Fan mount for 40mm fan with duct, Prusa v1 x carriage. This duct cools the workpiece.DISCLAIMER: This will probably not work on your printer due to hotend length. It is designed for a J-head mk4 B, prusa v1 carriage with brass bushings. Nominal bed clearance at Z=0 is 2mm.Because this is a contracting duct, it puts back-pressure on the fan. If the tip clearances are too large the fan will stall and move very little air. It is possible to fix this by stuffing little slips of paper into the gap between the blade ends and the fan housing.This was designed in solidworks, so there is no openscad file. Please do not ask for one.The .sldprt file may have some changes that did not make it into the .stl file. I was going to print a second version but never finished it. Also, the orientation it's built in is wrong. You'll have to make an assembly and align the part to the planes so that the duct points up in positive Z. In this orientation it prints very nicely.The duct mounts to the underside of the belt clamps. Minimum screw length is something around 15 or 20mm. You can either leave the belt clamp nuts in their traps and add 2 more nuts to hold the duct on, or use the original nuts to hold everything in place. There are not nut traps on the duct (because in my experience 3mm nut traps are very weak), so you may need to hold the nuts still with small pliers while you torque the screws down.The top hole spacing is designed to match the belt clamps on the stock Prusa X carriage. If you are using a different X carriage I recommend checking your belt clamp spacing before printing.If I remember correctly the fan hole spacing is 32mm.I used slic3r to slice this file, and ran into the thin wall bug about 90% of the way through the print. Fortunately, all this does is slightly shorten the duct, so the part is still usable.