Brass Lens Front Element is loose / Need help

[maxi0909]

Hello guys, I bought a beautiful Kranz Petzval lens at an auction. But the front glass element is loose.

Maybe I can glue it to the brass mounting, because there is no other way to mount it. No thread like in other lenses.

Maybe you can help me to find a good way to fix this problem. Is there a glue that is good for mounting glass on brass? It should be very solid.

Yes it´s not a adequate way, but I wanna keep it for a lifetime.

I am thankful for everykind of help or tip :)

[goamules]

If you can show some pictures, we can help. Some lens fixtures have a rolled edge, some have a screw in ring, to hold the glass in.

[maxi0909]

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There was this small brass wire t hold the lens... but it was loose and broke off...

[maxi0909]

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This is the wire

[BrianShaw]

That, quite possibly, is a rolled over edge that failed.

[Steven Tribe]

Agreed. I am surprised Kranz used this system. Damage always happens when amateurs like us try to raise the edge, especially when this is the third time it has been done (for rebalsaming every 75 years) since the mid 1800’s.
I have struggled with this mount system many times when changing the balsam and have used ordinary window sealer at the base (very small quantities) when the turnover is compromised. Obviously, the seal has to checked occasionally.

It could also be a primitive “locking ring” pushed into the thread which accepted the screw in mounting ring (lost years ago!