I've been using the new version of Tormach's Speeder for about a month now and have been very impressed with it. Compared with the original version it still has a 3:1 speed multiplier, but there have been some design changes including high speed balancing of the internals that greatly increase its smoothness when running. I've probably got more than 50 hours of run time on my original Speeder and have used it to make many aluminum parts to save machining time thanks to the increased spindle speed. However, I usually had to 'fine tune' the actual speed to avoid annoying resonances that I was afraid would affect surface finish. With this new Speeder, though, I've been running as fast as my carbide cutters will allow and have been getting beautiful surface finishes at any speed I choose. Enclosed are some photos of some parts I've recently made.
The first photo is a re-do of the connecting rods for my 9-cylinder radial engine I previously machined using my original speeder but recently realized I had a design error causing an interference problem. Machining here was on both sides of the workpiece with 5/32" cylindrical and ball cutters. The only modification I made to my original program was to increase the rpms to 15K from my original 12.7K and I left the feedrates at 7 ipm. What you see in this photo holding the parts in the frame is an Epoxy gel I use to machine 2-sided parts. I machine to half depth from one side, apply the gel to that side and flip the part over to machine the backside. The epoxy holds the parts in place after they are cut free with from the workpiece with a contouring operation. Heating the epoxy with a heat gun allows the parts to drop free with no residue to clean off or filing to clean up.
The next two photos show the fuel pump enclosure for the same engine. The issues with this part were the deep cavities that required a 1/8" cutter with over 1" stickout in order to machine the internal details. I settled on 15K, 7 ipm and and a conservative .03" doc after some experimenting to minimize chatter from the excessive stickout. Machining time was 1.5 hours (vs 4.5 hours without the Speeder). [The motor and pump were robbed from my son's junked RC car fuel filler.] - Terry