameter?

What is the bore depth?

Are you willing to use a different tool?

Instead of sending me answers to these questions, here is a quick guide for boring applications:

Size of Bore = Recommended Tool

8mm or smaller= CBN Tipped Brazed Boring Tools

8mm – 10 mm= CCMW 06 or CCMW 2(1.5) CBN Insert

10mm – 16 mm= CCMW 09 or CCMW 3(2.5) CBN Insert

25mm – up= CNMA CBN Insert

Machining Titanium - Roughing, Finishing, Milling, Turning

2007-11-19T19:57:00.000-08:00

High speed machining titanium

Titanium alloys are particularly difficult to machine due to the high degree of reactivity between the cutting tool and the hot metal chips which flow across it. Chipping and breakage of the cutting edge are significant problems in this application. One of the best tool materials to use to machine titanium is an uncoated cemented carbide grade of material. However, because it is uncoated, its application range is limited to low speeds. Some improvements have been achieved by coating this substrate with a PVD TiN coating.

CBN Grade Cross Reference Comparison

2007-11-16T09:31:00.000-08:00

CBN Grade Cross Reference Comparison

If you are looking for a place to compare CBN grades from Sandvik, Sumitomo, Iscar, Dijet, Kennametal, Mitsubishi, Tungaloy, and Kyocera, then you have come to the right place. This chart covers CBN Inserts and PCD Inserts.

Generally speaking, a search on the web will net you quite a few results, however rather than click on all those links how 'bout just one?

Give this a shot: CBN Insert Grade Comparison

Inserts for Machining Inconel

2007-11-15T14:37:00.001-08:00

Korloy offers Solution for Super alloy & Heat Resistant Ti-alloy TURNING!

PC8010 New PVD Coating

Features of PC8010

- PVD coated S10 grade
- Heat Resistant Super Alloy (HRSA) turning grade
- Good wear resistance and anti-adhesion of new coatinglayer
- Offers Prolonged tool life

Wear Resistance of PC8010 (click picture to enlarge)

Application Examples of PC8010 (click picture to enlarge)

Speeds and Feeds for PC8010 (click picture to enlarge)

Speeds and feeds for machining:

Ni-based alloy(Inconel, Hastelloy)
Fe-based alloy(MA-956, Incoloy909)
Co-based alloy(Stellite, Haynes25)
Ti-alloy(Ti-6Al-4V..)
SEE PICTURE ABOVE

Find PC8010 Inserts @ www.pgstools.com enter PC8010 in the search box for all insert styles available

Machining Ceramic with PCD Inserts

2007-11-15T08:03:00.000-08:00

The light weight of ceramic materials and their outstanding resistance to wear and high
temperatures make them increasingly preferred for industrial applications. However, machining
ceramics is very costly and time consuming.

Grinding, with its high cost and low volume material removal rate (MRR), is still the most common method used to finish machine sintered (fired) ceramic components.

New machining methods must be evaluated in order to produce ceramic components in a more timely, cost-effective manner.

Therefore to minimize the time and cost associated with finish machining after sintering, ceramic materials should be machined in the bisque state with PCD tooling whenever possible.

Expected Benefits
- Reduced operation time by 90% by rough machining in bisque state, when compared to grinding
- Reduced labor costs
- Increased competitiveness of ceramic components

David Richards Engineering specializes in the manufacture of PCD Inserts and cutting tools. They offer extensive experience in the machining of carbide with PCD tools. Contact them via sales@drengus.com for information regarding speeds and feeds and recommended tooling.

Drilling

2007-11-14T05:12:00.000-08:00

Machinists have the choice of four basic types of drills that are made with carbide cutting edges: solid carbide drills, drills with indexable-inserts, drills with brazed carbide tips and drills with exchangeable solid-carbide tips. Each of these drills has advantages for specific applications.

Solid-carbide drills are made to be used on modern machining centers. These drills are manufactured with fine-grain carbide and titanium aluminum nitride (TiAlN) coatings to provide long tool life. As self-centering drills, they have a specially designed edges that help to control chips and chip evacuation in most workpiece materials. The self-centering geometry and fine tolerances of solid-carbide drills ensure quality holes without additional machining.

