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Replacing Camera Foam

Question
From: K.R.Pallante kpallant@mail.pratt.lib.md.us
Subject: light sealing compounds
Date: 1997-09-09 12:29:37

I have a Mamiya 645-1000s & Universal Press, probably around the same vintage. In both cameras, the light sealing compound that is used around the edges of the film back latches, and in the 645, the prism, are deteriorating into a black tarry substance that rubs off on fingers, etc. Can anything be done about this (outside of a repair shop).

From: Jerry LeDoux ZeissGuy@juno.com
Subject: Response to light sealing compounds
Date: 1997-09-09 14:38:20

I had the same problem with two of my older Contax bodies. Whatever matetial they're using for these gaskets really stinks. I sent the cameras back to Contax and was quoted a flat repair charge of $150.00 each to "bring them back to factory specs." Since they were fine except for the gaskets I had them sent back.

I contacted the parts department and got replacement gaskets for both for under $10.00. It was a project getting the gunk out of the grooves (the parts department recommended alcohol as a solvent, but it's slow work with a q-tip and a wooden toothpick to scrape it out). Some of the replacement gaskets were self-stick and some were not. The parts department recommended using rubber cement as something like super-glue would dissolve the gaskets (and probably make them impossible to remove if it needed to be done again).

I'd contact the parts department of the manufactuere to see if they have pre-cut gasket replacements available. If not, you can obtain the gasket material from Fargo Enterprises (www.fargo-ent.com), a great source for all kinds of camera repair supplies.

It's not a terribly difficult job to replace them, but it's kind of time consuming cleaning out all the gunk. From my own experience, do it or get it done as that gunk can start getting into the workings of the camera. I had it all over the bottom of my ground glass and on my mirror.

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Date: Wed, 21 Jan 1998
From: doregan@ibm.net
Reply-To: doregan@ibm.net

If they ain't broke, leave them alone.

Next time you load a fresh roll of film, leave the lens cap on anf cover the eyepiece and then do a couple of exposures with a bright light shining on the camera back. Try 1/2 second or longer just to really test the seals. If the film is not exposed, you're O.K. for now.

Dennis

Jeffrey S Maurin wrote:

A question for those out there who deal with older cameras:

I was told by a camera salesman that the light seals on my 20+ year old Nikomat should be replaced. He said they would soon begin to degrade and leave black marks on my negatives. He said it would cost about $40 and take 6 weeks (!) to have them replaced.

Questions:

1)How can you tell if they should be replaced?
2)Where should I take/send my camera body to have this done?
(can I do this myself?)
3)How much should this cost?
4)How long should this take? 6 weeks seems like a VERY long time.

Any information/recomendations/suggestions will be greatly appreciated.

Date: Thu, 11 Sep 1997
From: L.S.Davis@exeter.ac.uk
Subject: Medium Format Digest forum Monday/Thursday summary
Original MFD Digest Issue

From: Mark Walberg Walberg@simmons.swmed.edu
Subject: RE: mirror box foam breaking up

Nicolas Eertmans asked about the mirror box foam disintegrating in his FM.

Yes Nicolas, it is very, very common for the foam to be going by this time.

My F2 bodies and FE2 have all needed the foam replaced.

It is simple to do.

Scrape out the old foam.

Clean off whatever is left with lighter fluid or some other solvent.

Glue on a new piece of foam.

Nikon parts will sell you a new piece of foam precut to the right size for 40 cents!

(Isn't it remarkable that keyboards don't have a key for the cent sign?) You can get a bigger piece of foam from several other places, like Fargo (Micro Tools - advertises in Shutterbug), and cut your own. You can get foam sheets (called light baffles) from Fargo that have sticky backs, so you don't even need to use any glue.

Mark Walberg walberg@simmons.swmed.edu

Date: Sun, 17 May 1998
From: Scwywabbit Scwywabbit@aol.com
Subject: [KOML] Light Seals,Baffles?

Looking through the Fargo Enterprises website, I was searching for gasket material for my RO 200 backs. I came up with what they call "Light Baffle Strips". Is this what I want for the backs? If not, please tell me what I should be looking for from Fargo. I found the "Light Baffle Strips" at the following page in their site:

http://www.micro-tools.com/cgi-bin/shop.pl/SID=124320132/page=results.html Thankyou for any helpful info you may provide.

Paul

From Camera Makers Mailing List:
Date: Sun, 27 May 2001
From: Robert Mueller R.Mueller@fz-juelich.de
Subject: [Cameramakers] Replacement Foam

I am sorry to be coming back to this so late but I just returned from a trip abroad and only found the postings on this topic yesterday.

Fist of all, I will let out some venom for the makers of cameras who put this polyurethane foam in their products. This stuff is predestined to turn to paste, damaging the camera in the process. Considering the price of a quality camera and the fact that a good camera SHOULD last for many decades, the manufacturers ought to be forced to repair the damage without cost to the owner of the camera. This foam is like a time bomb in the machine.

It makes no difference what I think, a lot of you have cameras with this paste in them and need a fix. As has been suggested, felt is something to think about, but there are a couple other materials offering a lot of hope.

One is soft leather, like chamois. Generally this will be a little thin if used as a single layer and multiple layers will not be as soft as PU foam; however, consider forming a tube with the seam of the tube glued down, away from the side getting slapped by whatever is falling on the tube. You might even put a bit of something in the tube (see below!). Unfortunately leather also does not offer an infinite lifetime and in time it will get brittle and fail, but the mess will be easier to cleam up than what you have when the PU foam reaches the end of its life.

There is a better longterm outlook for silicone foam (Sounds somewhat like "silly cone", and not to be confused with "silicon", which many persons do, because silicon is a hard element which is brittle and quite useless for this task.) Look for this foam at your DIY shop. I have bought it as a seal for doors and windows. The most convenient form is a long strip about 50 mm wide to be used at the bottom of the door. This is 2 to 3 mm thick and is fastened to the door to keep air from leaking under the door. Its flexibility lets it follow the variation of the floor as the door moves over the floor. There are other shapes offered. Some seal the door around the edge when it is closed. Others are intended for sealing windows. In fact, in a few cases, these other shapes may be better than the flat strip.

My experience is that samples of this foam are in perfect condition after 20 years. The foam has a smooth outer surface with pores inside. This can be useful in applications in which something slides over the foam. The foam would last longer when the pores are not exposed. You can shave the smooth surface away in cases where it does more harm than good. The real problem might be in finding this material. I suggest anyone who locates a source should tell us the brand and source of supply. (I bought mine decades ago and treat it like a treasure. Furthermore, I buy in a market to which most of you have little access, and I have little access to yours so I do not know what you can buy. Sorry!) Another problem is that I have only brown and white. Black would be nice if it can be found. Silicone will absorb some solutions and might let in dye, but will such treatment shorten the life? I have no idea, but brown is probably not all that bad for absorbing light, and better a tight brown seal than a leaky black one or one with a short future.

Good luck.

Dr. Robert Mueller
Institut für Festkörperforschung
email: r.mueller@fz-juelich.de