Beam Parts

• Start by printing the two solid mounting beams in PLA or ABS. Clean them up then use an M3 screw to secure them to the top of your frame, leaving enough space for a filament spool to fit between them. You can leave the screws loose enough so the beams can be slid around, but they should not be able to deviate too much from straight up-and-down.
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  Note that the beams are printed on their sides so that the mounting grips won't need any support material. I recommend printing the beams with 10-15% infill for lightness and strength. You could try adding lateral through-holes to the beams to add perimeters and see how it affects rigidity. Printing solid is simplest and ensures that the front and back layers will have lots of long perimeter filaments for strength, and a low infill is sufficient for integrity.
  Top Parts

• The package includes two types of spool mounts…
  Rod/Bearing Holders are made to hold an M8 smooth rod or two 608ZZ bearings with an M8 smooth rod in the middle. (The SCAD includes an option to incorporate these in the beam parts.)
  Flexible Clips are made to fit 20mm and 30mm spools. Designed to be printed in PLA for optimal flexibility, but should work fine in ABS and nylon too. Configurable in the SCAD file.
  Spindle Adapter

• The spindle adapter is parametric, so if you have spools with a larger center hole or outer spindle you can set them up here.
  Other Options

• There's an experimental option that makes beams with narrow scaffolds, but this geometry is too weak to recommend. Try playing with geometries that can be strong while reducing material usage and see what you can come up with!