Bought a new lens and have a repair question.

I bought another Vivitar 400mm 5.6 on the C/FD mount and the rubber grip on focusing ring is uber loose, Loose to the point where when the adheisive finally breaks under it, it's going to slide right off and the grip on the barrel is bubbling up and will be in the same condition before long.





Does anyone have any suggestions on how to shrink that back down to proper fit?

 

Well....hummmm, I had considered taking a hair dryer to it, but I am not sure if that is advisable for the glass elements inside the lens, additionally I am not sure if it would work as I am sure it's a different material than the shrink wraps I use on car wiring.

Worst case scenario I guess I could get out some of the DS tape from my auto body supplies and refit it. I am kinda hoping to avoid removing it though.

 

If you're going to do that, use a feeler gauge or similar to finish loosening it up, roll it to one end or the other like a condom, and put some adhesive under it before you unroll it back. That way it doesn't get stuck before it's in the right position.

With luck, the tape might be the right thickness to snug it up a bit as well as holding it on.

 

Well, I understand what you are saying here, but I have two types of DS tape in the cabnit, one is paper thin and the other as thick or thicker than the grip is self. I'll likely use the thin tape for the cosmedic accuracy.

This leaves me with two options that I can think of:

1) the "Golf Club trick", whitch is basically similar what you where going at minus the rolling (I'd prefer not to roll it as I have had a couple rip doing that) but with the assistance of mineral spirits to prevent premature adheasion.

or

2) Cut it down the seam and re wrap it right in place snugly and remove the access.


However, both of those have flaws. One it's loose enough that I may not be able to get it all to the tape and the other if it shrinks after it'll rip itself to shreads and be completely toast.

 

Have you thought about building up underneath with dbl sided tape and just putting the rubber grip back over the top of that?

Or taking the ring off and building up the inside with a silicone adhesive?

 

Personally, I would cut it off and replace it with a new piece of rubber (or something similar). I would either glue it on or use double sided tape - depending on how permanent I wanted it to be.

You could just paint some rhino liner on there (that's actually not a bad idea...). There would be no going back after that though...

 

Yeah, the afore mentioned "Golf Club trick", I don't want to build it up though. I have DS tape that would do that on it's own at nearly an 1/8 inch thick. But this would cause the grip to protrude and create an unneccessary snagging edge.

My experience with silicone adhesives has me running as far and as fast as I can away from that idea. Form my experience they are quite soft and have some give to them, I assume this could result in the grip turning on the focusing ring when trying to focus and in cold wether around here the focusing rings can get that stiff to where that would be a problem on a manual focus lens.

*EDIT*

If I had the equipment to spray Rino Liner that would not be a bad Idea actually, I'd have a lot of masking work to do but....

 

Just had another idea-

You could wrap it with some fusion tape. It will look kinda ghetto (if you took your time you could probably make it look half way decent), but it will work and it will be easy to remove later if you wanted to (just cut it off).

 

Hummmm, not my style, but I'll keep it in mind if all else fails.

 

When I do go threw and do this I'll photograph every step of the way for anyone else who gets ambisious enough (anal retentive enough) to want to do this as well.

 

I think the rhino liner would be pretty cool. I would assume that you could buy it in a small quantity (like a pint can or something), but my google-fu is not strong enough...

I don't think you would nessecarily have to spray it. You could probably just brush it on. Mask everything off, of course. I have it on my truck bed, but I've never actually applied it myself. Spraying would probably look better (no brush strokes), but I think you could still make it look good. Do a test piece first.

You might be able to talk someone into spraying it (prep work already done by you) while they're spraying a truck. I think that is certainly the most durable option - you'll never have to fix it again.

I like Mitica's idea of wrapping it in leather too. That would look good.

Whatever you decide to do, make sure you post the results! I plan on keeping my gear for a very long time, so your experience will help down the road. I'm sure others would benefit from it too.