FrankenCamera assembly. I started with a Minolta Semi 645 camera body with the door and bellows removed. I also removed the crumbling leatherette and sanded down the outside of the body.
The night before I epoxied the lens plate to the 17-31 M42-M42 focusing helicoid and mounted the Wollensak Velostigmat 50/4.5 lens so it would be ready to go today.
I started off by cutting a plate out of .35 aluminum, drilled holes in the corners (and tapped them using a 10/32 drill/tap/deburr combo bit) for so I could screw in a lens plate later on. I also cut a rectangle out of the middle for the lens light access.
Next, I cut a plate that was the same size as the mounting plate for the lens to mount the lens to and and then bolt it to the mounting plate. I cut a hole a bit larger than I wanted to out of the center of the lens plate. I would have liked it to be exactly 42mm across so I could screw the helicoid right to it but it ended up about 43mm instead. Forgive me, I’m a web design/graphic design professor, not an engineer and I’m using wood-working tools on aluminum. I ended up filling the gap with gaffer’s tape and screwing the helicoid to the tape.
Step the next (not shown), I spray painted the insides of both plates matte black. Then I epoxied the mounting pate to the camera and filled the gaps with black silicone.
I mounted the lens plate directly onto the mounting plate and found light gaps to be plentiful. I got a piece of craft foam and cut a gasket to sit between the plates.
Finally, I screwed the lens plate to the mounting plate and found that one of the bolts contacted parts inside so I fashioned a shim/washer from some leftover aluminum.
The bad news is with the extra depth of the gasket and the tape, it won’t focus to infinity. In fact, the furthest it will focus to is about 18". I’m not sure how I can take three or four millimeters out of this design to make it focus at infinity without mounting the lens directly on the mounting plate.
Still, the point wasn’t to get a 645 camera with a 50mm lens, it was to prove the concept and in that it works wonderfully! I need to get a 75mm lens and mount that to a helicoid and build a lens cone for that lens. And a lens cone for my 65mm f8 Schneider-Kreuznach Super Angulon (currently mounted to another Frankencamera).
I shot a roll as a test. It might be next week before I can develop it.
