score!

[Greg Howald]

A 1937 Bausch & Lomb refractometer. Have downloaded sdpecs and instructions. It is truly dirty and grimey. Any idea how to clean it?

[Dennis]

Greg,
I always used the grocery store 70% isopropyl alcohol
and some glasses Lens cleaners tissues also from grocery store
and need a toothpick or metal tweezers or pick if you could be careful to rub the tissues in tight places.
try to use wood like a tooth pick.
I also don't take things too much apart. Clean without much disassembly, then use it to see if that is needed to be done.

[Greg Howald]

Thanks. I'll try those things

[Sure Squintsalot]

Did you make that rubber powered Fokker?


As for cleaning your scope, I'd use %96 ethanol and cotton rags on anything not transmitting and reflecting light. Isopropyl alcohol always seems to just smear films around. Also, if you're serious about a total dismantling and thorough cleaning, I'd spray thread loosening fluid into all screws, periodically, over a few months. Ancient grease seizes into a fairly stiff polymerized gum that makes screw extraction extremely risky.

[Greg Howald]

I asked Bausch &Lomb for info. They sent me instructions for cleaning their 2024 electronic refractometer. Bummer.