Model Airplane Dope for Covering Repairs?

A while back I acquired a nice Mamiya 6 V with the Olympus D.Zuiko 75mm f3.5 lens. Other than being a bit dusty the camera was in quite good condition. The only blemish I found was a scuffing of the covering on the lens cover and a lifting of a couple of corners of the covering on the front of the camera. The scuff lifted the top layer of the covering, leaving a flap of fiberous material that looked like some sort of paper product rather than leather or leatherette. Were these cameras covered with a paper material that had a glossy embossed top layer?

Since it appeared to be paper, I hit upon the idea of using model airplane dope to re-cement the loose flap and to cover and seal the blemish. I bought some clear butyrate dope and thinner and made up a small batch and brushed it onto the covering at the scuff and, voila! It re-cemented the covering and sealed the loose flap quite nicely. I also used the clear dope to re-cement the lifting corners of the covering and it worked wonderfully!

This worked so well on the Mamiya that I also used some black butyrate dope to cover a blemish on the lens cover of an Ansco Speedex recently purchased at the online auction site. Something had been spilled on the camera box and had leaked through onto the lens cover and basically dissolved the plastic coating on the covering material. The fabric weave was showing through and looked quite unsightly. I used the black model airplane butyrate dope to paint over the blemish and it covered it well. A couple more coats and it the blemish should be almost invisible.

Great timing on your post. Last night I started cleaning up an early post-war Mamiya Six (IV). Lens marked Zuiko 1:3.5 f=7.5cm Takatiho Tokyo.

Body covering is complete but is lifting a bit on the lens door and last night the covering on the camera back almost completely detached in one piece. I think originally they would have been glued with shellac. If I used the butyrate dope could I use the thinner as a solvent to remove the covering if necessary at a later time? I wouldn't want to use something like contact or rubber cement as it could prove difficult if later repairs required removal of the covers. Your repair looks very tidy. Apart from cleaning, are you applying any sort of preservative to the covering on your cameras? I was thinking of one of the low sheen auto products like Aero 303 or one from Mothers / Meguirs. (Definitely not Armorall).

Looking through the viewfinder of my example was total 'whiteout' conditions. I have removed the top plate and cleaned the viewfinder and rangefinder windows, all good. I have removed the rangefinder and I only intend to clean the lenses. The partial mirror looks good. With minimal disassembly I should be able to clean the rangefinder lenses in place. (Complete disassembly of the rangefinder requires the lenses to be re-glued with shellac in precise position. I don't want to go there.)

A tip for cleaning the tiny, round windows for viewfinder / rangefinder. I get a PEC pad and roll it around a bamboo skewer and secure with tape. This gives me a tube of PEC pad about 3/8" inch wide. Make one for wet and another for dry. With drop of cleaning fluid on one end it is easy to use the tube 'brush' to clean right up to the edges of those small round windows. After each window slide the PEC pad up the skewer and trim off with scissors and you have a fresh piece of brush for the next surface to be cleaned. The PEC pad is very gentle and I'm getting excellent results.

I still have to clean the taking lens on mine. A little hazy but no fungus and I'm hopeful of a good result. Lens / shutter assembly has to come out as the slow speeds are definitely slow. Hopefully a minimal flush with naptha will improve this.

Otherwise, mechanically, everything operates very smoothly. I think that Mamiya chose their lubricants well. No sign of the solidified grease that afflicts some German cameras of the period - AGFA as a prime example.

In my model airplane building days, I painted the outside edges of the balsa frame with dope, let it dry, then laid on the tissue or silkspan covering and brushed fresh dope on top where it met the framework. This technique would soften the dope on the framework and bond the covering to the structure. So, I'm guessing that if you do use the dope as a cement, then using thinner later on by working it under an edge would soften the dried dope and allow lifting the covering. I think it would be a time consuming affair though as you would have to work from the edges inward. There wasn't enough loose covering on my camera for me to lift and examine it closely - I still think it is something besides leather.

On this camera I used a very small amount of Propert's All Purpose Cleaner and Conditioner on a microfiber cloth to clean the covering on my Mamiya 6. The bottle says it's a Kiwi Brands product made for cleaning leathers, imitation leathers, and plastics. I've had my bottle for ages and it's almost gone, but I can't find where it's still available. I would think any high quality wax product, like carnuaba would be a good protectant for this camera's covering. Thanks for the tip on the PEC pads.

Yes, the mechanics and the optics on my example are in quite good condition. The only problem that I've seen is that the rangefinder is a hair off vertically, but appears to be quite accurate otherwise. I can live with that.

I feel that model aircraft 'dope' may not be any good. (Amyl Acetate) It drys too quickly and that is where the problem is, it becomes brittle and will flake off non absobant surfaces such as a camera body. By far the best adhesive is something like a contact adhesive where you coat two surfaces, let it dry and bring the two surfaces to be stuck together ar once. The disadvantage of this is you only get one chance so it has to be accurate.

When I was repairing cameras to make a buck we used Pliobond which is
a contact cement BUT only one surface was glued. Both surfaces & it was permanent.

Yes please, as John said use Pliobond or another good contact cement. Glue one surface and press together wet. It will hold the covering well and can still be removed in the future, if needed. I'm not sure how airplane dope would be coming off but I'm pretty sure the leatherette will be ruined. When working on and restoring old cameras its not uncommon to really need that old covering. Plus, contact cement is much easier to work with.

I have heard a lot about Pliobond. I get the impression that it is a flexible contact adhesive. We have similar glues in Oz. I think that I will go this route rather than butyrate or shellac. Just a thin bead around the edges, on one surface, and then press closed and hold with rubber bands as required.

I'll start a new thread with my on going refurbishment efforts on this camera. Suffice to say that I managed to successfully clean all of the surfaces I could get to on the rangefinder mechanism with the exception of the inner surface of the exit pupil lens which faces the viewfinder. This lens is cemented in place just behind the partially silvered mirror. Viewfinder and rangefinder patch is usable but not brilliant. Taking lens is now to be tackled.

tokam said:

I have heard a lot about Pliobond. I get the impression that it is a flexible contact adhesive. We have similar glues in Oz. I think that I will go this route rather than butyrate or shellac. Just a thin bead around the edges, on one surface, and then press closed and hold with rubber bands as required.

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I don't think a thin bead around the edge will be enough. The normal way is to just spread a thin coat on one of the surfaces in its entirety and carefully lay the leather down where it goes. You need enough glue for it to stay wet while you work, but not too much, you want the leather to be flat and tight looking once the glue dries. I usually spread the glue on the covering, some people prefer to spread it on the camera itself, either is fine, whichever seems best for your situation. I've never needed any rubber bands or tape or anything either. The proper amount of glue will dry pretty quickly and just pressing the leather in place with your fingers or a flat tool should do the trick. Excess that seeps from the edges is easy to clean. A little naphtha solvent (white gas, lighter fluid) on a clean rag will wipe it off.

Thanks for that, El Dorado. I can't see any further disassembly would be required on the camera back so I will glue it down properly. I'll check first that naptha is suitable cleanup solvent for the glue I will use.

Dope is lacquer.

no harm if you use lacquer with leather or paper, but not sure how leatherette will react with it... may melt it.


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