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Post: 425 (12 liked)
Join date: July 2016
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on Dec 14, 2021 23:20:15 GMT
Last Edit: Dec 14, 2021 23:21:27 GMT by lenslover
Greetings Everyone,
i've two 167mt Contax sitting here, one i discovered accidently into a Box, whereas i've bought it some ~5 years ago "for spare parts", and just put into new batteries, and it was working fine, i released the shutter some 15-20x, and each one was perfectly, like nothing happened. It does include the P-5 batteryholder, too. The other one...not so good, i remembered i bought it last year, as working condition, and put it back somewhere..you know, whileas it was cheap. It turned out, one of the battery contacts (AAA) the top right side is somehow being corroded, oxidized, it does have a blue-greenish tint like over it.I put fresh batteries inside - and guess what, nothing happened.
May this being repairable, or is it gone for good, sadly?
thanks for your help.
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Group: Administrator
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Join date: February 2017
Status: Failed treatment for L.B.A. and G.A.S,
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on Dec 15, 2021 2:50:47 GMT
Posted: Dec 15, 2021 2:50:47 GMT
I've managed to clean the contacts on 167's and that was enough to revive them -but- the corrosion wasn't bad enough that it wicked up the wiring to eat it away. If the chrome plating is gone, then you might need to add something to make up the difference in depth. Maybe losing as little as 0.1 mm would be enough to cause too big a gap for the battery to reach the terminal and get proper electrical contact.
If the corrosion is really bad and it did eat the wiring, then it would mean replacing that lower piece from a donor body and/or resoldering it with a new wire.
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Group: Moderator
Post: 1,925 (524 liked)
Join date: April 2014
Status: Long, long time Contax and Yashica user; glad to be here and hope to contribute.
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on Dec 15, 2021 11:48:08 GMT
Last Edit: Dec 15, 2021 11:49:00 GMT by biggles3
As lumiworx has said, if the corrosion has reached beyond the terminal, it is a more complex process. But if only the terminal is corroded, the fix can be very simple... I always have a supply of two items handy: deoxIT for removing battery and general corrosion on electrical contacts (vinegar or lemon juice will also work - use baking soda for any remaining residue and then wipe and let dry) and Electrical Conductive Paint (I prefer the silver-based type) to re-cover the damaged terminal. This combination has revived dozens of cameras that were described as 'junk' or 'for spares' due to battery corrosion where that damage has been confined to the battery compartment.
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Group: Member
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Join date: July 2016
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on Dec 15, 2021 19:22:03 GMT
Last Edit: Dec 15, 2021 19:25:02 GMT by lenslover
Thank you both, i haven't opened up the body, i don't know, if there are further defects, or like biggles said, like the interal wire being eaten up via corrosion..somehow, the sisters came into my mind..."sing this corrosion to me...hey now.." So just putting baking soda into water, and clean the contacts with that? Not using 99% isopropanol alcohol? This 167mt was being described as fully working, sadly. I never checked it out, since my original 167mt, the first one, is being here & there into usage since 96. These two others, i just bought years ago, because the deal was too good on ebay.
And i missed the Auction end today some time ago earlier, a mint-like Contax ST, in box, but with useless Zeiss Jena 50/2.8 Tessar M42...which is way boring. CZJ produced literally millions over decades from this slow F2.8 50mm...it was gone for >250 EUR, and i bid a bit less than 200 EUR..the ST was into short just an updated 167mt.
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