Broken range-/viewfinder unit on Vito CLR

[SalveSlog]

The rangefinder mecanism (to the left in the pictures) has broken off the viewfinder. Part of the once joined surfaces is clear glass that does not seem to have had glue on, and came apart with no damage to the glass. But the rangefinder part seems to have taken with it some part of the viewfinders glass surface. I hope this is visible in the pictures below.

Still when I hold the two pieces together, the system seems to function as it should. I can see the full double image. I believe it would be possible to glue the parts together in alignment, but I'm afraid the the glue will obscure the image. Or that other things can go wrong.

Anyone here have experience or just opinions on this? What kind of glue, and so on...

 

[AgX]

If you would put the parts together and just put a line of epoxy-cement arround the seams chances are great in case you heat-set it that the cement runs into the slit. Thus either having it set cold or use the fast setting version. In short time it will get a viscosity too hgh for any creeping.


Alternatively you could use optical, UV-cured cement completely on the contacting surfaces.


But all would require some experience not to make a mess out of it.
If the rangefinder would sit on its own on the finder, that would be a great benefit for cementing.

 

[SalveSlog]

...
If the rangefinder would sit on its own on the finder, that would be a great benefit for cementing.

You mean while it hardens?

 

[bernard_L]

Alternatively you could use optical, UV-cured cement completely on the contacting surfaces.

+1 that's the correct solution.
see, e.g.
http://www.thorlabs.de/newgrouppage9.cfm?objectgroup_id=196
Suggest you contact them for advice about the best variant in your case.
Or, approach a university lab involved in optics and beg a few drops of glue.
Or, I might be able to send you, for the cost of postage, outdated (but not too much) UV curing glue.
Note: you will need a UV source: HID lamp, Tanning lamp, or... sun (not much hope right now in Norway, even southern...

With epoxy, I would fear poor adhesion if epoxied only on the outside, or ugly creeping if teh glue gets inside (I bet it will).

 

[AgX]

You mean while it hardens?

Yes. Otherwise you would have to make some holding-construction (a good cause for trouble)

 

[SalveSlog]

Thanks AgX and Bernard.

In fact I have a uv-box for drying varnish!

Do you know what kind of glass this is? And would the uv rays really reach the glue?

 

[AgX]

The same way as the rays from the subject to the photographer. Via the respective windows.
When cementing a thick doublet the UV-rays will have to pass even more glass I assume.

 

[SalveSlog]

So I used the glue bernard_L sent me to glue these glass elements (see post #4). I made a wooden fixture to seat the small part in the right place for applying the glue and clamp. Then put it in the sun to harden.

Last picture: I'd like to replace the missing white paint. Anyone got a recommedation for type of paint?

***

The glue I got from bernard_L is expired but still usable, so if anyone need it I will send it for postage just like he did.