On Friday, our Okuma ATC all of a sudden started chucking tools during the tool change. It seems to be the tool coming out of the spindle that is being thrown. We replaced the arm about a year and a half ago and had everything nicely aligned when we installed the new arm. It has been working just fine since then... until Friday. The first tool it threw was a drill chuck and then it was my $200 finishing endmill. After that, it didn't throw any tools while we were testing it, but we were testing it with smaller empty tool holders. I don't think the root cause is tool size/weight, but I did read that you can slow the tool change down, so I'd like to give this a try for now until I can properly sort it out. The only thing I found in the manual related to that is a machine system parameter called "torque limiter [%]". If I change this, will the arm slow down? Anyone have any experience with this parameter, or have any other suggestions?

We did single-step through a tool change and the arm seems to be gripping the tools very tightly.