Indexable-insert drills cover a broad range of diameters with depths two times diameter to five times diameter. They may be used for rotating applications as well as in lathes.

Drills with brazed carbide tips rely on the strong connection of the brazed tips to the drill bodies. These tools use a self-centering geometry for low cutting forces and good chip control in most workpiece materials. Brazed drills produce holes with relatively high surface finish, close diameter tolerances and good positioning accuracy without additional finishing operations. These drills are available with through-the-tool coolant, and can be used in machining centers, CNC lathes or other machines that have sufficient stability and rpm.

Drills that have exchangeable solid-carbide tips incorporate a steel body with the exchangeable tips that are known as crowns. These tools offer the precision of brazed drills, and offer increased productivity at reduced operating costs. The carbide crowns used with this new generation of drilling tools are available in precise size increments and have a self-centering geometry to produce close diameter tolerances.

Drilling tolerances and machine stability

REF: www.cutting-tool.americanmachinist.com

Ceramics and CBN Inserts

2007-11-13T13:21:00.000-08:00

For high-speed, dry, and hard machining, these cutting tools may prove the ideal solution

Ceramics' and cubic boron nitrides' (CBN) hardness, chemical stability, and high wear-resistance make the materials, even at elevated temperatures, well-suited for high-speed and hard machining that can achieve significant reductions in production time and cost. The ability of ceramic inserts and CBN inserts to run dry also allows cleaner machining processes with reduced environmental and health impact-saving coolant, maintenance, and disposal costs. In the high-performance cutting of cast iron, nodular or ductile cast iron, and in the turning of hardened steel, the materials enable productivity gains and cost efficiencies, which have resulted in recent market share gains by both ceramic and CBN cutting tools within the automotive industry.

Carbide Insert Grade Comparison Chart

2007-11-12T15:13:00.001-08:00

www.pgstools.com has just listed a carbide insert grade comparison chart to help compare the different grades across the following manufacturers:

Kennametal, Sandvik, Carboloy Seco, Korloy, Sumitomo, Kyocera, Iscar, Toshiba Tungaloy, Mitsubishi, Valenite, and Taegutec.

Find the chart here:

carbide insert grade comparison chart

Machining Bimetals

2007-11-12T05:52:00.000-08:00

Bimetal components put hard materials in select wear areas surrounded by or mixed with softer alloys. They are gaining popularity in the automotive industry and elsewhere, and they pose special machining challenges. The CBN inserts that are so productive cutting alloys with greater than 50 Rc hardness can fracture if they hit softer materials. PCD inserts able to machine abrasive aluminum suffer excessive wear cutting ferrous metals.

Machining bimetals productively calls for refined machining routines developed by the user, tool supplier and machine vendor. In one application, the hard powder metal composite alloy described earlier was hot isostatically pressed onto a less costly 316 stainless steel substrate. A helically interpolated tool path programmed into the machine control applied optimum feeds and speeds to machine the powder metal zone first, then the backing.

To machine bimetal cylinder blocks productively, automakers must contend with both abrasive aluminum alloys and cast iron cylinder liners. The design of the part means hard iron wear zones cannot be isolated from the soft aluminum. However, machine programs providing very low speeds and very light depths of cut enable abrasion-resistant PCD inserts to machine both aluminum and iron without frequent tool changes.

CBN Machining Applications – Where is CBN Machining Cost Effective?

2007-11-12T05:41:00.000-08:00

CBN Machining Applications – Where is CBN Machining Cost Effective?

“Hard Turning” Tool Steels 45Rc to 65Rc+

Speeds of 200 SFM to 600+ SFM (Surface Feet per Minute)
Chip loads of .002 to .020 IPR (Inch per Revolution)
Depth of cuts .002 tp .200"
Finishes to 16-Ra+
Interrupted cuts – NO Problem
Solid-top CBN inserts eliminate the problem of Mini-tip Melt-Off

Chilled Cast Irons (as cast) & Grey Cast Irons

* 300% Increased productivity vs. carbide
* Wear life 5 to 10 times TiN coated carbide
* 200% wear life in finishing cuts vs. ceramics
* Speeds start at 1600 SFM to 1400+
* Chip loads .004 to .020 IPR
* Depth of cut .002" to .400"
* Operations include turning, milling and boring

