Is anyone else having issues with runout in TTS R8 collets? I've ordered 2 of them after forgetting to tighten my old one and destroying it and a tool holder. The 2 new ones both have .0015 to .002 of runout as close to the spindle as I could measure and get significantly worse with distance. One was from LittleMachineShop and the other direct from Tormach. A generic Chinesium 3/4 R8 measures around 0.0005, but doesn't allow all my tools to seat against the spindle.
Ignore the beeping, that's the VFD interfering with my probe interface. I haven't programmed Mach to turn on the probe damping signal with the spindle yet.
Other toolholders and a generic 3/4 HSS endmill give similar readings in all 3 collets. It seems the TTS collets are both angled and off center.
Anyone have a good solution/alternative? I'd really like to stick with the TTS, and sunk a ton of work into an air power drawbar already.
Many (many!) years ago, Tormach noted that their TTS collet was just a standard R8, ground flat on the face. If the LMS & Tormach collets are out of spec -and the numbers you post are definitely out- just grab a good one and grind it flat (and square, of course). I do understand that not every shop has a surface grinder, but you should be able to find someone. Probably get a batch price for several that would make it reasonably cost effective.
IReminder: the TTS collet is intended to retract slightly below the surface of the spindle to index the TTS ring against the spindle, not the collet. Absolute length of the collet is not as important as long as the ring indexes to the spindle nose. A flat face square with the axis is the "right" way to do it, but squareness of the collet face doesn't determine indexing unless it prevents seating against the spindle. One could probably flatten the collet on the side of a bench grinder wheel and get a workable, if ugly, result.
If I got collets with that kind of runout, I'd send 'em back.
A while back I chucked mine up in a collet body with a .75 piece of a steel shaft in it and put it in the lathe and took .250 off of it with a carbide tool. I cant tell any difference in the way it works except that the tts tools touch the spindle nose in the release position.
TTS R8 collet runout
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