Double fan cooling for Prusa i3 MK2 and MK2S

thingiverse

Since purchasing a printer, I have encountered issues with overhanging objects that sometimes cause the PINDA probe to hit. To resolve this problem, I modified the newest B3 nozzle-fan design from the MK3 model but the issue persisted. Therefore, I visited the e3d-online store and purchased additional fans and V6 Silicone Socks, then reworked the MK3 B3 nozzle-fan design for a dual fan setup. I tested this new configuration on a temperature tower with temperatures ranging from 190 to 220 degrees Celsius at a height of 0.2mm. The photo shows the stock MK2 temperature tower on the left and the dual fan setup on the right. The sock must be placed on the nozzle since the cooling component is approximately 2mm away from the nozzle. If not used, the part may melt. However, I cannot guarantee that it will not melt in areas near the heater cartridge as they are uncovered by the sock and only 0.5mm apart. I printed parts from PETG material. The fan holder and extruder cover were printed at a resolution of 0.2mm, while the nozzle fan was printed at 0.1mm. The extruder cover required support during printing. To achieve quality prints, I recommend increasing the speed of the nozzle fan to at least 30% since there are steep overhangs involved. You do not need to completely disassemble the extruder; simply remove two front screws from the heatsink fan located on the left side and two screws from the extruder cover below the stepper motor. If you cannot figure it out, you can try to solve it yourself. Cut off the zip tie that holds wires at the bottom of the extruder. The original Prusa fan wire is short, so I disconnected it from the back of the fan and extended it near the extruder. I then soldered new fan wires in place, making sure to match the red wire with the red connection and the black wire with the black connection. The STL files are not properly oriented; however, there is a photo that shows how the parts should be placed on the bed. STEP files are also included. Edit: I have added the MK2S extruder body with a shorter PINDA holder to accommodate the MK2S model. Alternatively, you can simply cut the original PINDA holder to fit.