Disposable PCD tooling.

A HARDER CUTTING MATERIAL BECOMES EASIER ON THE WALLET

Once widely considered cost-prohibitive, PCD tooling is not only becoming more affordable through increasingly efficient application of the material, but also through increased user acceptance.

Polycrystalline diamond (PCD) cutting tools have been a recognized tool material for years, yet have not found wide acceptance in the woodworking industry primarily because of their high price as compared to carbide and high-speed steel tooling. Quite frankly, many companies looking at diamond tooling have suffered from "sticker shock."

Increased demand and more efficient manufacturing techniques have helped reduce the cost. The lowered price plus the advantage of lower production runs have more woodworking operations taking a hard look at what PCD tooling has to offer.

"Anyone who feels they are on the merry-go-round in keeping up with worn tooling should consider PCD tooling," said Glenn Mihalovic, sales manager with Gladu Tools Inc. "It's remarkable how much more production can be obtained out of existing machinery if you are not constantly interrupting the production cycle to change a dull tool."

Factors including recognizing diamond tooling benefits, affordability, and product growth are all important issues to be familiar with when considering PCD tooling.

Diamonds can be a best friend

The benefits of PCD cutting tools are numerous from a production standpoint if utilized properly. Mistakes in identifying the proper application for PCD tooling can be expensive lessons, though. Tooling suppliers warn that PCD tooling is not for every manufacturer.

"PCD tooling is by far the easiest tool medium to cost justify when producing many parts," said Scott Erickson, vice president with Leuco Tool Corp. "But for the smaller producer, it would take years for PCD to pay for itself."

Probably one of the strongest benefits of PCD tooling is its ability to cut for long periods of time without needing replacement. Although it is difficult to gauge the life expectancy of PCD tooling because of each individual application, many tooling suppliers said that PCD tooling can last as much as 80 to 1,000 times longer than carbide or high-speed steel tooling.

Some factors that can affect the life of a PCD bit are material being cut, vibration, feed rates and touter spindle speeds.

One material that many tooling manufacturers mentioned ideal for PCD machining is MDF because it is a homogenous material with a relatively consistent construction and is free of foreign materials such as knots, stones and other foreign matter.

"The use of PCD router bits for machining MDF cabinet doors is growing," said Andy Willbond, technical coordinator with FS Tool Corp. "PCD performs well when machining MDF and companies can make a cabinet door from a single sheet of MDF on a CNC touter compared to the traditional five-piece solid wood construction."

Vibration is also an enemy of PCD cutting tools. Because they have a tendency to be very brittle, excessive vibration can cause PCD bits to shatter.

"In router applications, it is critical to have spindles, bearings and collets in good operating condition. A worn spindle can cause the shaft to wobble or 'run-out' and could cause the bit to bend," said Dave Riguzzi, vice president of engineering with Onsrud Cutter Inc. "It's also advisable to have a good hold-down system that will not allow the part being machined to move."

Feed speeds are also critical because uneven load pressure from hand feeding can cause unnecessary stress on the bit or blade and can lead to tool failure. (see sidebar, p. 110) Ekstrom, Carlson & Co. recommends machining parts using some type of control feed. Check with a tooling company representative as to which feed speeds are best for each specific material being machined.

With router bits, rate of cut and spindle speeds can determine the life of PCD router bits.

"Feed speeds are generally governed by the number of wings on the cutter and the diameter of the bit, but it's best to check with your tooling supplier," said Colin Standish, O.E.M. sales manager with Leitz Tooling Systems Inc. "With PCD bits manufactured in Germany, it's the law that they have the maximum rpm marked on the tool."

Throw away diamonds?

Similar to carbide insert tooling, tool makers are also manufacturing disposable, or single-use PCD cutting tools which have greatly reduced the cost while still providing long life. Arguably the biggest deterrent to a wider use of PCD tooling has been the cost.

"The argument that the initial investment is a deterrent was also offered in the 1940s with carbide-tipped tooling," Mihalovic said.

Because of improved technology in the manufacturing of PCD tooling, manufacturers have been able to pass savings on disposable diamond tooling to customers.

"The most significant development in PCD tooling, in my opinion, is the better use of the raw material itself," said Erickson. "Manufacturers of PCD tooling have developed ways to more effectively dissect a PCD tablet, enabling them to reduce the tool costs to the end user. Although these types of tools are described as disposable, in most cases they can be serviced as many as three times."

