Brian Legge
Veteran
Long story short, my LTM J3 is now missing the shim which sits behind the optics block. I need to find a replacement somewhere. Any help or pointers would be appreciated.
...
I had a J3 which was in good condition but the focus had become too tight to deal with any more. I disassembled the lens and relubed it but found the lube I had on had too thick. I left it disassembled for a few days while waiting on new grease to arrive. Unfortunately some overzealous cleaning was performed around the desk while it was disassembled and the shim disappeared.
I spent the evening going through the garbage cans hoping to find it but no luck.
As I recall, it was a single wider shim and one thin shim. I know these aren't 100% consistent but that would at least be a starting point.
I figured I'd check here to see if anyone had spare parts before hitting up Fedka or others. If you have parts or have recommendations about who might I'd love to get info. Thanks.
...
I had a J3 which was in good condition but the focus had become too tight to deal with any more. I disassembled the lens and relubed it but found the lube I had on had too thick. I left it disassembled for a few days while waiting on new grease to arrive. Unfortunately some overzealous cleaning was performed around the desk while it was disassembled and the shim disappeared.
I spent the evening going through the garbage cans hoping to find it but no luck. As I recall, it was a single wider shim and one thin shim. I know these aren't 100% consistent but that would at least be a starting point.
I figured I'd check here to see if anyone had spare parts before hitting up Fedka or others. If you have parts or have recommendations about who might I'd love to get info. Thanks.
mszargar
Established
Brian,
I don't have spare shims, and I haven't been able to find any. A friend suggested I could use copper tape instead, so, I ordered a roll of copper tape from china on eBay for a mere 2.5 bucks, shipping included. His suggestion seems feasible to me, although I haven't tried it yet...
I don't have spare shims, and I haven't been able to find any. A friend suggested I could use copper tape instead, so, I ordered a roll of copper tape from china on eBay for a mere 2.5 bucks, shipping included. His suggestion seems feasible to me, although I haven't tried it yet...
Brian Legge
Veteran
I hadn't tried copper tape in the past but have tried cutting shims out of material myself in the past. Not as easy as it seems like it ought to be given how low the tolerances are for a good fit.
I actually decided to contact a machine shop and see about having both 0.5mm and 0.1mm shims made*. Not exactly the cheapest solution but I was interested in giving it a shot. I have enough on the way now for doing 2-3 lenses. Hopefully my size measurements are good.
* Unfortunately most places around here deal with material size in inches. So 0.13mm is as small as the shims get. Close enough for my needs though and if I end up within 0.05 mm I can always try something ad hoc to cover the difference.
I actually decided to contact a machine shop and see about having both 0.5mm and 0.1mm shims made*. Not exactly the cheapest solution but I was interested in giving it a shot. I have enough on the way now for doing 2-3 lenses. Hopefully my size measurements are good.
* Unfortunately most places around here deal with material size in inches. So 0.13mm is as small as the shims get. Close enough for my needs though and if I end up within 0.05 mm I can always try something ad hoc to cover the difference.
Dwig
Well-known
Like, perhaps, a layer of paint.