Extruder/hotend demo set

thingiverse

This is a remix from thing:147705. I adapted it to use my bearing 16x5x5mm (625ZZ) and made the idler in two parts, making it more rubust with an metallic axis. The thing is not intended as part of a real 3D-printer, I use it as part of my 3D-printer demo set. I use the hotend part (old leftover from myPrusa i3 mk1) to check and clean nozzles. A Arduino Mega 2560, a cheap Ramps shield and the Pronterface program are used for control. The SCAD file is quite messy, partly because it is based on an extruded dxf file, and partly from my rough extra cutouts. The original idler is split in two to give better support for the bearing axis. The two halves are kept in place by two internal pins during assembly and by the hinge (M3) on one end and a M2 screw on the other. The bearing axis is a M5 screw (12mm) held in place by the tight holes. This thing is not intended for usage in a real printer, but just for demo purposes, and maybe inspiration. Modern printers have better extruder designs.