Another adventure in M84 cleaning

[jmcjr]

Well picked up another scope with what turned out to be some crap on the reticle glass. Took about 2 minutes to clean it with some alcohol and a Q-tip. The most touchy part is disassembly, I have a high quality optics spanner wrench which fits the objective lens locking rings as well as the window. Care must be taken to not muscle the components, steady pressure overcomes the sealant. Count the turns of the objective assembly to return the objective lens to proper focus. If you forget to count, leave the locking ring off and sight in on a distant object...200yards or so, preferably a known distance, turn the objective lens carefully until in focus. Once in focus, install the objective assembly locking ring and window. I put a very small dot of clear nail polish to fix the objective lens assmebly since I have no sealant. If you decide to clean a scope, use no force, guerilla hands will cause damage. By the way, I have successfully shot my M1D with the scope.

[oldtirediron]

well, the M84 scopes were all assembled with asphalatum as a water proofing compound, Yes that is the black stuff that flakes off and fouls the optics. Should you start to dis assemble the scope and find that the lock rings won't move, all you need is a hair dryer or a candle. You can heat the metal tube where the lock ring is with a hair dryer and it should liquefy the asphalatum to a point where it releases, if not use a candle and heat the outside of the scope until it is warm, do not heat the lenses!! They will crack or shatter !! This method also works for the M-2 compass, and a lot of other Pre 1955 optics !!