Stuck focus ring on RPP 50mm Lens

[John M Rolewicz]

I recently bought some used RPP lenses, and the 50mm arrived with a focus ring that only turns between the near focus and 3ft markers. At near focus, there's a distinct hard stop that feels correct, but as I rotate the ring it gets jammed just before the 3ft marker. When it get's stuck, the aperture ring also ceases up and becomes difficult/impossible to turn. Is this a know issue that sometimes happens to lenses? Could this be caused by dried up grease clogging the mechanism? Or is it a sign of a much more serious problem? I've reached out to the seller about repair and am waiting for a response - so I'm trying to find out what I can expect repair-wise. Thanks!

 

[Scot Yount]

Send it to Duclos?

 

[Alex Lubensky]

Don't try to repair it on your own, likely it's a mechanical issue which of course can be solved (likely). Grease can end up in the lenses, so no grease!

My guess is - something like sand could have trapped into the mechanism, or the lens was dropped and the mechanism got slightly skewed. Usually skewed one can be repaired, which is a little hassle on its own, and sand is a really non-problem as an issue.