New Swiss Turning Technology Boosts Productivity For Contract Manufacturer

Roy Mendoza of RM Precision (Laverkin, Utah) has always been a cam man. He makes his own layouts, cuts his own cams and makes his cam-driven machines sing. He tried a CNC screw machine once and was so disappointed that he had the manufacturer take it back. But, he made a promise to himself that he would apply current technology when warranted. "I always said that if I found a CNC that did what a cam can do, I would buy it," he says. "I found that at Tornos in the DECO 2000 machine."

Technically, the DECO is not a CNC, but a PNC (parallel numerical control), and that is the difference. The PNC control was developed by Tornos using a FANUC system that allows each machine axis (up to 12 on 20 mm DECO models) to be governed by its own chip, which carries the part program. The parallel execution of axis and machine function commands reduces unproductive time to a minimum, boosting machine efficiency. One gain from this technology is that the DECO 2000 machines can have four tools cutting simultaneously: two turning tools and an endworking tool at the main spindle, and a backworking tool at the subspindle. Typical CNC Swiss-type machines generally take three times as long to produce a part because they do calculating and interpolating, as well as more stopping and starting, between functions. The PNC-DECO cuts out the dead time, making it as fast as the cam-driven automatics.

"The more complex the part geometry, the greater the productivity rewards of the DECO," states Mr. Mendoza. A case in point is a ballpoint pen part that used to be produced in a machining cell at RM Precision. The cell consisted of five machines — three CNC lathes, one drilling and tapping machine, and one CNC milling machine. The average production was 200 per day. On the DECO 20 mm machine it is 600 per day, consuming just one machine, not five.

Naturally, working with cam screw machines all his life, Mr. Mendoza had a learning curve with the new machines. "It was hard for me to learn the programming, but the Tornos people were extremely helpful. There was one Friday when one of their technicians stayed on the phone with me most of the day, walking me through the programming sequence. If that wasn't enough, he gave me his home phone number in case I had any more questions over the weekend. That to me speaks volumes about their commitment to customers."

Mr. Mendoza says the first job he put on the new machine was one that averaged 700 parts a day on cam machines. Within the first week of running it on the DECO, he averaged 4,000 a day — a productivity improvement of 500 percent. Another ball point pen part, which turns the refill cartridge, used to be produced at a rate of 200 a day maximum on the cam machine. On the PNC, the rate is 5,000 plus.

DECOs are more productive, according to Mr. Mendoza, because of the machine accuracy and automatic bar feeding. The company can run one for the full 24 hours a day, compared to 10 hours a day on the cam machines.