Leica metal auxiliary viewfinders

[alansond]

The rear eyepieces on my Leica aux. finders (21 & 28) have become loose and rotate so that the frame lines are not always in the correct positions.
A bit of glue should stop this rotation. The rear eyepiece frames do slip off so I could put a very small drop of the proper glue between the eyepiece glass and the finder body & maybe another between the rear frame and finder body. Has anybody made this repair & what type of glue do you think would be best. The viewfinders are both metal bodied, about 30-35 years old. Thanks for your help & suggestions.

 

[Al Kaplan]

I used a bit of clear nail polish applied with a tooth pick. The biggest problem is getting the framelines properly oriented. I wanted to use something that could easily be removed with a common solvent.

 

[peterm1]

I had a not dissimilar problem with the "goggles" for my 50mm f2 DR Summicron. One of the goggle eyepieces came loose and rattled - these lenses are rectangular so do not rotate but its none the less annoying. I resorted to a tiny (almost invisible) wedge of toothpick in one corner - it casues no damage and is completely reversible.