Best 3.5kg Spool Holder

prusaprinters

<p>Finally, a good 3.5kg spool holder! I like to print big, and a lot, so I use 3.5kg spools with a reverse bowden tube to my printer. I could not find a decent spool holder setup for these massive spools that didn't cause print quality problems. After many designs, this is the one that works perfectly and is very simple to use. And, it works with standard 1kg spools too.</p><p>Extruders need a low resistance, consistent pull filament system. If there is too much or too variable of resistance, then the extruder will be pulled up and down on the z-axis and cause ringing and under-extrusion problems on the print. If there is too little resistance, such as with a bearing through the center of the spool, then the inertia of the spool would cause it to keep spinning, unwind too much filament, and inevitably a filament tangle.</p><p>The sweet spot is a simple non-moving support through the middle of the spool. This causes consistent friction that is just high enough to stop the spool from spinning freely, but low enough to show no evidence of filament feed problems. The center support in this design is tilted 2 degrees so the spool will not migrate off of the holder. If you print two, then they can be zip-tied together through the hole at the top and help balance the cantilevered load. But, one has enough structure to stand alone.</p><p>This is a big print, but it fits on a 200mm x 250mm standard prusa bed. Use lots of perimeters (2mm+) for lots of structural rigidity.</p>