EF600/4L IS collar sticking

[Frank Kolwicz]

The rotating collar on my 600 no longer moves smoothly and it's a bit of a pain as I use it frequently. Does anyone know how to lubricate it or otherwise fix it? It suddenly changed when the weather got wet a couple of weeks ago, it was fine all summer.

The collar, of course, is not easily removable.

[Bob Atkins]

As far as I know there's no way to get that collar off without taking the lens apart. I guess what I'd try would be something like a few drops of WD-40. It's a water displacing lubricant and also acts as a decent solvent. I'd try a few drops followed by lots of rotations of the collar.

Do this at your own risk of course. I don't think there's any route from the rotating collar to the inside of the lens but I've never taken a 600/4L apart. You certainly don't want to get any volatile oil inside the lens.

You could also try calling Canon tech support for their advice, but my guess is all they will do is suggest that you send it in for them to take a look at, which with a 600/4L is a rather expensive proposition with shipping and insurance costs, not to mention their fee if they actually do anything.

[Frank Kolwicz]

Thanks, Bob,

Somewhere I have a Canon schematic of the parts for this lens, so I should be able to tell if there's any possibility of internal contamination.

I'm a bit leery of WD-40 as it is also a penetrant and there is a joint not far from the collar. What I may resort to is some lock lube that's in a tube with a needle applicator so I can easily apply a drop at a time.

It's a pity Canon didn't make the collar easily removable, I bet there just some minor dust in there that got wet with the return of normal Oregon weather and gummed-up a bit.

[Frank Kolwicz]

A very small amount of lock lubricant, applied with it's needle point tube, on each side of the collar where it joins the lens body did the trick. Now, I hope it doesn't pick up a lot of dust and make it worse.