[Spinnetti]

There is a Tormach tech support document on toolholder/collet slippage here:

Product Documents | Tormach LLC | We provide personal small CNC machines, CNC tooling, and many more CNC items - ER Collets and Tool Holders

which basically says the same thing that Ray did.

I've had the same problem until following those gudelines.

BTW, are you using Tormach TTS holders or another brand?

Mike

Thanks, I did read that, and followed those guidelines. Its a brand new Tormach PCNC1100, and holders.