40mm extruder fan adapter plate for late 2013 Printrbot Simple

thingiverse

I figured out that most of my print failures were caused by heat creep, which is premature softening of filament as it passes through the extruder, causing the drive to slip and/or jam. Active cooling came to the rescue. A parametric model of this design is available on Onshape, a public document. I'm not sure how to link to it directly, but you can find it by searching for 40mm fan adapter plate for 2013 Printrbot Simple extruder. The document contains two part studios: one for the extruder plate and one for my DC power connector mount. I started with Joel Crane's 30mm fan mount plate. Initially, I hacked with OpenSCAD to add a larger diameter opening and assumed the 40mm fan bolt pattern would match the extruder mounting bolts. Not quite. I imported the design into Onshape using FreeCAD to convert the STL to STEP format. I used the imported object as a reference for a fresh sketch. This version, posted here as jmd-extruder-plate.stl, adds a spacer to clear the extruder mounting bolts and new offset mounting holes (45mm diameter) for the fan. I built this with a 12v 40mm fan from Radioshack and a DC power jack from the same company. The jack connects to a compatible power supply I have for a small rotary multi tool. It would be possible to power this from the heated bed circuit on the printrboard, but for now, the separate power supply is simple enough.