Ender 3 Bulldog Direct Drive Hot End

thingiverse

UPDATE 11/18/19: I've tested out a replacement for this mod and it works perfectly. If you're feeling adventurous, give it a try. https://www.thingiverse.com/thing:3816004 Update 7/8/19: A commenter asked about how to assemble this mod, so I added photos to clarify the process. I have the model assembled if anyone is interested; just can't upload a .step file (check the comments for it now). Keep in mind that you may need a shim (flat washer) to fix any misalignment issues with the Creality Heatsink. I've used this configuration to push four spools of filament through, and it works flawlessly. The magic e-step number for me was 107; I experimented and found that Bulldog makers recommend this setting, which worked great. There's no under/over extrusion, and any wacky spots are well within the feed rate override (I haven't touched it and printed most of the awesome MPCNC files and my upcoming Mostly Printed Quad Copter with no issues). Update 7/1/19: There was a cascade of problems, including a failed hot end fan, a failed x driver board, and other glitches that needed to be sorted out. I've installed the revision and would recommend adding connectors to all wires going through this mod; it makes swapping out blown components much easier. Regardless, I've replaced all TMC2130 V3.0 SPI boards, fans, hot ends, and rewired everything basically from scratch. I also wouldn't recommend putting the control board under the Lack Table enclosure - it's a nightmare to work on. Here's a video of it in operation: https://www.youtube.com/watch?v=PN6U2HKLrDY I'm planning to design a less bulky part cooling duct and a mod to use low-noise fans; the machine is whisper-quiet with the TMC2130s, but it's a shame I have these 747-sounding fans on it. I'm also looking at ways to get the BLTouch closer to the nozzle - more updates to follow. Update 5/20/19: I made a small revision to the Bracket; it's tiny, but necessary to remove any flex in the unit while extruding or retracting. I've put over 100 hours on this setup and it works really well. If you've downloaded the files previously, please discard the old bracket and use the one marked Rev A. Update 5/11/19: I'm finally printing something! Bed leveling was a trick to figure out and the Z-Offset drove me crazy. FYI, I see some revisions in the near future and will post them as I make them and discover more. https://youtu.be/C25E7jVj4vM Note that the Bulldog extruder clone costs $11; maybe $1 in hardware, $6 for an all-metal tube, and a couple dollars for filament. This is only a 3-part mod that utilizes JohnnyWhiskey's Cable chain. I designed this to use a direct-drive Bulldog extruder. You'll need various 3mm and 6mm hardware, as well as an all-metal 6mm hot end tube (I have a Micro Swiss clone that I'll swap if there's an issue). You'll need to notch your gantry carrier plate ~3mm deep x 25mm across; see the photos for reference. Stops are removed since I'm using 2130s. Finishing up the wiring, but so far so good - it's compact and tight, IMO. Wiring is all contained and no more spaghetti mess like the Ender comes with stock. Brain and electronics are under the Lower Lack Table. FYI, I swapped the 24v bed for a 120v, 500W heater powered by an SSR; just because, and I wanted to pull as many watts off the Gen L as I could. I designed this in FreeCAD, so there isn't an assembly file. If someone wants to mod it, I can post the files. The table connector can be found here: https://www.thingiverse.com/thing:3484755