I would rather recommend you not to follow this suggestion unless you want to completely f*** up your
Originally Posted by darkosaric
I have repaired several Agfa folders with frozen helicals and heat has always worked for me.
First, take off the outer ring with the distance markings (three little set screws). Mark infinity position with
a pencil on the black painted part close to the front element.
Then carefully heat the lens/shutter unit with a hair dryer for several minutes. Take it easy, don't get carried away, the focus ring
should be hot too touch, but you should not burn your fingers. From time to time, put the dryer away and
try to move the helical with your bare hands. Use a piece rubber as a friction tool. I don't recommend
to use a pair of pliers or similar, as you might damage the element or the threads by compressing thbrute force.
It may take some time, but eventually the front element will unscrew.
Mark the place where threads start to come apart and use the same position when reassembling.
You can then clean the old lube out with a cotton bud/swab and your favorite solvent.
Iso-propanol works well for me. Be careful and make sure you get nothing of the old glue/solvent on the glass, as you probably will not be able to remove
it from there without damaging the coatings which are very soft. If you don't have access to professional helical lube
you can use vaseline to relube the helical after you have cleaned out the old stuff.