A drop of lighter fluid on a stuck focus ring finally freed it after 3 days of soaking in oil
Had an old 50mm lens come in with a focus ring locked up solid, so I did the usual thing and let it sit in penetrating oil for a few days, which did nothing except make a mess. An older repair guy down in Tucson mentioned he'd had luck with a tiny bit of lighter fluid worked into the gap to break up old grease, and it cracked loose in about ten minutes. Has anyone here found a solvent that works better without eating the paint off the barrel?