Festool Quick Ratcheting Clamps - Won't hold.

[Neal W]

I was trying to clamp down some face frame pieces to cut dominoes last night, and one of my ratcheting quick clamps will no longer hold.  The ring will easily slide up the shaft when bumped slightly. 

By this I mean, I clamp the piece to the table top, and as soon as I put the domino on it, the clamp releases. 

Any thoughts or ideas or is this now a paperweight?

 

[RKA]

I think when this topic came up before the solution was to clean the shaft with acetone or something.