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c/camera-repairersiris574iris57419d agoProlific Poster

A guy at the parts counter told me to soak a stuck helicoid in vinegar

I was fixing an old Pentax lens from 1978 and the focus ring would not budge. He said to soak the whole helicoid in white vinegar for 24 hours to break down the old grease. I tried it on a small part first, and it worked perfectly, no damage to the metal at all. The whole thing came apart clean after that soak. I was worried it would be too harsh, but it saved me from forcing it and stripping the threads. Has anyone else used vinegar on old brass helicoids, or do you stick with a commercial solvent?
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3 Comments
park.abby
park.abby19d ago
Honestly, I would have told you that was a terrible idea. I always figured vinegar was too acidic and would eat at the brass. I've only ever used naptha or lighter fluid on my old lenses. But seeing your results, I guess the mild acid just eats the old grease and not the metal. That's actually really clever. I might try it next time I get a truly frozen one.
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phoenixwalker
Yeah the trick is using white vinegar, not the cleaning kind. That 5% acetic acid is weak enough it won't hurt the brass if you don't let it soak for days. I left mine for about an hour and it turned the old grease into this milky sludge that rinsed right off. Just make sure you give it a good water rinse and dry it fast to avoid any water spots.
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jenny391
jenny39119d ago
Read somewhere that white vinegar works on old brass clock parts too.
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