NiHard (White Iron) 450 Bhn to 750Bhn

* Speeds range from 250 SFM to 400+ SFM
* Roughing chip loads -.005" to .015" IPR
* Roughing depth cuts -.010" to .400"
* Finishing cuts, chip load starts at .002 to .020" IPR
* Finish cuts, depth of cuts -.002 to .300"
* Operations include turning, milling and boring
* Acme threading both ID & OD

Machining Sofware Now Available at pgstools.com

2007-11-09T09:42:00.001-08:00

pgstools.com is now offering the Machinists Calculator for sale on its website. You can find the software here:

Machinist's Calculator

The Machinist’s Calculator software has been developed to quickly solve common machine shop trigonometry and math problems at a price every machinist can afford!

All calculations switch between inch and metric

Right angle and oblique trigonometry

Speeds and feeds, RPM to surface speed, etc.

Drill point and countersink depth

Drill size conversion charts

Tapping drill charts

Chord data calculations

Dovetail calculations

Bolt circles and grid layouts

Measuring threads with wire calculations

Hexagon and other regular polygon calculations

Ballnose cutter/surface finish calculations

Carbide Insert Directory Now on Squidoo

2007-11-09T05:47:00.000-08:00

An attempt at a one stop location for information, technical and otherwise, on carbide inserts, cutting tools and machining. Find links to speeds and feeds, carbide insert grade charts, cross reference, and more.

Check us out:

http://www.squidoo.com/carbideinsert/

Hard whirling

2007-11-09T04:56:00.000-08:00

Whirling & CBN Simplify Hard Part Operations

Hard part machining is the manufacturing process that many industries are turning to. The Aerospace segment uses CBN cutting tools to make landing gear struts, also Automotive manufacturers use it for steering worms and worm gears, the Medical field for implants and the Machine Tool industry for ball screw manufacturing. All rely on Cubic Boron Nitride (CBN) inserts to machine hardened material.

Today’s CBN grades are far more versatile than they were a few years ago. Manufacturers used to avoid using CBN even on mildly interrupted parts because of its fragile nature, but now CBN grades can cut through even severely interrupted parts without a problem.

Using a Cubic Boron Nitride cutting tool material, steels as hard as 65 HRc can be machined. CBN has a uniform high hardness and excellent abrasion resistance in all directions. Edge retention permits more effective cutting with less tool wear, which helps maintain part geometry of greater precision and consistency.

An innovative break-through has been the introduction of CBN cutting tools into the whirling process. The combination of today’s latest CBN material with the smooth tangential cutting action of whirling results in a revolutionary process for cutting threads in hard materials.

Hard whirling is done dry, without coolant. The chips carry away nearly all of the heat during cutting, leaving the workpiece cool and minimizing any thermal geometry variations. The surface finish and profile accuracy are close to grinding quality.

Many ball screw manufacturers are discovering that hard whirling can eliminate a number of previous mandatory operations in their process. For example, a ball screw would be rough- machined in the soft state, case hardened, straightened and then finish ground.

Milling with PCD from David Richards Engineering

2007-11-08T07:46:00.000-08:00

Milling with PCD from David Richards Engineering

Fixed Pocket Cutters and Precision PCD Inserts

PCD (Polycrystalline Diamond) has been available for miling non-ferrous abrasive materials for many years. The common method of tool production has been grinding using Diamond Grinding Wheels. the forces required to grind PCD with Diamond are extremely high. this means that it has been very difficult to product cutting tool inserts accurately enough to work properly in the fixed pocket milling cutters commonly available.

Cutters with adjustable pockets for the inserts were developed, but these require care and patience to set up and are expensive to buy and repair.

Using the latest wire erosion technology David Richards Engineering have developed techniques which produce PCD tipped cutting tool inserts that are as accurate as Precision Ground Carbide.
Installed in the best quality Diamite cutter bodies, Diamite PCD Inserts provide all the Tool Life and quality advantages of PCD with the convenience of Carbide.

