Fostruder-S (dual motor extruder)

myminifactory

Human: 1.75mm Dual Nema 17 Extruder Design Inspired by Elliot Foster's Work I created this 1.75mm dual nema 17 extruder design out of curiosity, but it has been working well for me over the past few weeks with various filaments (PLA, ABS, PC, NinjaFlex, TPU, Nylon). The block features two hinges that can be adjusted using tensioning screws to set the gap between the drive gears. Motors were connected in series and driven with 24V, 1.3A. You may want to hook them up in parallel depending on your specific setup; however, I'm not sure if you can drive motors in series with 12V, and high current stepper drivers might be required for enough torque when using parallel connections. Parts Needed: * 2 - Nema17 motors (max 22mm shaft) * 2 - E3D hobgoblin drive gears * 1 - 1/8" threaded bowden coupling * 2 - M3 threaded inserts * 2 - M3 x 25mm screws * 8 - M3 x 10mm screws * Optional series motor connector (I got mine from Peter Stoneham) Print Settings: Printer: Eustathios Rafts: Doesn't Matter Supports: Doesn't Matter Notes: This design can be printed with or without support, but the filament path has some diaphragms that need to be removed. Use a 2mm drill bit to remove them. Post-Printing Assembly: Remove any diaphragms in the filament path. Install M3 threaded inserts. Use 20mm screws to adjust tension (you can use longer screws and springs instead if you prefer). Install Hobgoblin drive gears on motors (do not tighten) - trim set screws if they stick out too much. Attach both motors to extruder block, aligning set screws for access through the gap in hinges. Tighten set screws through gaps while keeping them aligned with center of gap. Install threaded bowden coupling. Wire up motors however you like (in series with an adapter board in my case). Run motors, check for extrusion direction, ensure no interference between motors, adjust tension, and verify tooth marks are deep enough and symmetric. I usually tighten tension screws until the hinge gap is about 1.5mm. Design Customization: You can edit this design in OnShape if you need to make any changes (different drive gears, filament diameter, bowden coupling, etc.). I chose not to use MK8 gears since they're cut too deeply for dual driving 1.75mm filament without offsetting them.