by Mary Scianna
Profile of toolholding success in high speed machining
Machining speeds: Up to 46,000 rpm on Matsuura and Okuma machining centres
Toolholders: Rego-Fix ER11 collets and PowRgrip toolholding system
High speed machining with speeds of up to 50,000 rpm isn’t for everyone, but if your manufacturing requirements demand it, you need to invest in the right technologies to ensure success: a machine that can handle the speeds and tooling that won’t break off during machining. Ensuring your tooling won’t break off means you have to have the right toolholding system in place. Shop Metalworking Technology approached manufacturers involved in high speed machining and asked about their success strategies using toolholders in high speed machining applications.
If you service a market that demands precision and quality, you can’t compromise on the tooling required to make such parts, especially when those parts are aluminum or titanium aerospace components that cost thousands of dollars. And when you’re machining at speeds of up to 46,000 rpm, you’d better ensure that your tooling can handle the conditions.
So when B&R Custom Machining in Cambridge, ON, began to experience precision problems with high speed machining in collet and shrinkfit toolholding systems for tighter tolerance work being machined on high speed machine tools, it had to consider its options.
“We tried two different shrinkfit systems and seven different shrinkfit manufacturers,” explains Nicholas Free, toolroom manager and general machinist at the company. “They were precise at the beginning, but less than ten cycles in, they began to increase in T.I.R. And setting the tools was also time consuming compared to collets. As our parts demanded tighter tolerances, our requirement for more precise toolholding increased.”
B&R reached out to one of its tooling suppliers, Triumph Tool, which suggested Rego-Fix toolholders. With support from Rego-Fix’s representative in the area, John Belder, B&R tested Rego-Fix’s PowRgrip toolholding system.
“We tested the PowRgrip on our Matsuura machine, running at 46,000 rpm and that’s when we realized how good the toolholding system was. Our tool was sticking out 25 times the diameter and it was less than 50 thou of an inch and it worked; no breakage and we got the accuracy we needed. We haven’t had a pullout yet and T.I.R has been .0003 at its worst. Our cutters have less chatter in the PowRgrip than they had in the collets or the shrinkfit systems we had been using. And we’ve dramatically reduced tool setting time too when compared to shrinkfit.”
Free says the Rego-Fix toolholders are more expensive than previous toolholding systems the shop has used, but says they can’t afford not to use the higher end technology.
“We made a significant capital expenditure for toolholding and how do we justify it? Our quality just demands it. We can’t afford to make poor parts so it’s not a matter of whether or not we can afford the tooling; we need to do it and we’ve seen the results.”
He cites an example of how the company has easily justified the cost of the new Rego-Fix toolholders.
“We used a shrinkfit toolholder that cost about $300 on a $3,000 titanium part and the tool pulled out. We tried a higher quality shrinkfit system that cost $500 and the tool still pulled out. So that was $6000 of parts lost. We then used the Rego-Fix toolholders and those parts didn’t budge and that blew me away. So right there we could have saved $6,000 just by going to a more secure toolholding system.”
Free says the company is so impressed with the performance of the PowRgrip that the shop is “quickly progressing towards using mostly Rego-Fix toolholders.
“We’re impressed by the service from Triumph and by the toolholders themselves. It has all been a pleasant change for our shop. We have happy customers and new customers coming in. We need to ensure our tools and holders can create the quality of parts our customers expect of us. If that means a complete conversion to Rego-Fix, so be it.”
B&R Custom Machining is an AS9100 certified machine shop with customers around the globe. The shop is equipped with the latest Matsuura and Okuma five axis machining and multi-tasking CNC machines. The Rego-Fix toolholders include HSK40 A, HSK63E, BT and CAT taper arbors holding end mills up to 25 times diameter in aerospace materials such as titanium and aluminum.