Canon 500mm F/4 IS - Tripod Collar Sticking

This is a follow up on a recent post, and could be of some importance to anyone with a Canon 500mm Lens.

My last post was that the tripod collar had become tight, and was not smooth to swivel. One comment was that this had happened to another user, and he had the tripod collar replaced at Canon for $380.

I had also posted this message on another forum, but I had thought that I would just send the lens to Canon and wait two or three weeks to get it fixed. To my surprise there was a message waiting for me at the other forum from someone with a sticky tripod collar on a used lens that they had just purchased. I forgot to check back thinking I should just send the lens in.

The person told me that they had just bought a replacement foot for the lens, and upon removing the original foot a screw fell out and a washer. I thought I had nothing to lose and removed the foot from the tripod collar. Well wouldn’t you know that a screw fell out, and as I turned the collar the washer fell out.

All three screws inside the collar were loose plus the one that fell out, and after replacing the screw and tightening the rest the collar works like new.

I thought that this would be important to anyone that has their collar tighten up on them.
The screws are very small, and I am wondering if I should have put some lock tight on them.

Cheers
Mike Veltri