Smooth feeding spool holder

prusaprinters

<p>I designed this spool holder when I upgraded my Ender to direct drive as I found that the original holder created uneven tension on the extruder and z-axis as the filament rocked back and forth. Meanwhile other holders with bearings instead fed too easy and unspooled the filament or were simply too big to fit some spools onto.&nbsp;</p><p>Fits original Ender spool holder bar and nut.</p><p>Some holes only have pilot holes that needs to be drilled and tapped.</p><p>The friction can be adjusted by choosing the appropriate smaller o-ring thickness and fine tuned by tensioning the two roller screws.</p><p>BOM:*</p><p>2 pcs 608ZZ Bearings</p><p>4pcs 2.5x20ID O-rings</p><p>2pcs 2x10ID O-rings</p><p>4pcs M4x12 Screws</p><p>1 pc 8x88mm aluminium rod with threaded ends for M4 OR printed alternative part</p><p>*screw and o-ring size is not critical. use longer screws if you go with the printed axle as it carries axial loads to eliminate the bending moment of the holder.</p>