9x11 inch split back printing frame for prints up to 8x10. Requires a 1/8" thick sheet of glass 9x11 inches (I got one cut from my local hardware store for about 5 bucks.) A thin sheet of felt adhered to the backplates should help the negative and paper sit completely flat against the glass but doesn't seem to be 100% necessary.
The springs should be printed in PETG to prevent them loosening over time due to creep, though they should probably still be stored uncompressed. They will need to be sanded to fit smoothly under the tabs on the frame once everything else is assembled. The exact amount will depend on your printers tolerance, slicing settings, and quality of the supported surfaces.
To assemble the frame, place the frame segments on a flat surface. Slide the clips into their slots (they will need to be sanded as well. You want them to be snug, but not so tight that they have to be hammered into place.) Make sure the corners are square and add a couple drops of thin super glue to the joints. Epoxy will work fine too, just apply it before assembling.
The hinges of the backplate should just slide together. If it feels like it wants to bind up lightly sand the pegs, especially the supported surface. No fasteners are needed as the edges of the frame will keep the halves from separating. Put the screws through the openings in the springs, making sure they spin freely, and screw them into the backplate. Finger-tight is fine but you can also snug them up gently with pliers - just don't go full 200lb gorilla on it. Remember to tighten to the German specification not the Russian one (i.e. Gutentight, not Brokenoff.)
***Edit 9/18/2024***
I have been made aware of an issue in which, when attempting to slice the frame segments in Cura, the segments get treated as 2 sets of 4 identical segments instead of 4 mirrored pairs. This is a bug stemming from how Cura handles .3MF files. As a workaround, I have uploaded the frame segments in .STL format as well for Cura users. The other files should be fine, it seems to only be an issue when some bodies have been mirrored.
The author marked this model as their own original creation.