t.h. cooke speedic lens problem for series c graflex

[jamie young]

I found mostly pristine series C graflex, except the shutter was stuck together from age, and the lens has peeling black paint on the front inside barrel and a very loose front lens element. Every thing else about the lens is good, with working diaphragm, etc. I'd like to get into the front element group and fix this but haven,t had much success. I'm wondering how the front group, the part in front of the diaphragm disassembles. I can unscrew it from the diaphragm and rear element section. I was thinking of making some jigs to try to see if the barrel comes apart more but it would be useful if I knew how it's put together first. Does anyone have experience with this? I did get the shutter curtain taken care of and it's ready to go otherwise
Thanks!

 

[gorbas]

I did take apart TH Cooke Aviar 210mm for cleaning and everything was accessible by screwing out different lens rings. It was not easy, almost all rings were stuck from dust, rust or who knows what. Front filter ring was bent and after my camera tech straightened it out all rings become loose from vibrations. A very nice lens!

 

[shutterfinger]

Check the shutter curtain for pin holes after separating the stuck part. See www.graflex.org/helpboard/viewtopic.php?t=5624 .
I repaired a Series C just over a year ago. I did not have to do more than clean the lens after removing the front and rear lens groups from the main barrel as you have done. The lens barrel is magnesium and frequently cracks or fuses itself to the other parts so having it separate from the main barrel is a good thing. With the front lens group removed from the main barrel look at each end to see if it is internally threaded. The only picture I have of the lens is the front and it does not appear to be threaded and there are no spanner notches either. The front inner ring with the lens info has the gap between M.M. and f2.5 centered at 12o'clock and the word Lens centered at the 6'oclock positions. A large rubber strip that fits the ring only that you can put pressure on can be used to see if the ring will turn. If there are spanner notches or a cap ring on the rear of the front group then at least the rear element is removable by removing it. Also look closely at the outside of the barrel for very small set screws at the retainer ring positions as that was a mounting technique in that era. When removing a ring secured by an external set screw count the number of turns to remove it and reinstall the same number of turns to maintain correct lens cell spacing.

Post some pictures of the lens sections.