Please send feedback after installing and let me know what refinements might need to be made. FT-5 users should also be able to install this if you are running direct drive.
Edit: I added pictures of an extra step which combats rubbing if you’re homing Y all the way over to the crappy end stop switch design. Countersink an M8 bolt into the original location of the inner panhead Allen bolt securing the Y axis to the X guide rails. This corrects a minor rubbing issue while homing.
This is a high-powered parts cooling system for the Folgertech FT-6 gantry with a direct drive extruder. It takes two 24v 50mm blower fans which you will have to wire to your MKS board at the labeled connector, just above the nozzle heater output. Alternatively, you can run either of these fans by themselves.
The front fan is installed by piecing the three tubes together with super glue. No bracket is necessary and tube #1 fits snuggly into the fan without mounting hardware. The fan can then be installed to the ACM board by drilling to 3/32" holes into it. M3x20 bolts will thread right into the ACM without pre-tapping. This is direct bolt-on for my extruder mount assembly found in my design portfolio.
The rear fan will bolt to the back of the cover for the gantry board with M3x18 hardware. M3x20 (what is commonly available) will poke through, sue me. You'll likely have to shave 2mm off of the 20mm bolts if you want to find something locally. If the bolt holes don't line up perfectly, use just one or none and glue the fan case with the hole centered and the output at the correct angle. I can't guarantee fan fitment because I winged it and was slightly off on my own cover. I made adjustments to the STL based on mine but haven't found a need to test print another overly-complex piece to see if I got it 100% right. Please let me know if you try it for yourself how the fitment is. After the fan is mounted, the cover will clip to the circuit board and act as a nice cosmetic cover. Glue the fan tubes together. The bracket for the this tube should also be glued on but use it to align the tube where you want it before glueing. If accepts M3 hardware and will fit under the M3x20 rear/lower bolt for the Fan #1 where it mounts to the ACM or you can mount the bracket straight to the ACM with M3x5 hardware if you are not running the fan #1. I recommend running both - the cooling potential is amazing or you can run both at 50% for reduced noise over running just one at 100%.
It is recommended to print these coolers out of ABS and to run a silicone sock on the hot end. An MK7/8/9 sock fits the factory extruder. I'm personally using PLA as this printer will only be used to print low-temperature materials with cooling, thus I added extra insulation to the tubes near the hot end. It has worked great.
MK8 extruder (I retained the original stepper and extrusion tube/nozzle):