Leitz Focomat V35 Helical Mount loose

[Dmitri Zorkau]

Helical mount on my Focomat V35 is loose so when I change the aperture I bump the focus out. It is normally secured by a stop but for some reason is loose. How do I make it work?

Regards,
Dmitri

 

[ic-racer]

Small knob #17 holds the focus helicoid in place. Unscrew to fine-focus, after focusing (if lens has rotated), loosen ring #18 in the manual. Rotate the lens to the correct position, then tighten ring #18.

Which one does not hold #17 or #18?

 

[Dmitri Zorkau]

Locking knob doesn't lock it really.

 

[Dmitri Zorkau]

Thanks for your reply. It is helicoidal ring (15) that doesn't hold. It moves every time I change the aperture on the lens. There is no way I can lock the ring. And there is no click stop, it's smooth.