Beta Blog

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

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

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

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

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

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

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

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

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

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

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?

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

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

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

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

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

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

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

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

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

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

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)?

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

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?

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?

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

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.