Tools available:

Face Milling Cutters
End Milling Cutters
APKT PCD Inserts

For more information please contact:

David Richards Engineering Limited by drengineering@aol.com or www.dreng.co.uk

Korloy Introduces New 3120 Grade

2007-11-08T07:32:00.000-08:00

Korloy has introduced a new coating for their carbide inserts called NC3120.

Some special features of NC3120:

-Toughness of the coating has been increased due to the special treatment

- New Al2O3 film has excellent hardness

- Due to the special intermediate film layer that has been employed, there is excellent bonding achieved

-Columnar MT-CVD film for mechanical wear & shock resistance

- Due to the combination of a new coating layers & special treatment, excellent toughness & anti built-up edge properties achieved

- Consistent performance under a variety of cutting conditions achieved

Speeds and Feeds:

Application Examples:

One of the best carbide turning inserts for steel

Material Work Hardening in Machining

2007-11-08T04:43:00.000-08:00

Work hardening of materials is a condition to be avoided. What causes work hardening is the heat generated by the cutting tool transferring to the work piece material causing plastic deformation. In fact, it is appears to act like a heat treatment to the work piece but on a lower scale. To recognize this condition the part being machined will have a very shiny glazed surface and appear slippery. The hardness in the machined part can even realize the same hardness of the cutting tool.

Steps to take to overcome this condition:

1. Make sure the cutting tools are always sharp!

2. Run at the recommended feeds and speeds for the material being machined. If incorrect, rubbing vs. cutting will increase heat.

3. Use coolant-feeding tools. Water based coolant should be used at about 8% to 10% mix.

4. Do not dwell tool in one position.

5. When drilling, run with constant feed if possible.

6. If peck drilling, reduce number of pecks and withdraw each one tool diameter.

When experiencing tap breakage, the cause may not be the tap, but a work hardened hole.

Materials likely to work harden are stainless steels and high temperature alloys.

Once again, proper tool maintenance will help to reduce work hardening problems.

Whiskered Ceramic Inserts

2007-11-06T10:45:00.000-08:00

Reinforced or whiskered, ceramics use extremely fine-grained silicon-carbide crystals that are called “whiskers” because they resemble small hairs under a microscope to reinforce and toughen basic ceramic compounds.

In ceramic tool materials, single-crystal silicon carbide whiskers, on the order of one micron in diameter and 0.003937 in. (100 microns) in length, are intertwined within the alumina-matrix structure. These whiskers have a tensile strength of about 1 million psi and dramatically improve the fracture toughness of the tool material. They also effectively block and prevent propagation of cracks.

Reinforced ceramics work differently from other cutting materials. With reinforced ceramic cutting tools, the objective in machining is to generate high temperatures ahead of the cutting tool to soften or plasticize the workpiece material. That facilitates the removal of material and a reduction in cutting forces. The ideal cutting temperature in nickel alloy is about 1,800 degrees F, for example.

Cutting with ceramic inserts requires high surface speed and balanced feedrates. High speed is necessary to generate the high temperature in the shear zone and to ensure that the heat propagates into the chip-forming zone immediately ahead of the cutter. When cutting speeds are too slow, insufficient heat is generated to soften the material in this zone, and the cutting forces are raised and insert failure occurs.

A strategy for using ceramic inserts is to program fewer, but deeper cuts that bury the insert deep in the workpiece. This moves the notch formation further up the face of the insert to an area that has a larger, stronger cross section. Ramping cuts should be programmed to accommodate these tools and fixed depths of cut should be avoided to spread wear over a larger section of the insert.

When machining interrupted cuts with reinforced ceramics, it is important to keep the speed of the cutter high. A rule of thumb is to estimate the percentage of voids in the workpiece surface and increase cutting speed by that percentage. This increase in surface speed offsets the loss of heat generation created by the voids.

Whiskered ceramics work best on hard ferrous materials and difficult-to-machine nickel-base alloys, including Inconel, Waspoloy and Hastelloy. They do not work well on ferrous alloys below Rc 42 hardness because of the chemical reaction that occurs between iron and the carbon that is part of the silicon carbide reinforcing material.

