Lens Replacement

I have a reproduction brass rifle telescope.
4x15 power.
The ocular lens is cloudy and needs to be reground, polished or replaced.

Who can do the work or repair/refit the existing lens?

I have removed the lens but cannot tell if its glass and the balsam is hazy or if its plastic and can be replicated re-polished etc.

Because I'm not educated on the topic in the very least is this something an ordinary optics lab can tackle or would the project require a specialized technician and have to posses the front lens as well to craft the rear up to a workable solution?

The lens is 21.7 mm in diameter and is convex on the rear with what looks like a very slight elliptical shape of the front or internal side or as best I can tell.

Because the tube and rudimentary mounts are in very good shape I would like to bring it back into shape so it can be used.

Does anyone know what can be done?

State side the only guy I know that "might" is here:
https://ironsightinc.com/index.php?route=information/information&information_id=4

If it can be shipped to Canada, Warren might give it a go. I'll email him an ask.

303_enfield said:

State side the only guy I know that "might" is here:
https://ironsightinc.com/index.php?route=information/information&information_id=4

If it can be shipped to Canada, Warren might give it a go. I'll email him an ask.

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303 thanks!

Having the lens in hand I was hoping someone would say it could be taken to an optician or lens maker that could analyze it and then if the need be replicate it if that could be done.
For all I know it may just need to be re-coated or something to get it cleared up.
Theirs no obvious damage like scratches chips or apparent damage to it other than an opaque haze that causes a distraction when looking through it.

This guy on eBay, somewhere along the line I had contact with him and if I remember correct, he does the type of work you are looking to get done.
Worth an email anyway.
A few years ago ironsite fixed a Redfield for me and it was estimated to take well over a year. It was done on time though, still over a year.

jbrown40004

go to eBay and do a members search, he's still an active member. From there you'll be able to contact him although eBay might block any contact information.
Good Luck.

List of scope repair places

Actually its hard navigating eBay so I googled the guys user name and his name popped up on several forums. The link below was one of them with a list of other guys. Parson's is another guy that does scope repair.

www.parsonsscopeservice.com

http://forums.thecmp.org/archive/index.php/t-221787.html

pre64hunter said:

Actually its hard navigating eBay so I googled the guys user name and his name popped up on several forums. The link below was one of them with a list of other guys. Parson's is another guy that does scope repair.


http://forums.thecmp.org/archive/index.php/t-221787.html

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Thanks for the tip Ill check it out!

Please let me know what you find out. I have and old red field and another old optic that the rear lense looks hazy but these optics look perfect on 60s and 70s rifles.

I am a certified idiot about optical lenses, but I studied up on restoring old telescopes once. Often these lenses are made in two pieces and glued together. Does it look like maybe the lens itself is ok, and it is the adhesive that has clouded? Just thinking that might be a much simpler fix, but no idea how to go about it. Just a thought.

Johnny5k said:

I am a certified idiot about optical lenses, but I studied up on restoring old telescopes once. Often these lenses are made in two pieces and glued together. Does it look like maybe the lens itself is ok, and it is the adhesive that has clouded? Just thinking that might be a much simpler fix, but no idea how to go about it. Just a thought.

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In some lenses-laminated types the adhesive (glue) used to pair to them together is called balsam or Canada balsam. Its a turpentine type (based glue-resin) broke down in oil and used as a cement.
Once it's dry it's invisible just as you described. Balsam is used to laminate and construct light prisms lenses etc. When the balsam starts to deteriorate it can be the cause of cloudiness, hazing rainbow effect when viewed externally etc.

Sometimes I think a mold develops in or around it that turns black or is off colored like we see in old scopes or in camera lenses distorting the final image which looks like has a speck in it once developed.

I have text here that describes how to select the materials for creating and repairing graticle wires from both natural and man made products during the early experimentation/production of rifle scopes but it does not delve entirely into lens making or provide enough information to avoid damage by misdiagnosing the problem.

Only that one way to fix is to subject the lens to steam to re liquefy the balsam adhesive.
For which it can sometimes be pressed back together to squeeze out the contaminates or eliminate bubbles, fish-eyes or other optical defects to restore original clarity. The amount of adhesive used is usually more than enough that a certain amount of maintenance can be done by the end user until an additional amount needs to be reapplied.

My problem is not being able to determine whether the lens is glass or plastic. If the lens is laminated or even if the origin of cloudiness is in between the lens or on the exterior. I can tell that it appears the interior or scope tube side of the lens seems to be the origin of the problem where it should never have been subjected to abrasion or external damage from rubbing or scratching.

When a drop of water is applied to the lens it clears up until its dried by warm air and when examined in strong light then held at an angle there appears to be no scratches or defects on the exterior.
Soon as you move it around to look at the edge is when you begin to lose sight so to speak because its clear and hard to view accurately because its delicate.

As far as I know it may have had some sort of coating on it that has just become degraded and may only need re coated to restore the clarity.

The coatings used on the lenses can also support mold growth. They will lead to cloudiness if it get bad enough. But even a small amount will reduce the light transmittance. The coatings are used to reduce internal reflections at the glass/air interfaces.