DIYS Leica rangefinder mechanism

[CheekySquid]

Hey everyone! I'm working on a personal project to build a rangefinder camera (almost) from scratch, but I'm having trouble finding detailed information on how the mechanisms actually work. I understand the general principles (sliding element, rotating wedge) but I was hoping to find proper documentation, detailed specifications, or even a full disassembly breakdown.

I took apart a Zorki 2C to study the mechanism, but for my project, I want to integrate a combined rangefinder/viewfinder and aim for performance on par with Leica rangefinders (though I've never actually used one in real life).

If anyone has resources, documentation, or could point me in the right direction, I’d really appreciate it!

 

[Sonnar Brian]

You would probably try taking apart a camera with a combined VF/RF. Then decide if you want projected framelines. I would suggest you buy a "for parts" Canon 7.

For some history of a Rangefinder- these were used on Naval Vessels as gunsights. Some of the math is in this:

https://www.admiraltytrilogy.com/pdf/FI2024_Development_of_Optical_Rangefinders.pdf

 

[CheekySquid]

Thats a good idea, I might do that. I think I've figured out how the Leica rangefinders work now, but I just don't know what the mechanism is called. It looks like a swinging wedge almost but without the convex lens.



The object circled in red swings back and forth (up and down in this pic since the camera is lying on its back) and that brings the patch in and out of focus. If anyone knows what the name of this mechanism is called it would be a big help.

 

[raydm6]

I have been in the hi-tech field (Engineering Configuration Management) most of my working life and would love to see some exploded view, detailed and dimensioned drawings with material call-outs (and any post-fab process) for vintage Leica cameras. That would be very interesting!

This example is the closest I have seen: a Spare Parts List/Exploded Views Manual 🔗. What is missing is the detailed/dimensioned/ engineering drawings w/material call-out.

A detailed list of Leica M3 spare parts issued for internal use by Leitz, including three hardbound photo books, one for each production variant of the M3: 700001-746500, 746501-782000 and from 782001, all beautifully illustrated and in excellent condition, also incl. a large folder with exploded views of all elements of the camera, and listing all the parts (also for various versions of the M3), around 100 pages, in excellent condition

Leica M3 Spare Parts Lists / Exploded Views | AI_37_38767

A detailed list of Leica M3 spare parts issued for internal use by Leitz, including three hardbound photo books, one for each production variant of the M3: 700001-746500, 746501-782000 and from 782001, all beautifully illustrated and in excellent conditi…

www.leitz-auction.com

Curious, what's in those three binders on the right?

 

[raydm6]

Free Leica M3 Repair Manual:

Leica Repair Manuals | website

A collection of Leica repair/service/parts list manuals.

www.cameraworks-uk.com

Hard to read exploded view for M2:

 

[Sonnar Brian]

I found the M2 service manual, includes a section on the VF/RF,

 

[Sonnar Brian]

And the IIIf.

I found these back over 15 years ago.