REF: http://www.cutting-tool.americanmachinist.com/BDEList.aspx

Machining Plastic

2007-11-06T10:02:00.000-08:00

When machining plastic, remember...

Thermal expansion is up to 10 times greater with plastics than metals
Plastics lose heat more slowly than metals, so avoid localized overheating
Softening (and melting) temperatures of plastics are much lower than metals
Plastics are much more elastic than metals

Because of these differences, you may wish to experiment with fixtures, tool materials, angles,speeds and feed rates to obtain optimum results.

Getting Started

Positive tool geometries with ground peripheries are recommended
Carbide tooling with ground top surfaces is suggested for optimum tool life and surface finish. Polycrystalline diamond tooling provides optimum surface finish when machining
Use adequate chip clearance to prevent clogging
Adequately support the material to restrict deflection away from the cutting tool

Solutions For Hard Milling

2007-11-06T09:54:00.001-08:00

Makino demonstrates the latest techniques and technologies for high-speed machining of hardened materials for die or mold applications. Check out tips, tricks, and new technologies you can use to mill the toughest steels, shortening your lead times, lowering your costs, and eliminating bench work.

Click here to launch This presentation.

Advantages of Diamond Coated Inserts

2007-11-06T09:48:00.000-08:00

The metalcutting advantages of diamond are well known. It's not only the hardest substance on earth, but it also has a very low coefficient of friction (less than Teflon) and exhibits thermal conductivity several times better than copper.

Until the CVD diamond process became practical, shops had one type of diamond tool available: polycrystalline diamond (PCD). PCD has been used in metalworking for several years. It consists of diamond crystals in a cobalt binder. Segments of the PCD are brazed on the cutting edge of a carbide insert. Usually only one cutting edge receives a diamond segment, which is precisely shaped by a wire electrical discharge machine to fit a recess in the insert.

The cutting edge geometries of PCD are limited, leading the industry to explore CVD thin-film technology as a complement or even replacement.

Flexibility in insert design is a big advantage of thin-film diamond-coated inserts. As with other coated inserts, chipbreakers and rake geometries are molded into the insert when it is pressed. PCD tools, on the other hand, are limited to very basic geometries with few chipbreaker designs available.

The CVD process "grows" diamond over the entire substrate surface. Depth of cut is not limited by the size of the diamond segment as in PCD tools. Complete surface coverage with CVD thin-film diamond also helps chip flow. Because diamond has a low coefficient of friction, chips move across the various faces of the insert smoothly. When cutting gummy materials, this slippery coating discourages material build up on the cutting edge and insert body.

A diamond insert has multiple cutting edges. Because all edges are coated, the inserts are truly indexable--a triangle has three usable edges, a square has four, and so on.

Performance characteristics of CVD diamond inserts are comparable to PCD. In many applications, CVD diamond inserts can be a direct replacement for PCD. In some cases, the use of chipbreaker geometry allows the machine tool feeds, speeds and depth of cut to be increased over PCD tools without such geometry.

CVD diamond inserts tend to wear evenly. As cutting erodes the diamond film to the point where carbide is exposed, the substrate tends to continue cutting although much less efficiently. This gradual wear-through permits in-process tool monitoring when machines are running lightly tended.

REF: Diamond-Coated Carbide Inserts-Ready, Set, Go By Chris Koepfer

WHAT IS POLYCRYSTALLINE CUBIC BORON NITRIDE (CBN)?

2007-11-06T03:15:00.000-08:00

WHAT IS POLYCRYSTALLINE CUBIC BORON NITRIDE (CBN)?

Diamond, cubic carbon, is the hardest, most abrasive resistant material known to man. It is therefore an ideal tool material. Unfortunately, in the presence of heat and iron, nickel or cobalt, diamond transforms to hexagonal form, graphite. This is why ferrous materials are not generally machined with diamond. The second hardest material, Cubic Boron Nitride (CBN), is created by man, using temperatures and pressures similar to those for diamond synthesis, but does not have this inherrant weakness when it comes to the machining of ferrous materials. Used in the correct manner CBN inserts offer cost-effective rapid stock removal and finishing of hardened steels and certain softer ferrous materials.

