Tinik spool rewinder

prusaprinters

<p>I got a little tired of the buffer system that came with my MMU2 so I decided to make something that would suit my needs better.&nbsp;<br>Initially I used printed springs from PLA, but they didn't last very long and would not work at all in a heated enclosure.<br>This version uses a steel spring found in these retractable tape measure devices:<br>https://www.amazon.co.uk/Hanyousheng-Measures-Measurement-Retractable-ScaleTape/dp/B097GDSPXK?ref_=ast_sto_dp<br>They are glued together so be careful when you pry them open so you don't hurt yourself or damage the spring.</p><p>The rewinder works more or less like any other spring loaded auto rewinder I have found except from the spiral in Part_6 which limits the number of turns to 2.4 with the intent to save the spring and allows for easy pretension during assembly.</p><p>Check all close assembled surfaces for smoothness and sand slightly if necessary. Usually the top surfaces after printing.<br>Take caution when assembling the steel pins so they don't protrudes too much. Especially the 2x9mm steel pin which must not touch the bottom of the spiral.</p><p>The center axle will need some modification to fit any other system.</p><p>The roll are 75mm in length and the diameter is 48mm</p><p>All dimensions are metric.</p><p>Parts per rewinder:<br>2 x 608 ball bearing. Must rotate freely! Degrease if necessary.<br>1 x m3 hex nut<br>1 x m3x12 socket head screw<br>1 x steel spring mentioned above<br>1 x steel pin 2x15.5mm<br>1 x steel pin 2x9mm</p><p>Print settings:<br>Layer height 0.2<br>Perimeters 5<br>Bottom solid layers 5<br>Top solid layers 5<br>Infill 30%</p><p>Support on Part_1 and Part_2 (bearing seat)</p><p>I should add that the side stop (Part_10) was printed with PETG in my system and may be too stiff if printed in e.g. PLA, especially with the specified print settings.</p>