Is this mold on the shutter curtain of this Fujica ST801 Camera

Hello all,

 

I just bought a Fujica ST801 on the internet and found suspicious stains on its shutter curtain. Please see the images below. Could someone please offer some insight as to what they are and how I should clean them? The shutter curtain works fine. All the shutter speeds are accurate. Part of the shutter curtain is clean - the part that faces the film when the film advance lever is not cocked (1st curtain). However, once you cock the film advance lever, this dirty messy part of the curtain emerges, the 2nd curtain.

 

There is considerable rust on the camera's interior, so it probably has been stored in a humid environment in the past. Yet I don't smell any musty smell. Could it be mold? It almost looks like some kind of water damage. If it's mold, I'd hesitate to use it because I assume it might contaminate my M42 lenses. What would you suggest as a way to clean it?

 

I am inclined to clean it with q-tips saturated with 91% alcohol. Is that advisable? Would you rather suggest 9% vinegar? I just want to make sure I don't mess up the speeds of the shutter, which is still accurate now, or don't apply something corrosive enough to leave a hole on the curtain. Any experiences you have had with such mechanical shutters would be much appreciated! Thank you guys! - Han

 

 

 

Hi, you might want to read this older thread below:

 

Cleaning the cloth shutter

 

It almost looks like dried adhesive instead. I've cleaned mold spots off the shutter curtains on one or two old cameras (using IPA on a cotton swab, as you suggested) but you'd likely smell it if that's what it was.

Edited January 22, 2018 by m42dave

Dave's thread seems sensible. It could also be a bit of corroded aluminium, if there's a lot in the body, or something left over from previous cleaning. A bit of isopropyl alcohol or dilute ammonia or vinegar on a damp Q tip would likely make it look better; otherwise, if it works, it works; doesn't look like mould to me....

Thank you guys for the replies! If I use vinegar, does it matter what the acidity level of the vinegar is? There are 9% ones and 4.5% ones in store, where I am.

Everything affects something. Vinegar softens and glutenises some proteins. Do we know what the shutter fabric is made of?

Probably not. Main thing is that it doesn't leave a lot of residue when it's dried off, and the proteins seem to settle down. If the shutter was natural rubber on fabric, I probably would avoid using anything but a little water on a Q tip, but its a 70's camera, so that's less likely.

Have you tried just a bit of warm water as above?

I don't think it's likely to contaminate your lenses.

Question and not a suggestion, but would Hydrogen Peroxide have any affect on mold or the shutter cloth? I know Hydrogen Peroxide can be used to clean fungus out of lens and such. Or how about a non-whitening bleach? Just curious.

Everything affects something. Vinegar softens and glutenises some proteins. Do we know what the shutter fabric is made of?

Probably not. Main thing is that it doesn't leave a lot of residue when it's dried off, and the proteins seem to settle down. If the shutter was natural rubber on fabric, I probably would avoid using anything but a little water on a Q tip, but its a 70's camera, so that's less likely.

Have you tried just a bit of warm water as above?

I don't think it's likely to contaminate your lenses.

 

Thank you for your reply James. I haven't tried warm water yet. Waiting to hear all the advices before diving in. I don't know the kind of fabric in this camera. Good to know that my lenses are relatively safe. I'll certainly make sure I use the lenses and camera often, and keep them dry.

I have a Fujica ST801 also, and the curtain material seems quite smooth on mine. My guess is that is is made of rubberized silk, like the Pentax K1000.

I have a Fujica ST801 also, and the curtain material seems quite smooth on mine. My guess is that is is made of rubberized silk, like the Pentax K1000.

 

If it's rubberized silk, given James' warming, I guess I should just try warm water on Q tips for now.

 

If it really is mold, it's probably impossible to eliminate every strain of it and its spores anyways. Since there are so many cracks and crannies inside the camera that the mold and spores could have lodged in already.

Hey, there's mould spores everywhere; relax. Kept dry, they slowly die off, but there's plenty in the air already.

Now the old Pentaxes SV etc had rubberised silk, and often went hard, but the Spotmatics and later seem eminently durable. The K1000 is really just a Spotmatic with a bayonet (well, sort of). I think they must have used a modern artificial rubber on those later curtains. The ST801 is also a late camera, so it's probably OK too.