Sticky Tool Holder Syndrome

Cleaning, maintenance and adjustment ideas to stop tool holders from sticking during CNC operation. February 13, 2009

In one of our machines, an Andi Exxact 51 with ISO30 toolholders, the tool holders will stick in the router (using the tool changer); it seems to happen on old and new holders. This happens once or twice a day. We keep them clean as well as the router. I'm thinking of using a dry lube to keep them from sticking. We modified our post so that the tools are always removed from the router at the end of each program so they stay as cool as possible but that did not do anything. Does anyone have any suggestions?

Forum Responses
(CNC Forum)
From Brian Personett, forum technical advisor:
Try a little TFE on the ISO cones.

From contributor R:
If the toolholders and the cone inside the spindle are both clean and undamaged, then you want to look at the draw bar. These are "fingers" inside the spindle that pull the stud on top of the cone. Be very sure that the air pressure is right, and that you have the right studs on your toolholders. (Different ones might look alike). Otherwise, you might be looking at a spindle repair.

From contributor B:
I've solved this occasional problem with a number of procedures. Primarily, we have a daily tool holder cleaning routine. Then we also have a monthly spindle taper cleaning, and more often if we are having sticking problems. I've also applied grease to the tool holder studs and seen some relieving of the problem. I've also applied anti-seize compound to the spindle taper to help the problem. However, the cleaning routines have pretty much eliminated this as an issue in our shop.

From contributor M:
You should never run your machine unless there is a tool in the router. In other words make sure there is a tool in the router when using the drill block. Also the spray you should use is primarily used for the HSK tool holders, but you can use it on the ISO30 cones as well. Do not use anything else but Lusin G31.

From the original questioner:
We go a couple of cans of TFE based spray from Grangers. I haven't heard of any issues yet. The tool release system work fine as we can test that manually. We clean the tool holders at least once a day and never run without a tool in the router. I'll look into the Lustin product. What makes that special for this use?

From contributor M:
The G31 spray is a dry spray designed where metal to metal contact is an issue. When applied to the cone you will feel an immediate difference. No longer will it "pop" out, it will fall out. I would never use anything else on ISO 30 or HSK tool holders. You will probably save money over what you are using now. Contributor R also brought up a good point on the draw bar. You can also look at the tip of the cone. This part should still be a black color with no shine to any part of it. If you see any shine in particular to the radiused underside then the locking mechanism is coming apart. Please do not try to save money and do the job yourself. I promise you will spend more money doing it yourself. The only thing you might want to do is pull the motor off and send it to get fixed.