These bits are complete recreations with a caliper and much experimentation of NWRepRap (which is a modification of the Prusa Mendel) print on reprap.org.  All were designed in OpenSCAD and those source files are included.

These modifications of the parts allow for the following:

• Filament runout and monitering using a bigtreetech sensor (v1)
• Wiping using a wall-mart sourced nylon (or metal) brush
• Changing of the wiping bit easily
• Printing everything without any supports.

The BigTree unit (if you have v2, you'll have to change the source file for it) … uses nylong pipes … which go to the extruder.  I added a mount for the pipe endpoint to the guilder.  It also tries to make sure the hobbed bolt gets better purchase on the filament.  The BigTree sensor itself mounts on the Z-Axis motor mount (meaning filament comes from the right).

The left x-axis bit is modified to have screw holes for the wiper.  The wiper can print flat on it's back and holds the cutoff portion of a brush (see picture) between it's lip and the nylon tie you can thread through it's holes.