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Repairing Light Seals

We have all opened the back of a vintage camera "find" only to discover the old door seals are either so dry and flaky they raise dust, or so gummy they look like tar. Chances are, if the door seals look this bad the mirror damper is also in need of restoration. It is one of the repairs you most often need to consider on a vintage camera and, regardless of how daunting it might seem if you have never done it, it is one of the easiest repairs you can make.

Reader Jon Goodman has a marvelous, inexpensive repair kit (see below) available for this restoration, and was kind enough to share these photos of how it works.

(a)   (b)   (c)   (d)       Follow this sequence, from left to right.

Mirror Damper or Mirror Brake
The sequence above shows a dry, deteriorated mirror damper (a). The first step in the restoration is obvious: remove the old foam! An Exacto blade is a good tool to begin with. Remove the old foam strip (b), being careful to minimize any pieces falling into the body of the camera. You are going to have to remove them, if they do, so caution here really pays off. Once the base is clear, use a pair of tweezers to gently place (c) a new piece of self-adhesive foam (I'm going to tell you in a minute where to get it) on the spot you just cleaned. Once you are certain it is positioned where you want it, gently press the foam down to make the adhesive seal (d). You're done with he first part! I told you it was easy!

(a)   (b)   (c)   (d)       Follow this sequence, from left to right.

Door Seals
Door seals are almost as easy. First, (above) clean out the worst of the black goo the old seal material has turned into (a). Next, use a bit of cloth or paper towel and solvent (I use regular rubbing alcohol) to remove the remainder of the old residue (b). When it is clean, press the new sealing material into the slot (c), trimming at the end and avoiding the frame counter reset pin. The slot (d) is now sealed perfectly so there will be no light leak!

The hinge seal before (left) and after (right).
Repeat the process at the hinge end of the camera door (above).

Before (left), a clean latch end (center), new seal applied (right).
And again at the latch end (above).

Hinge and door seals before (left) and after (right).
And finally at the outside edge of the rear door itself (above). That's it! Now you're really done!

Jon Goodman
Jon is one of the Gentle Readers of this site, and he generously provided the pictures for this section. He has a great, inexpensive product and tool available for resealing vintage cameras. His web site is still in development, but you can find his eBay auctions by looking for the seller interslice. You can also email him with a request for more information. Just put Mamiya Light Seals into the subject line, so Jon knows it came from here!

You can also get pre-packed restoration material from Micro-Tools, a good source for a lot of camera restoration materials and tools.

Other do-it-yourself repair sections are listed below (note - line items in blue are live page links; items in black are still under construction):

If you would like a specific repair or instructional item to be considered on this site, simply go to my Mamiya 35mm Forum! and make your suggestion known. I will add it to the list of things to do. However, please don't hold your breath, because it is likely to be some time before I can get around to documenting all the things that might need explanations, and I would hate to be responsible for even small portions of the camera-collecting population turning blue! Also, because mechanical and technical skills vary widely from person to person, no liability for results or damage is either expressed or implied in the use of these notations.
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