This plate allows blowing direct jet of air on the X, Y and extruder stepper driver chips on a RAMPS board. I was most concerned about the Y axis driver as that has been causing me the most trouble. The Z driver gets residual air flow, which is more than enough for its work load. There is a pass-through hole for Z driver current adjustment, the other drivers could be handled by stopping the fan and passing a slender screwdriver between its blades. I designed this for my particular RAMPS controller setup, see the photo for how I located it. This plate might work well with many other RepRap controller boards. You may need to adjust the controller board location, or adjust the drawing to relocate the fan as desired.I used an engraving laser to cut 3mm / 1/8" thick acrylic. Any laser cuttable or routerable material should be fine, as long as it's not too thick. Drill & tap the plate to 3mm thread to mount a 40x40x10mm fan to the top or bottom side of the plate. The plate mounting holes will accept up to 5mm hardware, I used standard 4mm screws and some quick t-nuts from Adafruit for easy and quick access to the controller Use a 24VDC fan if it's a typical MendelMax 2. Make sure the fan will clear the Y table arms the full length of its travel!