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View Full Version : Re-Cementing a Lens: Anyone want to help?



Frank R
22-Jan-2010, 08:31
I have an old brass lens that has to be re-cemented because the balsam is crazed.

I have heard it was easy if you buy the right glue; I just don't have the time. I am looking for someone to do it for me.

If you have successfully glued a lens together and want to make a little money, please email me with a quote of how much you would charge.

I will mail the lens to you and you can use the same box to mail it back.

John Schneider
22-Jan-2010, 09:28
It is never easy or simple. That's why someplace like Focal Point charges $2-300 for even straightforward recementing jobs.

Steven Tribe
22-Jan-2010, 10:22
This winter I am "redoing" two rapid rectilinear/aplanats. The big problem is getting the lens out of its mount. There is no one way they did this - it is rarely just screw threads. Some are difficult and imply a degree of risk. A few were never meant to be taken out of the mount and were planned to be exchanged for newer optics in 1910! These can often be remounted after repair but with modern silcone materials to hold them in place. I can understand the fee. If you can get the lens successfully free - it really is easy. Having lenses of a certain size (say more than 30mm) helps.

Put the lens in a sealed container with Zylol/Zylene and wait two weeks (approx.).
Clean and Dry the surfaces. Then reglue it. Harden/cure using heat or UV (balsam/synthetic)

The first step takes 2 weeks - the second takes an hour if you have the material present. I taking photos this winter for documentation later here - is there is interest.

Doing a two lens glue is pretty easy for the beginner even with two components that have different radii. Problems arrive with 3, 4 and 5. I have heard it said that Gundlach couldn't assemble all their 5 element Turner-Reich consistently at the factory!
I am sure there is someone here who can help you but perhaps you could describe the lens type, mount etc.

Glenn Thoreson
25-Jan-2010, 12:15
I've done a few occasinally. I soak them apart in lacquer thinner. It takes a few days and they'll finally just slide apart. I have a method of marking the edges so they go back together in the same position. The right UV cure optical cement can be pretty easy to work with. It's unforgiving stuff, though, so you do not want to make a mistake. Some lens cells are mounted in the barrel by rolling the brass over the edges of the brass. They can be a real pain to get them out and, worse, to put them back. I'll leave you a private message.