I recently acquired a Beau Brownie. Everything seems functional, except the lenses are pretty dirty and there is some fungal damage for sure. I've let it cook in the sun for a couple of days to get rid of any living fungus, but I'm hoping to get it as clear as possible.
- I've heard alcohol can damage the lenses, is this true?
- Should I attempt to dislodge the nails to disassemble it?
This page on how to clean a Beau Brownie, as well as looking at a version in person, makes it appear as though there is no way to access the interior of the lens/shutter without removing the nails. Alcohol will not damage the glass at all, the lens is uncoated and pretty durable. I usually have better luck with starting off with hydrogen peroxide to remove fungus and then moving to a lens cleaner for final cleaning of whatever residue is left over. Avoid cleaning the mirrors inside the viewfinders with any liquid (a blower is fine), the reflective coating on them is usually pretty fragile. I wouldn't think alcohol would damage the enamel surfaces of the camera, but perhaps starting with water would be better just in case.