Low cost diamond tips can now be produced by slicing thin strips of PCD with its tungsten carbide backing from conventional PCD blanks. These strips are oriented at 90 degrees to the existing manner in which POD tips are brazed, according to Willbond.

"This has the effect of exposing only a relatively small area of PCD to become the cutting edge," Willbond said. "When this is compared to the standard practice of brazing large semi-circles and segments of PCD, there are considerable savings in the amount of PCD used to produce a tool. The savings are in the order of two-thirds the original costs. It is true that tools produced using this new technique can only be sharpened once or twice, compared with 10 times of conventional PCD tips, but the lower costs are attractive to many users particularly where there is risk of chipping of PCD through type of application or handling."

"SU (single use) or disposable tooling for high-volume applications can be used where profile integrity is of optimum importance is growing," said Mihalovic. "These tools are not made any different. Tool makers have simply passed on the cost effectiveness of their CNC equipment to their customer."

How much less expensive disposable diamond tooling is hard to pinpoint, however.

"It's hard to say what the savings are from disposable tooling," said Standish. "Controlling factors of price include the type of profile, the number of diamonds in the bit and the number of bits produced in the production run."

Lots of potential

When asked where the potential growth areas for PCD are, tooling suppliers varied in their responses. Some of the opinions of new developments in PCD cutting tools may come as a surprise.

"There are applications (for PCD) relating to edgebanding that should be looked at by every woodworker," said Erickson. "Top and bottom trimming of laminates are an example. There the material being machined is homogenous and the resulting tool life is excellent."

Many tooling suppliers who responded were split in their responses when asked which type of PCD tooling market was growing the fastest. Respondents mentioned PCD router bits and circular saw blades as the areas which would see the strongest growth in the future.

"Router bits, from a sales perspective, are growing fastest," said Mihalovic. "They are growing for two reasons: the versatility of the CNC machinery available on the marketplace is very significant and the addition of lineal parts being made from composite material such as MDF mouldings is causing diamond tooling to be more in demand."

Some tooling suppliers said that circular saw blades will also experience greater growth in the future.

"PCD saw blades now offer increased stability in their bodies," said Phillip Kauffman, president of Henderson Diamond and Carbide Inc. "It has finally been proven that PCD panel blades are extremely cost-effective when measuring them to their counterpart carbide blades."

Available diamond tools

The following is a review of some cutting tool equipment available to the wood-working industry. For more information, circle the corresponding numbers on the Reader's Service Card. For a more comprehensive overview of the cutting tool market, consult the 1995 Red Book Annual Buyer's Specification Guide.

Syndite CTC002 polycrystalline diamond from DeBeers Industrial Diamond Div. is reported to cut cleanly and without chipping through 1,100,000 linear meters of chipboard before regrinding was necessary - which the company says is approximately 150 times the life of tungsten carbide tipped blades in the same operation. DeBeers adds that the annual cost of regrinding PCD is around half the monthly regrinding cost for tungsten carbide.

The diamond/carbide multi-profile shaper set from Gladu Tools Inc. combines the high payback of diamond with the versatility of carbide insert tooling. The multi-profile shaper set features two stacking heads: a diamond/carbide stacking head for grooving and profiling rails and stiles with the grain, and a carbide insert stacking head for forming the tenon ends and coped shoulder profile in the cross grain.

Henderson Diamond and Carbide Inc. manufactures a complete line of poly-crystalline diamond panel saw blades, with matching scoring blade. It also offers PCD sizing saws for combination edge-banders and tenoner machines. The company guarantees that the tools will be cost effective when compared with carbide saws.

Dia-economic disposable diamond router bits from Lach Diamond Inc. are offered in inch sizes and metric sizes with both right and left hand rotation, which are suitable for European routers.

The Leitz Tooling Management System from Leitz Tooling Systems Inc. uses a programmable micro chip embedded in the tool holder which carries all the tool related data. When the tool is installed, the reading head provides the data to the computer and appropriate machine adjustments are made automatically. The system is available for CNC routers, tenoners and moulders.

Diamax disposable diamond shank-type tools from Leuco Tool Corp. now include straight flute touter bits, scoring saw blades and rabbeting cutters. Shank sizes are 1/2 in and 5/8 in. with a cutting length of 1 in. Scoring saw blades for double-end tenoners are available with 24, 28 or 32 teeth for various feed rates. The jointing/rabbeting is for shaper machines and can be used to machine laminated products and solid woods.

North American Products offers a complete line of cutting tools and service to meet customers' service demands. The Diamondizer series is reported to be affordable and allow the user to experience the benefits of diamond tooling.

CNC diamond router bits from Riverside Tool Inc. are reported to achieve long life and higher production. Riverside says the stager of the tips and the ability to put shear where it is required are achieved without compromising the quality of the cut.

Saber Diamond Tool says the Maximizer series of diamond tooling provides economic use of diamond in production where tolerances are critical. The series features both up-shear and down-shear to provide clean, chip-free cuts, ability to be resharpened two to three times and a diamond plunge tip.

Tel-Con Industrial Diamond Tools manufactures a variety of standard and custom diamond cutting tools including cutterheads, bits and saw blades. These tools are capable of machining all types of wood and composite board products including MDF, particleboard and oak.

Polycrystalline diamond (PCD) profile cutters from Winco Industries Inc. are diamond tipped profile cutters which can run at faster speeds than conventional tools, according to the company. They can be sharpened several times, and additional benefits include higher material removal rates, improved dimensional control and more uniform surface finish, the company says.

Other available tooling

Spiral heads from Bimex Inc. can be used on moulders as well as shapers and other machines. Heads are especially useful for companies running S4S. Carbide knives used are of the type that have four cutting edges and Bimex says the heads offer reduced noise.

GUHDO USA has a complete line of multi-profile insert router bits for CNC machining centers. It has seven different types of cutters for various profile applications; each can produce several profiles by changing the inserts and matching backer plates. The cutters can produce profiles on outside panels, inside door profiles, rosettes, V-grooving, decorative carvings and moulding profiles.

The Shaper System Set from CMT Tools includes 14 pairs of precision-ground HSS cutters, a cutterhead in 3/4- or 1 1/4-in. bore, and moulded case and tools. Install any of 40 cutter profiles, tighten the screws and go to work. Switch the profiles without removing the cutterhead and mill a totally different shape.

Counterbore tooling from Continental Counterbore is manufactured from a special made steel, precision finished and tipped with a carbide formulated to provide the best performance possible under the impact and abrasive conditions to which the tool is subjected.

Courmatt Int'l Inc. offers a four-fluted (two up sheer, two down sheer) Herringbone solid carbide shank tooling. Feed rates of 1,500 ipm have been achieved with diameters from 1/4 to 3/4 without various cutting lengths. Custom sizes are also available. Courmatt also provides tables for feed rates with consideration for rpm, horsepower, tool diameters arid tool geometries.

The Whispercut cutterhead from Drake Corp. can be used on all planer, moulder and shaper surfacing applications. Drake says its spiral-type cutting application minimizes cutting pressure. Helical machining and tooth spiraling minimizes noise levels while using four-sided inserts to allow for cost effectiveness.

E.W. Tooling specializes in designing and developing tooling for each customer's specific application. E.W. Tooling says benefits include cost effective, precision, quality tooling for CNC routers, tenoners, moulders and shapers. Available tooling materials include high speed steel, carbide, tantung and diamond cutting tips.

The ECCO Bi-Shear solid carbide tool from Ekstrom Carlson & Co. has been designed for edge finishing applications where a fine finish is required on both top and bottom edge in one pass. Benefits include less vibration at the spindle head, which reduces spindle bearing wear, and the availability of a Z-100 Dura-Plus coating which is reported to provide increased hardness and lubricity.

The Dispoz-A-Blade system from ESTA-USA Inc. is reported to offer fast, easy installation in any planer or moulder cutterhead. The blades come in high-speed steel and specially formulated Kobalt steel to further extend the time between blade changes. Additional benefits include no need for resharpening and uniform knife-to-knife weight for vibration-free operation.

The Centra-System from FS Tool Corp. is a unique self-locking system for planing heads. The centrifugal self-locking system automatically clamps reversible insert knives for quick change, productivity and constant cutting diameter. Knives are available in specially treated high-speed steel and micro-grain solid carbide.

A full line of European disposable and resharpenable insert tooling for all current European moulders, saws and other modern woodworking equipment is available from Freud Inc. The company says it uses special grades of steel and high strength aircraft aluminum to make the precision cutting heads. Disposable tip knives feature multiple cutting edges and computer designed cutting angles provide maximum cutting finish. Resharpening can be performed on a flat grinder.

