Prusa Core ONE removable heavy spool holder with support

This removable spool holder can hold heavy spools and take some load of the extruder with bearings. One part screws into the Core ONE where the original spool holder is placed on the side panel. Then there are three different spool holders with different lengths. The longest one is suited for heavy spools and has bearings to take some load of the extruder motor. The two smaller spool holders do not have bearings. The bearings are 22mm in diameter, 7mm thick and the hold is 8mm (8x22x7).

For the one with the bearings you will need 135mm of M8 threaded rod and two M8 washers. Place the bearings in the long spool holder. Start by screwing the threaded rod to “spool-holder-ROLLER_96mm_OUTER_v3”. Place a washer on the threaded rod and put the spool holder with the bearings onto the threaded rod. Place the second washer on the threaded rod and attach “spool-holder-ROLLER_96mm_INNER_v3” and tighten is slightly. This assembly can now be hooked into the part that is screwed to the Core ONE side panel and you are done with this part.

For the support arm you will need a M4 nut and a 30mm M4 screw with a hex head. The support arm starts with “removable_spool_holder_SUPPORT_BOT” and “removable_spool_holder_SUPPORT_TOP”. Put the latter one in the slot in the first part, with the indented slot facing out. Take the M4 scre and press it into “removable_spool_holder_SUPPORT_KNOB” and put the “removable_spool_holder_SUPPORT_KNOB_COVER” over it to cover the screw head. Press the M4 nut into “removable_spool_holder_SUPPORT_NUT” and place it into the indentation in the sliding slot in the two bigger parts. Screw in the M4 screw into the nut from the other side. If you want, you can print “removable_spool_holder_SUPPORT_SHOE” in some soft material like TPU or foam and place it on the bottom of the support arm, or just glue some felt feet on it.

The shorter spool holders are for lighter spools like 1kg or so and do not have bearings and they do not need the support arm.