Remake to fit with Printrbots and Ubis hotends.
All Printrbot Jr owners should use the base jr
quick filament change
added a baseversion with fanmount. Sometimes the filament got stuck in the lower basetube. With this 60mm fan I had no issues.
download the counterclock version if your mk8 gear turns counterclockwise to extrude, otherwise download the clockwise version
Just print and assemble it. Parts you need:
2x M3 x 10
1x M3 x 25
2x hotend screws ( 1" 6-32 original ) maybe M4 works too (M3 is too small )
1x M4 x 50 or bigger hex screw (best a DIN 931 8.8 )
1x 608 bearing
1x M4 nut
some M4 washers
1x 60mm fan if needed
If you don't have a DIN 931 8.8 screw file the threads of a M4x60 a bit until the spring can slide smoothly.