I used to think tool holders were all the same until I got burned by a cheap ER collet

I ran a job last Tuesday with a brand new 1/2 inch end mill in a cheap collet I picked up on eBay. Everything looked fine on the setup, but about halfway through the cut I started hearing that high pitched chatter sound. Figured it was the speed or depth, so I tweaked the feed and kept going. Then the tool pulled out of the collet completely and destroyed both the part and the holder. That $20 collet cost me about $150 in tooling and scrap material. Now I only buy name brand ER collets from a local supplier and I check the runout with a dial indicator every time. Anyone else had a similar experience with cheap tooling causing a crash?

2 comments

2 Comments

sanchez.blake14d ago

Ugh yeah that high pitched chatter is always the first warning sign. I started torquing my collet nuts to spec and checking runout every time too, makes the cheap holders hold way better.

diana82914d ago

Had the same thing happen with a cheap R8 collet last year. Took a finish pass on a stainless part and the tool just started walking out. Heard that chatter and thought it was tool deflection at first. Checked the collet after the crash and the slots were already mushroomed out from the clamping force. Switched to some actual name brand stuff from a tool truck guy and I can run the same feeds with way less noise. Also started using a torque wrench on the drawbar. Not too tight not too loose. Makes a big difference.