DMK8 Directo - The Dual MK8 extruder, Direct version.

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Dual MK8 Extruder The Bondtech (Cheap) Extruder The core of this extruder is the power transmission using a bolt axle that also serves as the lever arm. I added an MGN15 mount, allowing you to modify a single part and install it wherever you want. Changing one part enables a transition from direct to bowden. You need to properly build, assemble, and test the gears. I designed this extruder a year ago, long before I knew about the existence of Bondtech gears in the material plane. Now, I'm publishing it in two versions: direct and bowden. It uses two MK8 hobbed gears, with one requiring adjustment by sanding it down (taking off 0.3-0.4mm) on a drill. The gears need to be built using nylon; don't even bother with PLA or ABS as they are press-fitted. You'll need three 5x75mm hexagon head bolts. Parts can be made from any material you like, but try to avoid TPU or chocolate. If you want to use 1.75mm filament, assemble it without the MK8 gears and drill a 2mm hole where necessary. For 3mm filament, you get the idea. Printing nylon gears is a nightmare – try using horizontal expansion settings in Cura. Don't forget to apply some grease. Assembly instructions can be found here: https://a360.co/2tIRme1 Use your brain and follow the link; the gears may be a hassle. The BOM will be updated soon, but for now: You'll need lots of strange ball bearings – this thing is made to last. Check out the assembly instructions for details. BOM: 3 - 5x8x2.5 6 - 5x13x4 Use ABS or PLA for the chassis. Nylon for the gears (two large ones, three small ones) – print plenty and experiment with size and horizontal expansion. The small gear in the stepper might need to be smaller. You'll mostly use M4 bolts, along with two 55mm M3 bolts to secure the filament.