Copal #0 shutter slow speeds

[loccdor]

I have a Copal #0 originally from a Polaroid 110A Land Camera 127mm f/4.7. Speeds 1/15-1/300 seem good but 1-1/8 just cause the shutter to stick open. I don't really see grease on the blades. Bulb mode works fine. Cable release and standard release both have the same behavior.

Anyone know what causes this abrupt cutoff of the slow speeds?

 

[Kino]

Speculating that it is probably an escapement gear train that engages at the 1/8 shutter speed level that needs to be cleaned and lubed.

How one does that on this particular shutter, I do not know.

Maybe this will help:

Prontor SV, SVS, and Pronto Shutter Repair Manual

Factory service manual

learncamerarepair.com

 

[loccdor]

@Kino Thank you!

 

[retina_restoration]

The slow gear train is dirty/greasy.

 

[loccdor]

The slow gear train is dirty/greasy.

Thanks! I think I'll try opening it up and cleaning/lubing that area while disassembling as little as possible. I saw that the old Retina Rescue site has a PDF manual and am also looking at a couple videos.

 

[RalphLambrecht]

I have a Copal #0 originally from a Polaroid 110A Land Camera 127mm f/4.7. Speeds 1/15-1/300 seem good but 1-1/8 just cause the shutter to stick open. I don't really see grease on the blades. Bulb mode works fine. Cable release and standard release both have the same behavior.

Anyone know what causes this abrupt cutoff of the slow speeds?

View attachment 415837View attachment 415839View attachment 415838

correct. this is caused by hardening grease due to age or lack of use and only a clean and relube will help.

 

[Dan Fromm]

OP, Copal <>Prontor.

#0 is a size standard. There are Compur, Prontor and Copal brand shutters made to the #0 standard.

You have a #0 Prontor SVS. Repair instructions here: https://archive.org/details/prontor-s-sv-svs-1/001_pdfsam_prontor/

 

[loccdor]

I was able to lube it and get it fully working with a few hours effort! It wasn't very dirty inside, but it was dry as a bone.