Vertical Geared 3mm Extruder w/ Quick Release

thingiverse

Update 3/15/16: I've been fine-tuning an even more advanced version of what I uploaded initially, and it's performing incredibly well! I'm not expecting it to ever be completely perfected, but I've uploaded the current files in case someone wants to use them or tinker with them. If you have questions, leave a comment and I'll do my best to help you get it up and running on your setup. I've also added photos showing the extruder in various states of assembly and installed, along with some details on what you can expect from these pictures. The "installed" photos are current and work seamlessly with typical prox switches like those found on Printrbots. Please note that some of the images show older revisions which are mostly minor adjustments, but the mounted photos display the current versions in the files. The extruder body securely attaches to the quick release with no visible movement during printing. Removal of the extruder assembly is a breeze, done by simply loosening one M5 nut at the top clamp and pivoting the clamp up and out of the way once the retaining rod is removed. What I'm currently using features an aluminum plate for attaching a cylindrical prox switch, but if you prefer to print your own, you could definitely do that - just be aware it might not be as sturdy. The current recess in the bottom works great as a general mounting point for affixing a homing solution and/or fan mount, or you can leave it empty if you use a limit switch on Z, or simply omit any extra bits you'd need to create. How I Designed This Change List The most significant change was switching it from horizontal to vertical mounting, which shouldn't cause an issue but is useful to remember, especially considering one of the goals for the next adjustment (balancing) as it will shift the point the carriage is driven from, from below, to behind the extruder. Refer to the last two images to see the base plate and temporary quick mount. I reoriented the stepper motor to be more compactly positioned, keeping the hot end closer to the mounting plate to maintain minimal depth and hopefully achieve better balance and center of gravity. This might have potential drawbacks, but I'm unsure what they might be. Additionally, I made the hot end more accessible if you only need to mess with that component. It attaches with the same screws as before but features a separate clamping piece for removal of the hot end plus some built-in insets for nuts. I'm uncertain whether these would wear out or cause other problems, but it seemed worth mentioning. I also adjusted the spacing where the hot end mounts to accommodate an E3D V6 Bowden hotend. Further, I redesigned the large gears patterned area simply because why not? There were no functional changes made, except that the spokes are now too thin and might break or bend. Regarding mounting, the quick release mount setup features a notch on the bottom of the extruder body which fits into a corresponding cradle mounted to the gantry. The notch in the top will also align with a cradle at the top that pivots down onto the extruders top notch. A long bolt extending vertically from the bottom cradle mount up to the top pivoting cradle secures everything in place. Once the extruder is positioned and the top pivoting mount is rotated down, the long bolt will pivot into a slot in the top cradle mount and then a nut and washer are tightened down to clamp the extruder body between the top and bottom cradles. That's about it; feel free to point out any catastrophic oversights or suggest improvements!