I recently acquired an Agfa Karat 36 which the focusing mechanism was stiff. Disassembled, cleaned, lubed, and reassembled the focusing assembly. Now I need to verify that the rangefinder and lens are in sync. I had made several adjustment to the helical ring till the rangefinder and the distance scale seems to be in sync. Any input is greatly appriciated.
The distance scale can be a convenient reference but it does not tell you whether the subject is in focus. What matters is that the rangefinder agrees with the image in the film plane. A piece of glass or even just a strip of Scotch tape stretched across the film rails can give you a focusing target. Here is a way to check infinity focus (both for the lens and the rangefinder) without going outdoors: