Hello Forum,

I have a 4 year old 1100 PCNC that I use for work and love very much except for when I try and machine steel. Today I had a job where I needed to machine some 1144 in a simple, circular pattern (Fusion 360) using a brand new Guhring .50" mill for steel (RF100). I used conservative DOC WOC and used G-wizard's SFM/RPM and the tool still pulled out of the TTS holder! On my first attempt I was using an ER collet holder and the tool pulled out of the collect. On my second attempt with reduced DOC/WOC and a .50 allen screw holder the TTS pulled out of the R8 collect in the Spindle. Fortunately nothing was damaged but I find it very frustrating.

I called Tormach and they called me back later the same day. I had already ordered an New R8 collet today because when I removed my original R8 collet, it had some surface rust on two side, 180 degrees opposite one, another. I have a pneumatic draw bar and I had tightened the draw bar after the first pull out today. There was no rust on the inside of the spindle.

Has anyone else had issues with this? Cutting steel with a Tormach 1100 PCNC? Did you find a solution? Tormach suggested using a narrower mill (.375" or .250") but I would hope you could use a .500" mill, and I need to remove material up to a depth of 1.00" from the stock. I feel a .25 or even .375 mill will not be as rigid?

Any positive, constructive suggestions will be appreciated. Thanks, Cismontguy

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