An old timer told me to never trust a worn collet, even if it looks fine

Back when I first started running a Haas VF-2, a guy named Ray who'd been in the shop for 20 years pulled me aside. He said, 'Kid, if you get chatter or a tool pulls, check the collet first. Don't just blame the speeds or the tool.' I thought he was being overly cautious. About six months later, I was running a batch of 304 stainless parts and getting a terrible finish. I messed with the feed, the RPM, everything. Finally, I swapped out the collet for a new one, even though the old one looked clean. The chatter vanished completely. Ray just nodded from across the shop. Now I keep a log and replace them on a schedule. How do you guys track collet wear on your machines?

3 comments

3 Comments

jennyh557d ago

You log collet changes? That seems like a lot of extra work. I just check the grip with a pull test every few months. If it holds, I run it. Has that ever actually failed you?

king.aaron6d ago

Yeah, I saw a post from a guy who had a tool slip because the collet wore out in a way a pull test didn't catch. It was holding fine for the pull, but under real cutting forces it let go and wrecked the part. @jennyh55, that's why I started logging. It's not about the pull test failing right then, it's about tracking wear over time before it gets to that point. For me, noting the date and hours run is just a quick note, way cheaper than a ruined piece of material.

cole_patel414d ago

Ever had a pull test pass but the tool still slipped?

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