For more information on CBN Inserts please visit:

David Richards Engineering

Top 20 Tooling Tips For Machining

2007-11-05T05:22:00.000-08:00

Gathered from machine shop and application experts' cutting-tool philosophies and trade tricks, here are 20 productivity tips, application insights and general knowledge on how to get an edge in performance and service life.

Machine tool consumption in the United States totaled $3,080.61 million in 2005, up 8.4 percent from the year prior. As machining and tooling obviously still is a key factor in manufacturing, let’s take a look at some general insights and productivity tips regarding cutting-tool philosophy, here via Modern Machine Shop and Modern Application News:

1. The Costs that Count Focus on cost per part, not the cost of cutting tools, as a key target. Because cutting tools account for only three percent of total production costs in metalworking, upgrading cutting tools is likely to yield more overall cost savings.

2. Cutting Tools are a System Keep both hardware (e.g., cutter bodies and toolholders) and software (e.g., indexable inserts) up to date. When looking at an upgrade in insert technology, consider upgrades in toolholders and cutter bodies, and vice versa.

3. Target and Elucidate When engineering a new process or troubleshooting an existing one, target four main areas and set clear, measurable goals for each: cycle time, tool life, part quality and surface finish. Then rank by priority. Share those goals and priorities with your vendors for better answers sooner.

4. Troubleshooting: Process Problem or Tooling Problem? Don’t be too quick to blame the tool. Instead, use the mode of tool failure as a clue to the root problem. Look at machine rigidity, feed, speed, depth of cut, presentation angle, chip clearance and coolant. If it is a tooling problem, changing the tool will fix it. If the problem is a process problem, it probably won’t matter what tool you use.

5. Coatings Aren’t Only for Inserts Coat cutter bodies to get some important benefits that high-tech coatings bring to carbide inserts: hard coatings on cutter bodies resist wear from contact with hot chips moving at high speeds; chips flow more readily through flutes because the coating gives the surface lubricity.

6. Multifunction Tools for Multitasking Machines Added spindles, tool turrets and rotational axes mean tight clearances and a limited number of tool stations, so consider the possibility of having one toolholder with several multipurpose inserts that can do facing, OD turning, drilling, counter drilling and internal threading without a tool change.

7. Modular Thinking is Lean Thinking To keep tool inventory at a more manageable level, consider modular tooling shanks that accept a variety of interchangeable solid carbide heads. As the heads can be replaced or exchanged while the tool is clamped in the machine, setup time can be reduced.

8. Don’t Neglect Power Consumption Besides energy savings, cutting tools that require less power from the machine tool tend to last longer, cause less wear and tear on spindles and ways, and minimize vibration. A 10 percent reduction in cutting forces is likely to result in a 50 percent improvement in tool life.

9. Get Clamping Forces Right When tightening the clamping screws after indexing an insert, DO NOT GUESS about the torque applied. Under-tightening may allow the insert to chatter or prevent the process from holding tolerances, while over-tightening may break the insert or the key. For a simple way to eliminate uncertainty, consider a torque wrench that automatically lights up to signal that proper tightening levels have been reached.

10. Can Your CAM Software Keep Up? When programming for CNC operations, it is important for toolpaths to match the capability of the cutting tools. Not all CAM software allows the programmer to program the moves that optimize the performance of advanced cutting tools.
11. Think Process FirstSometimes taking an unconventional approach is the answer. Especially on larger holes in one-off or short-run work, milling a hole from solid with helical milling often makes more sense than drilling it. Large-diameter drills may be faster, but they’re a lot more expensive and not near as versatile.

12. Understand Cutting-Metal Forces, Use Them to Advantage Cut in a direction that improves rigidity of the setup. Consider reducing the depth of cut to convert radial forces into axial forces. Then increase the feed rate to take advantage of higher axial rigidity. 13. Take Advantage of Tool Geometry This can improve throughput. For instance, on lead-angle cutters, increase the feed rate to achieve maximum recommended chip thickness.

14. Match Tool Geometry to Material Being Cut Especially in job shops handling a variety of workpiece materials, beware of “general purpose” tooling. Take the time to change tools when you change materials. You’ll get more throughput and make more money that way. Again, the price tag on the tooling is the least important part of the process-economics equation.

