[gumenjak]

Hi, can anyone help me to assemble focus ring on Yashica Yashinon-ds 50mm f1.9? I open it to clean fungus, and i did it very well but now cant return that piece on photos on place. Any suggestion would be nice, thank you

Attached Images

         

[Just1MoreDave]

General advice: The larger steep-pitched threads that focus the lens have several starting points. You can count the points where the threads run out when the lens is apart. Often it's three starting points, 120 degrees apart. Usually only one starting point will work, that is, all the other parts end up in the right place at the right time. You'll need some trial and error to figure it out. First count the points, so you'll know how to adjust when your first try doesn't work. Mark the parts somehow so you know where you started. Then make an attempt. If it doesn't work, unscrew the large threads carefully so you can tell exactly when they separate. Then rotate the front group 120 degrees or whatever and engage the next set of threads. It's like Rubik's Cube - some observation of all the moving parts helps figure it out. Sorry I can't give specific advice for your particular lens.

[simple1]

Based on the 3rd picture you have the outer helicoid ring out way too far. For that lens a good starting point would be to turn it until it is about 4mm off the base. Then adjust a little to get the sliders aligned with the inner helicoid/element assembly.

[gumenjak]

Thank you all. I did it after 3 days of trying