Integra Tooling and Accessories stocks a variety of brad point and through-hole carbide tipped boring bits ranging from 4mm to 12mm including 1/4-, 3/8-, and 1/2-in., with 8mm shanks. The newest items include solid micro-grain spiral router bits and insert knives.

Anti-kickback router shaper bits for table routers from LRH Enterprises Inc. include the Cabinet Door Series, consisting of 14 assorted bits used in the making of various cabinet doors and frames. These carbide-tipped bits are to be used on table routers with multiple-speed routers. Only available with 1/2-in. shanks, all bits are spin-balanced for vibration- and chatter-free performance. The male and female sets will do both raised panel and glass panel doors.

Markay Cutting Tools Inc. offers custom and standard tooling, including brazed cutters, router bits and saw blades, replaceable inserts and diamond tooling. The company also supplies service work including diamond sharpening, retipping and reconditioning.

The mortising compression spiral router bit from Onsrud Cutter Inc. is reported to be able to pull chips out of the slot with its short up spiral portion and the down spiral portion holds the melamine against the MDF to allow a clean cut without chipping.

Profile Technology offers custom engineered brazed and insert cutting tools. Insert tools can be either dedicated or multi-purpose in design. Multi-purpose heads allow similar profile inserts to be used in a common head using backing plates ground to the insert profile. Multi-profile inserts are also available as well as grinding profiles for competitive heads.

Solid carbide rough end mills from SGS Tool Co. feature full sinusoidal grind for optimal edge strength, give faster chip removal rates and reduce production time, the company says. Stocked in either TiN or TiCN coatings, the roughing end mills are available in 1/4-, 5/16-, 3/8-, 1/2-, 5/8-, 3/4-, and 1-in. cutting diameters.

The Vario Cut shaper cutter set from Stehle USA Inc. is a cutter set which features replaceable knives and is capable of producing tongue and groove profiles, adjustable radius corner timber, and rebate work as used for doors. The set is available with either high-speed steel or carbide knives and is delivered in a plastic carrying case.

Super Thin Saws Inc. has developed a line of thin kerf, glue-joint ripsaw blades for straight-line and gang-rip machines. The blades are commonly used in modern rough mills, and have kerfs from 0.80 in. to 0.115 in., depending on specie mix, stock thickness and feed rate.

Vermont American's patented Plug-Out universal arbor system converts the most standard bimetal hole saws to plug ejecting models. The universal adapter fits the arbor hole of standard saws. Insert the proper arbor, cut the hole, reverse the drill and the plug is ejected automatically. Two arbors and multiple adapters are available.

The Barker-107 Velepec edge forming bit from Wesley Tools Ltd. has been designed to expand edge forming capabilities in any solid surface material or wood. It features 1/2-in. shank, 2 3/4-in. diameter, 1 1/2 in. cutting length and two flutes. The surgical carbide tip enables it to hold an edge longer and is American made.

The solid carbide small pilot flush trim bit from Whiteside Machine & Repair Co. Inc. is manufactured especially for trimming the inside of a shallow dado that has been laminated. The conventional style solid carbide flush trim will not allow a user to trim in a shallow dado because of the length of the pilot.

The BAK-PAK 2 knife system from Wisconsin Knife Works offers users high production levels and longer tool life than brazed carbide tipped knives, according to the company. The six-step system provides resharpening capabilities for longer tool life and value added design features.

RELATED ARTICLE: THE DO'S AND DON'TS OF DIAMOND ROUTER BITS

1. DO NOT allow the router or work-piece to become loose. This will cause the diamond edge to chip. Everything must be rigid. The more stable and vibration-free, the longer the diamond tool will last.

2. DO NOT cut any metal that is ferrous; steel, iron, etc. This will ruin the cutting edge immediately.

3. DO NOT force the router bit to overload or plug up. This will cause severely high heat and in turn, the touter will turn hot and melt the solder that is holding the PCD tip to the steel body, thereby resulting in tool failure.

4. DO try to avoid intermittent cuts because this causes chatter and vibration. This causes the cutting edge to chip.

5. Climb cut only under a power controlled unit. DO NOT climb cut by hand because free hand climb cutting tends to grab the part and overload the PCD tip, resulting in tool failure.

6. DO try to machine parts by using some type of control feed. Although free hand routing is possible, a CNC controlled machine operation with a very strong secured part will insure longest tool life.

7. DO eliminate as much as possible to make tools last up to 10 times longer.

This list of diamond tooling maintenance suggestions were provided by Ekstrom, Carlson & Co.