Spent 3 hours cleaning a shutter curtain with lighter fluid and it melted the edge right off

Was working on an old Pentax Spotmatic from the 70s, you know the ones with the cloth curtains. Read online that lighter fluid was safe for cleaning off that sticky residue. Tested a tiny corner first and it seemed fine. So I go ahead and soak a Q-tip, clean the whole curtain. Looked great. Come back 10 minutes later and the edge where I started is literally dissolving and curling up. Never again. What do you guys actually use for stubborn gunk on cloth shutters without wrecking them?

2 comments

2 Comments

emma_smith15d agoMost Upvoted

Honestly I think people get lighter fluid mixed up with naptha. Lighter fluid is actually a mix of things and some brands have additives that eat rubber and cloth. Naptha is the pure stuff that's generally safe. I'd stick to plain old 90% isopropyl alcohol for cloth curtains, apply it with a dry Q-tip that's barely damp, not soaking wet. Let it sit for a minute then blot it dry right away. Never soak anything on a cloth shutter, that's how you melt the glue holding the curtain together.

singh.blair15d ago

My 1975 Yashica-Mat 124G has a cloth shutter that I nearly wrecked last year with lighter fluid. Took me forever to find out that the Zippo brand stuff had some weird additive that left a sticky residue. @emma_smith is dead right about the naptha being safer, but honestly I've been using 91% isopropyl for years on old cameras with no issues. The key is what she said about not soaking the cloth, I learned that one the hard way when a shutter curtain started peeling at the edges. Do you think the alcohol trick works on bellows material too or is that a different beast entirely?