Zeepro ZIM bottom extruder V7

thingiverse

Update Sept.2015: Successfully printed multiple spools (kilograms) with this configuration, resulting in absolutely great prints - feeding a new spool can be a bit tricky as previously mentioned. Printable without support, I included "printhelpers" for the first layer to ensure better adhesion on the bed, which need to be removed afterwards (the magenta surfaces visible in the CAD screenshot). At least one M5 pneumatic fitting is required for each side - if you also want to guide the filament into the extruder block, another one will be necessary. I used a piece of an M3 rod and two nuts on the bottom so that the rod won't turn when tightening whatever is placed over the spring (M3 kurled nuts were purchased). Sometimes it's challenging to stick the filament into the extruder block due to the pneumatic fittings - it works every time at my ZIM, but occasionally I need a minute or two.