Dan,
Thanks. It’s really good to know that my range of choices is a bit broader than I thought.
The Convertible has a removable lens board. Although only one lens was ever made for it, I have seen a picture and a description of a lens, in a different shutter and helical, mounted on a plastic board that slides into the Convertible’s mount.
That inspired me. If the rear elements don’t extend into the space between the board and film, a lens could be mounted on a board and it will slide in and out, like the original lens/board.
Alternatively, I could fabricate a board that stays in place, but would accept the Mercury Works 3D printed parts - spacers, helical for view lens in shutters or the 3D printed Mamiya Press mount. I could also use the Mercury camera body and I’m done once I get the lens.
I often wonder if I should have just bought a nice 6x9 folder, or a press camera, or a Makina, but I‘m enjoying learning about cameras, lenses and this relatively new world of 3D printing. 3D printing materials accessible to the hobbyist are perhaps not the best for cameras, but they can work with proper design.
I thank all the folks who share their knowledge and experience on these fora.