CNC ArticlesPhone: 516-328-3970www.technocnc.com131servomotors as standard features for precision performance, speed capacity, and machine longevity. He purchased a Techno four-axis machine with a five by six feet table big enough to handle even the longest butt stocks.Four-axis Benefi tsThe four-axis capability of the Techno machine is what makes it the solution Shuster was hoping for. If he had purchased a traditional, three-axis CNC router, it would have been necessary to continually reposition parts on the machine because cuts are needed on all sides. Although this still would have been faster than cutting parts by hand, the machine would have required constant attention. A four-axis machine, on the other hand, has dual spindles, one that holds the part and one that holds the cutter. The cutting program directs the x, y, and z motions of the cutter, as with a traditional CNC machine. But it also directs the positioning of the part. After one side has been cut, the part can be rotated, for instance, to allow access to the other side. With a four-axis machine, repositioning happens automatically so the cutting goes faster and its completely unattended, Shuster says. Using the four-axis machine, it now takes Ironwood Designs only three minutes to cut four butt stocks, compared to 15 minutes needed with the pantograph.Shuster estimates that the overall productivity of his business has increased by 60 to 80 percent since he acquired the CNC machine. It is located in the shop with the Zuckerman copy lathe, and one employee runs both machines. Shuster handles light fi nishing work. We now produce 100 pieces in four hours. Previously that took us two days, he says.The quality of the cuts is much better
with the Techno CNC machine. There is less tearing of the wood because spindle is spinning at 18,000 rpm, says Shuster. And if a cut is off by 0.010 inch, I can modify the NC program and easily fix it. In the past, the tightest tolerance he could achieve was 0.01 inch to 0.02 inch. The Techno CNC machine holds between 0.003 inch and 0.004 inch. That is phenomenal for wood, says Shuster. Now we produce factory quality pieces. You cant distinguish our stocks from the original military production except that we use a higher grade of wood.The combination of higher quality and faster production has led to an increase in business for the company. After finishing a large, two-and-a-half year contract for one gun manufacturer, Shuster has now programmed the CNC machine for a new product, a replacement stock for the Belgian FN-FAL rifle. Designed in the 1950s, this rifl e has been out of production for years. But surplus versions are being imported, and new ones are being manufactured in the US from old military specifications. Ironwood Designs is now offering replacement parts for this rifle to manufacturers, who will resell them as accessories, as well as to smaller gunsmiths who build FN-FALs for customers, and to individual owners of the rifl e who wish to retrofit it with a nicer wooden stock.In addition to this new product, for which Shuster anticipates a big demand, he plans to use the Techno CNC machine to take on projects he has long wanted to do but couldnt in the past because of time or accuracy limitations. For example, he plans to offer replacement stocks for common guns such as hunting rifl es that are far more easier to install than those that are currently available. Most replacement stocks come semifinished. The sides A shot of the shop where gun stocks are held.are carved but they have not been sanded so tool marks are visible. The gun owner has to fit the rifle to the stock, a process than can take hours of filing. For those who arent experienced woodworkers, theres the danger of damaging the stock. Shuster plans to cut these stocks on the CNC machine for a level of accuracy that has been previously unavailable. My kits will be innovative because they give you drop-in fit, he says.The acquisition of a four-axis CNC router improved productivity and accuracy at Ironwood Designs. The result is an increase in business. We no longer advertise and yet our volume keeps increasing, says Shuster. With a four-axis Techno CNC machine, were now able to produce replacement stocks for anyone who wants one.