Upload & Sell: Off
My 17-55 2.8 IS has developed a particular problem: the MF ring is sticky to the touch. It's tacky, similar to half cured glue. I'm guessing the rubberized coating is breaking down. Oddly the rubber zoom ring is fine. Any home-brew means of "curing" the finish back to a nonstick state?
That might be an uncurable solution. Ha! Get it?
Ok, nevermind. Does it look like it really is breaking down, ie. changed color or appearance? It could have been exposed to something. Unfortunately, there's not a whole lotta surface area you can experiment with. Typically, the problem with older rubber on cheaper lenses is it turns white, and that's an easy solution. And the zoom ring is just fine? Weird.
My first suggestion might seem counter-intuitive, but it could work. That's to try putting something on to "feed" the surface of the rubber, because something is causing it to break down. I'd try something like Armor-All, and applying to a section with a Q-Tip. I've done this with the above scenerio and it's made an old, old Sigma look new, and stopped the white from appearing.
The second is quite a bit scarier - and I have no idea how you would go about applying it - but this is something I'd do if it weren't a lens. That's to try some plain talcum powder. The problem is, I don't see how you could possibly not get it into the workings of the lens. Perhaps again a small paint brush for hobby purposes (not a $120 red sable watercolor brush) could do the trick.
The best solution would be to contact Canon, I bet they'd put a new one on for not a lot of money - especially if the lens isn't particularly old.
Ah - I see you (de)solved it? Good - hope it lasts. You might still try the armor all at some point to help seal it.