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Innovative Eureka System Shows Potential for Thin-Kerf Gang Saws
Saw Blade Innovation: Eureka Saws develops circular saw blade and spacer for gang saw systems that are designed to provide air cooling and allow for thin-kerf gang sawing.
By Dr. Ed Brindley
Date Posted: 8/1/1999
ELYSBURG, Penn. — Eureka Saws Inc. has developed a new circular saw blade and spacer for gang saw systems that are designed to provide air cooling to the blade, spacer and arbor, allowing for thin-kerf gang sawing.
Eureka’s new Ventilated Air Cooled Cutting System, tested on a 12-inch blade, performed with a kerf of 0.096-inch while sawing 6-inch material, according to the company. The new system was tested over four months at two locations in Pennsylvania and one in Kentucky. The new blade and spacer have been run on Brewer Inc. gang saws.
In addition, Eureka already has begun testing a 10-inch blade with a target of 0.082-inch kerf on a Brewer Midas .099™ gang saw.
Unlike thin-kerf gang saws that use lubricants or guided blades, the Eureka system is designed to run more like conventional gang saw blades.
The new system is designed so that the heat generated within the arbor, spacer and inner hub of the blade is reduced by the ventilated design of the blade and spacer combination. The spacer has ventilating holes that carry air through the outer edge of the spacer through the side of the spacer and to the blade. The blade construction is unique for two reasons. It is made with a thicker, stronger center hub plate, equal to a saw blade 0.110-inch thick, and a thinner outside rim that actually enters the cut. Like the spacer, the center hub plate has a series of ventilation holes. The cooling system brings air through both the spacer and the blade, working in tandem to cool the blade, spacer, and arbor.
The significant cooling effect of the Eureka system is what makes it work. As those in the pallet industry know, heat is the enemy of sawing with circular blades.
Previous attempts to make thin-kerf saw blades under 0.100-inch kerf to cut 6-inch material have failed because the saw blade required a 0.065-inch body; in a 12-inch blade, the 0.065-inch body typically has failed because of the thinness of the blade and the instability caused by high operating temperatures.
Eureka, which has applied for a patent to protect its new design, introduced VACCS, for Ventilated Air Cooled Cutting System, at the recent Forest Products Machinery and Equipment Exposition in Atlanta, also known as the Atlanta Expo. Alex Manzo, president and chief executive officer of Eureka, gladly shared the new technology with anyone who came by the company’s booth. Like many really good ideas, this new concept came to Alex when his mind was free to dream, not while he was sitting in front of a computer-assisted design system.
The new Air Cooled Cutting System was designed by Alex while the special jigs, figures, holders and processes were designed and made by Eureka’s senior machinist, Roger Billman. A team of Eureka employees handled the servicing requirements, such as hammering, tensioning, grinding and sharpening.
"The blades run cool to the touch while providing a sanded-like finish on the boards," said Alex. "The finished cut is held to within 0.005-inch to 0.010-inch of target size."
The system out-performed expectations in test runs. Alex smiled as he described the initial tests. "After a cant cleared the planer, the noise associated with gang sawing never developed as the cant contacted the blades. We thought the machine had quit running until cleanly cut boards came out of the saw. The blades were so quiet we could hardly believe it. It is another plus that we had not counted on."
Eureka worked closely with Brewer in developing the new technology, and Brewer modified its machines to accommodate the new Eureka system. The Brewer patent-pending thin-kerf gang saw designs allow a cut-to-length cant to be completely free of the sizer before starting the cut. Thus, vibrations from the sizing operation are not directly transferred to the cutting operation through the cant.
Alex is quick to point out that lumber sawing is a marriage between the machine and the blade, and the new Eureka system will not achieve the desired results if it is not run on the right machine. It has only been tested on new Brewer machines designed specifically for the Eureka system. Alex does not extend his performance claims to older Brewer machines and machines of other manufacturers. In addition, the new blades may only be serviced with special Eureka machines.
Now that Eureka has achieved kerf under 0.100-inch when cutting 6-inch material, the company is working to adapt its patent-pending technology for edger saws, trim saws, and cut-off saws while pursuing further kerf reductions in gang saw sawing.
While new machinery models are common, truly new engineering and design concepts are somewhat rare. The new Eureka system reminds me of the strobe saw, which proved to be a significant development in saw blade technology. The difference with Eureka’s approach is in the blade. The design is truly revolutionary.
From the 1970s into the late 1980s, gang sawing with circular blades was the preferred method of sawing hardwood cants and rough hardwood pallet lumber. Bandsawing with thin bands caught the attention of pallet manufacturers because the reduced kerf allowed a greater yield for some cuts. The bandsawing concept was certainly not new, but the thin blades used in horizontal thin-kerf narrow bandsawing was a new wrinkle that captured a large segment of pallet sawing, both softwoods and hardwoods. The problems of sawdust and slower cutting speeds were tolerated because of the trade-off from greater yields.
Developments to reduce the kerf association with gang sawing have continued. Claims of gang sawing with 1/8-inch kerf have been exceeded by some 0.100-inch kerfs through 4-inch material.
For more information about Eureka’s new system call Alex at (800) 672-3388 or (570) 672-3390. For information on the new Brewer saws, call Brewer at (800) 345-6516.
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