Quote Originally Posted by Jim Dawson View Post
Is it possible to spiral in using a relieved endmill? About 0.125 per revolution. That's how I normally finish a bore. Leaves a nice finish.
We ordered the heat shrink system and tools from Techniks via Ellison yesterday, so we're hoping that ships fast, and we'll give it a shot. It was like $10,000 for the package of tools and the machine, but we got a few spare holders for other application solutions that could pop up.

One of the end mills we bought is relieved, still subject to the 2.85" stick out required for the job here, and in the hydraulic holder the 5" shank puts it at like 3.150" minimum stickout. I think you are correct and we could probably .125" helix it, and that would put us at 11 passes to get it to finished, and we're running 2 at full depth or we tried up to 5 step downs (which for two bores per part adds one minute to 18 minute cut time) and it wasn't smooth (steps) and we want to figure out a way to produce the ~27 parts in this family efficiently so we had had better cutting properties with the rogue end mill, so we were thinking, get the heat shrink in, drop the 3.15" stick out to 2" with the slim necked holder and 2" flute 4" OAL 45 deg helix rogue end mill, and I think we will be able to full depth cut this in 2 passes, using one pass to normalize the wall stock from the rough, and one to finish it without chatter. We're looking to get good enough that the process is stable across the 27 parts, AKA not requiring different processes for different parts.

We could bore it but I don't see any boring tools that look right, and I'd probably have to apply it to some engineer at Big Kaiser, and buy 3 boring tools per machine (3 machines) for the 3 different hole sizes out of desire to keep the process able to go part to part without requiring operators to be really skilled and on the ball adjusting those tools and stuff, and even then the offset isn't in the control so it's nuanced. We're hoping to mill the bores in an efficient run time. That could cost more than the heat shrink solution to get a similar level of automation and speed part to part.