This is a cooling fan adapter for the Folgertech FT-6, applicable only to the dual extruder option. For use of larger diameter nozzles, the need for adequate cooling becomes immediately apparent. This solution utilizes two standard size 5015 blower fans (I used the Winsinn ones off of Amazon: https://www.amazon.com/WINSINN-Bearing-50x50x15mm-Extruder-Makerbot/dp/B07DB7DLMM). You will need additonal hardware:
(4) M4x20 screws
(4) M4 nuts
(4) M3x16 screws
After printing, install by removing the cooling block fan and replacing the screws with the M3x16 screws, attaching the bracket to the outside of the fan. You may want to reorient the fan to have the wire coming out the top for easier routing. Attach the blower fans into the ducts and secure with the M4 hardware. Hook up the blower fans in parallel to the fan inputs on the extruder carriage board. A note: you may need to reposition your bed leveling sensor with this modification. You will definitely need to re-run your PID settings with the fans on after install.
While this is intended for the FT-6, it should fit on any of those cyclops clones with the same exact geometry such as this 2 in 1 out extruder: https://www.aliexpress.com/item/32796885685.html (non-volcano size only) There's also a branded one using the same geometry with 'NF' marked on the cooling block that could work. There's a bunch of clones with different geometry out there, so it's up to you to check if you intend to use this elsewhere.
Monoprice Maker Select V2.1
0.2 height, 0.4 nozzle size
You will need supports, supports should be only supporting portions of the model over the build plate (I.E. do not fill the internals of the ducts). Orient with the bottom down on the build plate as it would be installed (the flat parts of the ducts to the build plate, hot end cooling fan mount oriented vertically). Uses ~14g of material at 100% infill.