Paterson-Compatible Film Reels (All Sizes)

I needed some reels for APS (24mm) film. I was inspired by the excellent work of @thinbegin on Printables.com, but his models didn't fit my particular developing spindle. So, like any well-adjusted person, I spent too much time making my own parametric design with a compliant central core. The core makes it a bit more adaptable to different printers and different spools. At least, that's the theory. Let me know how it works in practice!

100 microns is the tightest tolerance for this design. Unlike @thinbegin's designs, these go together once with superglue and don't disassemble. Most thermoplastics are compatible with film developer solutions, and superglue is safe once cured. I used PETG for a little bit more heat resistance than PLA. When you assemble the reel halves, make sure the smaller end of the spiral rests inside the groove of the top spool, otherwise the halves will be set the wrong distance apart. You should feel it “click” down into place by about 3mm when properly seated, and you should visually see that everything is sitting flush.

Of course, since the design is parametric, it's easy enough to make a variant for some of the more common film sizes. I currently have 110 (16mm), APS (24mm), 126 / 135 / 828 (35mm), 127 (46mm), 120 / 220 / 620 (60mm), and 116 (70mm) variants. If you need a size I haven't posted, drop me a message and I can make a new one. I've also included a STEP file for each variant in case you want to play around with it.