Getting a grip on toolholding

Quite a bit of money is spent on tools each year at Applied Engineering Inc., so the optimization manager was pleasantly surprised when a toolholding system began doubling tool life, cutting overall costs.

“We’re always looking at ways we can improve our processes,” says Greg Husman, the company’s optimization manager. “What we’ve found is that balancing and heat-shrinking our toolholders gives us repeatable and predictive results.”

Based in Yankton, South Dakota, Applied Engineering is a 165-employee shop that specializes in short- and long-run aluminum components for industries including medical, military, commercial communications systems, and aerospace and defense. The company also launched its own line of compound bows, diversifying in a different market.

With dozens of high-speed horizontal machining centers, machinists at the company know that proper toolholding is critical to extending tool life and a key factor in machining accuracy and repeatability.

However, until recently, proper toolholding came at a high cost.
 

Pressure is on

Husman notes that they had been spending $40,000 per year on parts for its existing toolholding system, which required specially designed collets to be pressed into toolholders. Though the system achieved decent runout, the costs were difficult to justify. That is when a team began searching for a comparable, less expensive system. They found one while visiting the Haimer USA booth at the International Manufacturing Technology Show (IMTS) 2012.

Haimer’s system claims to have higher gripping torque, accuracy, and balance repeatability than other systems. A key difference is that it uses heat rather than collets or hydraulics to grip a part. The toolholder heats up, and the cutting tool is inserted. After the toolholder cools for 30 seconds, the toolholder and cutting tool become virtually one piece.

Engineers tested the Haimer system and experienced a dramatic improvement in runout, gripping force, and balance – the three main variables in toolholding on a consistent basis. Tool life increased from 80 parts to more than 600 parts.

“The Haimer system paid for itself in less than a year,” Husman says. “Not only have we increased tool life on many of our tools, but the quality of our parts is increasing just from the repeatability of tooling. We’ve also noticed an improvement in surface finishes and cycle times. Though we still use both systems in order to remain diversified, the Haimer system is a better fit and much more economical.”

A key benefit was balance repeatability and balance options. Because there are no moving parts with the shrink-fit system, additional fine-tuning is often unnecessary. However, the company decided to purchase Haimer’s modular balancing system to improve tool life for its other toolholding system.

“The balancer alone has helped us beat tool life expectations by at least 20%,” Husman states. “When combined with the shrink-fit system, which helped us improve runout from 0.0007" to 0.0002", we can achieve near-perfect conditions. Haimer’s balancer can be used for any of our toolholdling systems; the heat shrinking just takes it one step further.”

Because of the high gripping torque of the Haimer shrink-fit system, machinists also noticed a reduction in scrap – cutting waste in half last year.

“We’ve been very pleased with the products and service offered by Haimer USA,” Husman says. “They provided training on the shrink-fit system and balancer soon after delivery, and they have been quick to answer additional questions. They’ve been very good to work with.”

Haimer USA
www.haimer-usa.com

Applied Engineering Inc.
www.appliedeng.com