15. No Vibes Are Good Vibes Minimizing or eliminating vibration is usually a matter of controlling cutting forces so that they are directed to the most stable, most rigid element of the machining system. Upon every proposed change in tooling, examine how vibration is managed. That is the key to prolonging tool life, protecting the spindle and improving surface finish.
16. The True Meaning of “Indexable”To make sure you are getting the full value of the original concept of carbide inserts with indexable edges, look for styles that offer the most in multiple edges and be sure the edges truly are usable.

17. Combining Process and Cutting Your Time in Cut Combining several processes into one makes can increase efficiency and reduce costs. The time required for the separate machining cycles, as well as the time required for tool changes, can be reduced or eliminated. Further, tooling costs can be reduced by reducing the number of tools required for a job. (See also Tip 6.)

18. Understand Heat Know where heat comes from and how it can help or hurt you.
Metalcutting will always generate heat, not all of it from friction. In steel machining in particular, you want only enough heat to soften the workpiece material and form good chips. Avoid heating levels that can trigger hardening reactions in the material, overheat the tool or decarburize (crater) the insert.

19. Maximize Your Liquid Assets For coolant-fed drills, there are two parts to the battle: getting the coolant to the cutting edges and getting the chips out of the hole effectively. Thus, coolant flow and chip flow must be considered equally.

20. Return to School Companies sending their engineers and programmers back to classes often see a fresh return on their investment each time, a return that comes usually within weeks of completing the class. Their people come back excited to apply their new knowledge right away. Some of the excitement may rub off on co-workers. If you’ve tooled a job the same way for more than three years, odds are there’s a better way that will make you more competitive.

Sources
Upgrade Your Cutting Tool Mindsetby Mark Albert Modern Machine Shop, July 2005
Teacher’s Top 10 Tooling Tipsby Dave Eisele Modern Application News, July 2004
Additional
Get an edge on tool performanceby James Benes American Machinist, December 2005

What is the definition of indexable carbide insert drill?

2007-11-02T05:15:00.002-07:00

A drill with carbide inserts clamped to a steel body. Indexable carbide drills are among the most cost-effective drills.

What is the definition of carbide insert?

2007-11-02T05:15:00.001-07:00

A cutting bit made of hard carbide material that has multiple cutting edges. Once a cutting edge is excessively worn, it can be indexed to another edge, or the insert can be replaced.

Payoffs And Tradeoffs of CBN Inserts

2007-11-02T04:45:00.000-07:00

CBN inserts incorporating reinforced, chamfered edges eliminate the edge breakout common when cutting materials harder than 50 RC.

Consider the entire application. Less expensive carbide inserts that can do the job in terms of tolerance and surface finish may be costly when the time spent indexing and replacing inserts is considered. Real productivity results from an understanding of the tradeoffs in throughput, cycle time and insert performance.

In one specialized, low-volume example, a sintered titanium carbide gas turbine blade was milled successfully with coated carbide cutting inserts. At 120 sfm, the carbide cutting edge cut well for just 5 to 10 minutes. Acceptable insert life is typically placed at 15 to 30 minutes in high volume production with difficult materials, but with a low-rate part, the short insert life and frequent tool changes are not major drawbacks. Longer insert life does become important in full production, however, to decrease tool-changing downtime and labor and to increase machine utilization and throughput. Carbide works well for the turbine blade for now, but should the part go to higher volume production, the application may justify harder, more costly inserts made of CBN.

Productivity with advanced material inserts requires adopting the right feeds and speeds. CBN inserts incorporate reinforced, chamfered edges to eliminate the edge breakout common when cutting materials harder than 50 RC. Yet even despite this toughness, CBN inserts demand cutting machine parameters held to tight tolerances. Cutting speeds 10 percent too low or 10 percent too high can dramatically hamper performance.

If faced with the need to machine a difficult material, consider contacting your cutting tool supplier. Suppliers can offer solutions based on how others have approached the same problem. When experimentation is required, careful trial-and-error generally starts with carbide inserts and moves on to harder and more costly cutters. Modern insert geometries, rigid toolholders and refined machining routines often make less costly carbide inserts suitable for tough jobs.

