Opening up a 21mm chrome Leica metal viewfinder

[Magnus F I]

Hi, Rangefinderforum. I've acquired a 21mm chrome Leica metal viewfinder, but the corner of the front glass is chipped, and this has caused dust to gather on the front glass from the inside. I want to open it up, remove the dust, glue a small piece of plastic in the chipped corner, and close it all up. However, I can't find any screws on the outside. Anyone has any experience with this?

I attach a picture of the viewfinder in question.

Thanks!

 

[Particular]

Hi, I have had one of these apart before. There are no screws, because the front element is glued in. In my case someone had already opened it up and glued it back, but not very neatly. I managed to pry the glue out from the crack with a needle, going round carefully until it came loose. I cleaned everything and glued it back with silicone. My thinking was that that would be easier to redo if I needed to. I presume that Leica used epoxy, so applying heat may help. What ever you do, don't use super glue as it will fog the glass.
The problem I was trying to fix was that the frame lines were at an angle. I realized that they are not accessible from the inside. The lines are coated onto the rear element. I was unable to unscrew/unglue the back ring, but finally realized that I didn't need to. The rear element was a little loose, so I used some tape on the glass to grip it and rotate it into position. I then secured it with some silicone.

 

[Magnus F I]

Thank you, that's extremely helpful! I'd probably have used superglue if I hadn't read that.

 

[Particular]

Opening up a 21mm chrome Leica metal viewfinder

I used clear silicone which is only noticeable on close inspection. It was easy to clean up and ended up being very neat. Once you slide the front element back in it will likely ooze out the front, so what I did was cover the front of the glass with magic tape, and then remove it cleanly. They also sell tubes of black silicone which should be very slick.

As for the super glue, I made that mistake once, but not on an expensive finder.