Easy exchange filament extruder

cults3d

For a new printer, I needed an extruder setup that would handle ABS printing with ease. Since I print with ABS frequently, this one was designed specifically for that purpose (but it also works well with other filaments). When printing with ABS, you don't want airflow passing through the printed parts, so the air is drawn in from above and then passes through to the Hot-end before exiting at the top. The same airflow design is used for the motor as well, ensuring the printed part never gets cooled by these two fans. To make changing filament easy, I designed this extruder with visibility in mind - on most extruders, you can't see the filament wire, which can make it hard to change filament. If you run out of filament during a print, you're in trouble. That's why I made this one so that you can always see the filament wire. I needed an extruder that could handle three different sizes of filament (1.75mm, 2.85mm & 3mm), so I created an exchangeable filament guide that can accommodate all these sizes. For the 1.75 mm filament, I also had to install a Teflon tube because the hot-end is designed for 3mm wire (I highly recommend using a Teflon tube anyway, as it makes the filament go in much smoother). The filament guide is adjustable so you can guide your filament perfectly. In the photos, you won't see this guide because that's still the prototype model. On that version, the 3mm guide was fixed to the body - not very smart, as you couldn't adjust anything anymore. I also broke it. As a loose part, you can simply print it out again. The guide is mounted using a washer, M3 nut and 10mm bolt. The small filament driver (11mm diameter) is attached to an M8x50mm bolt that I had lying around. On the lathe, I turned down the end of this M8 bolt to 5mm so the driver could be mounted on it. See pictures for details. The Hot-end is a cheap Chinese one that I don't even know the name of, but it works very well. For the dimensions of this Hot-end, see pictures. The stepper motor is a Nema 17 x 47mm. I recommend using a strong motor if you want to use 2.85 & 3mm filament wire. In the picture, you'll see a 42BYGHW811, but I'm currently using an SL42S247A (a bit more torque). As a driver, I still use an A9844 with heavy cooling and heat sink. For the main body, I had to add support material - see pictures for removal details. All other parts can be printed without support. I've printed all parts in PET-G 0.2mm resolution using a 0.4 nozzle. You'll also need: * 3x bearing 608z * 1x 11mm driver * 1X M8 x 50mm bolt or something similar * 1x hot-end * 2x snail house fan * 1X spring (optional, depending on filament material) * 1X nema 17 stepper * 1x kapton tape * 12X M3 nut * 4X M3 x6mm bolt * 9X M3 x 10 mm bolt * 3X M3 x20mm bolt * 9X M3 washer (optional) * 1X M3 big washer for filament guide * 8X M4 nut * 5X M4 x20mm bolt * 1X M4 x40mm bolt * 5X M4 washer (optional) After assembly, it's a good idea to put kapton tape on the bottom to protect the plastic from all the heat. This way, the plastic will last longer.