Upon discovering the spool holder design by “Tech with Kramer,” I found it nearly met all my spool holder requirements. However, I realized the printing process could be more efficient, as rollers of that size with an integrated shaft were less than ideal. To address this, I redesigned the roller into multiple, support-free parts that easily press-fit together without compromising strength.

Assembly Instructions

1. Post-Printing: Carefully remove the rim from each of the two rollers.
2. Dowel Insertion: Manually insert the dowels into the rollers. Due to the intentionally tight fit, you might not be able to fully insert them by hand. I suggest using a clamp to help force the dowel into the roller. As an alternative, you can press the roller against a hard surface (like a floor tile), dowel-end down. This method worked for three out of four dowels in my experience, but exercise caution to avoid injury.
3. Bearing Installation: Once all dowels are flush with the roller ends, place a 608ZZ bearing (a common type for spool holders) on each side of each roller.
4. Final Assembly: Slide the roller, now equipped with bearings, into the slot on the base plate.

Final Notes

• I suggest using a spool weight for 250g spools to ensure stability. Without it, the extruder's pull on a lightweight filament spool may cause it to topple. I personally use a 40mm steel rod cut to size, weighing approximately 450g, which is an ideal fit for my 250g spools. You can see how it works in the last picture. If using a spool weight isn't feasible for you, consider adjusting the holder's position so that the pulling force is directed horizontally or slightly downward. This adjustment can help maintain stability during the printing process.