I’ve given my 1953 Leica IIIf “red dial” a CLA, or Clean Lube and Adjust and now I need to replace the half-mirror, or beamsplitter in the rangefinder. The beamsplitter gives the double image that moves back and forth as you focus the lens until the two images become one, then it is focused. On older cameras, the beamsplitter, which is a half-mirror, or partially silvered so it is transparent as well as reflective, looses some it’s reflectiveness and is hard to focus.
After getting the top off (see the procedure here) I was able to get to the rangefinder.
After I got the beamsplitter housing bracket loose, I noticed there were two objects in the way to prevent it from sliding out…
Now the beamsplitter housing can slip out
I got my beamsplitter pre-cut from a fellow on eBay (nobbysparrow) and it was only $10. I say only because it is way worth it, not buying some stock and trying to cut it myself. let alone send it off to have it professionally done for around $110 or more.
Plus it is a modern process (the silvering) from Japan and less likely to rub off and fade through time.
It really isn’t hard to do this yourself. follow my instructions on how to remove the top plate and you can have a new fresh beamsplitter in your Leica for a fraction of the cost and a few hours, not weeks or months