Replace Grinding with CBN Inserts and Hard Turning

2007-10-31T08:13:00.000-07:00

You can replace grinding with CBN Inserts and Hard Turning with a little bit of research. In the vast majority of cases hard turning with PCBN can replace a grinding operation. Finish turning of hardened components can achieve similar tolerances and surface finishes. Hard turning with PCBN also offers several environmental and cost benefits over grinding. These include greater process flexibility, reduced machine time, lower energy consumption, optional use of coolant and swarf recycling possibilities.

What is Hard Turning?

2007-10-31T08:09:00.000-07:00

What is hard turning?

Hard turning is defined as the process of single point cutting of part pieces that have hardness values over 45 Rc. Typically, however, hard turned part pieces will be found to lie within the range of 58-68 Rc. The hard turning process is similar enough to conventional “soft” turning that the introduction of this process into the normal factory environment can happen with relatively small operational changes when the proper elements have been addressed.

Hard turning is best accomplished with cutting inserts made from either CBN (Cubic Boron Nitride), Cermet or Ceramic. Since hard turning is single point cutting, a significant benefit of this process is the capability to produce contours and to generate complex forms with the inherent motion capability of modern machine tools. High quality hard turning applications do require a properly configured machine tool and the appropriate tooling. For many applications, CBN tooling will be the most dominant choice. However, Ceramic and Cermet also have roles with this process.

The range of applications for hard turning can vary widely, where at one end of the process spectrum hard turning serves as a grinding replacement process, and can also be quite effective for pre-grind preparation processes. The attractiveness of the process lies in the performance numbers. A properly configured hard turning cell would typically demonstrate the following:

Surface finishes of 0.00011" (.003 mm)
Roundness values of .000009" (.00025 mm)
Size control ranges of .00020" (.005mm)
Production rates of 4- 6 over comparable grinding operations

Hard turning is a technology-driven process that requires certain performance features of the machine tool, workholding, process and the tooling.

Improving Internal Turning In A Blind Hole

2007-10-31T08:01:00.000-07:00

Haven't posted lately, but today have time for a quick tip or two.

It doesn't matter if your using carbide inserts, ceramic inserts, or CBN Inserts, internal turning in a blind hole brings about the problem of chip evacuation. When the cutting tool reaches the rear side wall, chips may be caught between the wall and the insert. This may cause the insert to break.

Here are two solutions I found from a carbide insert manufacturer that can eliminate cutting tool breakage:

First Solution
1. Start by grooving at the rear wall.
2. Continue by turning from the inside toward the outside.

Second Solution
Start by grooving at the rear wall. Pull the tool back to the outside. Turn the final diameter from outside toward the groove.

Carbide Insert Designation/Identification

2007-10-25T14:27:00.000-07:00

So you have a blue, green, yellow, clear box sitting on your desk, that one of the guys in the shop dropped off and said I need some more of these. Simple enough you think, I'll just order right off the box, problem is the box is smudged, and all you know is that it is and 80 degree carbide insert something or other.

Not that this ever happens. However, if you find yourself in this situation down the road, a good place to start is the ANSI designation chart for carbide inserts. This handy chart tells you whether that carbide insert is an 80 degree diamond, 55 degree diamond, or other. The insert thickness, insert tolerance, radius, clearance, hole type, and whatever other conditions may be listed at the end.

An example of a part # would look something like this: CNMA-432T DR-50

From looking at the insert designation chart, it tells me that this insert is:

1. 80 Degree diamond
2. Clearance of 0 degrees
3. Tolerance of =/-.002 to .005
4. Has a hole in it
5. Size is 1/2"- Number of 1/8ths of an inch in I.C. when I.C. is 1/4 inch and over
6. Thickness is 3/16" -Number of 1/16ths of an inch in thickness for I.C. of 1/4 inch and over
7. Has a corner radius of 1/32"
8. Has a chamfer cutting edge or K-Land

Now I know that is a lot of detail, but you get my drift. Use the sheet as a quick reference for turning tools and before you know it, it will no longer be necessary.

Thanks for reading.

-B