Less Scrap, Faster Machining

 

Have you scrapped any jobs lately – or was it the machine itself this time? Well, if your answer was "yes," you can rest assured that you weren’t alone. Most shops have scrapped, or at least seriously damaged tooling during manufacture – usually while cutting 3D surfaces or rapid traversing towards the billet.

Mason Pinder had no difficulty justifying investment in VERICUT after scrapping an expensive mold tool in 1996.

 

Mason Pinder (Toolmakers) Ltd. is part of the Polypipe PLC group of companies in the UK. They specialize in producing molds of up to 20 tons for pipe joints, consumer goods, toys, and automotive products.

 

The company is based in Thorne, near Doncaster, Yorkshire in the Northern part of England. They have four NC programmers and 10 machine tools including Rambaudi, Giddings & Lewis, KO Ming, Leadwell, Hurco, DMG DMU50.

 

"Most of our jobs are one-offs," says David Mason. "We can’t afford to prove out every job on the machining side and welding up gouges isn’t a favorable option. It made sense to go down the software route and get the job right before any tool touches it."

 

Mason Pinder chose VERICUT because of its reliability and ability to prove out the post processed data, not just the CAD/CAM’s internal CL data. "We concentrate on axis verification. We had a problem in that the C-axis would have to unwind after two revs, but it was nice to be able to verify the tool retract and unwind on VERICUT. It’s also nice to be able to verify over-travel when you are getting near the axis travel limits," says Mason.

 

"VERICUT has made it much easier to see what’s going on when we’re using our new DMG DMU50V 5-axis, high speed machining center," Mason added.

 

Mason Pinder also takes advantage of VERICUT’s feed rate optimization capabilities. "We’ve seen 50% reductions in cycle times when roughing large jobs," says Mason. "When we first started using OptiPath we concentrated on the feed rate option; now we use the constant chip thickness capability. With jobs up to 200 hours long, 50% saving is significant – like having another machine tool."

 

It also optimizes spindle speeds, relevant to high speed machining operations.

 

Unlike reactive hardware solutions, OptiPath automatically knows what area of the tool is in contact with the workpiece, load on the tool and cycle times. Its power comes from modifying the G-Codes to increase feed rates as less material is being cut, and decrease them to protect tooling as more material is being removed. For example, when cutting three 20mm deep square pockets, in a row 50mm apart, OptiPath ramps the machine feed up to the maximum until the tool is just within a safe distance of its position. Once on position, the first picket will be cut according to the programmed tool path, but with optimized feed rates. When finished, the tool will move to a safe clearance and fast feed to the next pocket, where the process is repeated.