Scalable Joinery Clamp

I've had some cheap, ABS joinery spring clamps for nearly a decade and all the small ones have snapped on really surprisingly thing clamping jobs, so I decided to replace the lot with PETG clamps. Queued for printing, will upload photos when completed. This is my finalised design, tuned from an earlier one, based on a CNC model, and from a clothes peg design, which I plan to refine before uploading.

21/7/2020: Updated/simplified the design. The elastic band notch was a weak point, so I simplified it. Also, while the Cura settings below work well, the clamps can be stronger and lighter if you use 40% cubic infill, rather than 20% grid. Uses slightly less plastic for a more rigid infill.

Essentially, these are a spring clamp made in two identical parts, where one part is turned over to dovetail into the other, with an o-ring of appropriate size or a rubber band looped around a few times for a spring. (O-rings recommended for the larger ones.) I've sliced mine at 0.2mm, 20% infill and at 40mm/s print speed in Cura. A little fast for PETG, but shiny quality isn't the prime factor here. I'll be using black 3D Fillies PETG. You could probably use up fag ends of rolls for a job like this, or, if you're rich, PETG/CF composite. (I have a few lighting clamps out of that stuff. AWESOME!)