— Design, engineering and print
A 3D-printed film camera
The K5 Arta MkIII, a fully mechanical 35mm film camera with swappable optics, designed in Fusion 360 and printed at home.
There are no electronics in it. Film advance, the shutter and the release are all mechanical, and almost every part came off a printer. The only parts I did not design are the bolts, the steel spring, the cable release and the metal tripod thread.
The optics mount on a bayonet at the front. I made two pinholes for it, a 40 mm f/150 and a 52 mm f/192, and a Sony E-mount adapter lets it take a real lens, so the same body shoots soft pinhole frames one day and a sharp 35 mm the next. The pinholes were the hard part of the maths: the hole, the focal length, the f-stop and the frame all depend on each other, and getting every one of them to land in the right place inside the body took a good deal of working out.
The grip comes off. Swapping it changes how the camera fires: one grip has a plain button, another takes a cable release, and a new one can be printed for whatever else is wanted. Underneath there is a metal tripod thread, so the long pinhole exposures can be shot from a tripod.
The biggest challenge was none of that, though. It was the film: getting it to move through the body smoothly and by exactly one frame at a time, with printed parts alone. That is where most of the dozens of versions and the dozens of smaller prototypes went, each printed to prove one mechanism before it went into the body. Three full cameras came out of that; the third is the MkIII in the pictures, and the photographs at the end came out of it.
