Flexion HT Extruder for the Prusa i3 MK2S

thingiverse

Version history: - **v2.0 - Extra Chub** - March 9th, 2018 Changes and fixes: - Self-tapping fan screw holes no longer require incredible strength to screw into. - Improved alignment and tighter tolerances for mounting the stepper and extruder make it easier to assemble. - The overall strength and rigidity of the design have been improved at a slight cost in print time. - Better cable management options include a slot for a zip tie to hold stepper cables securely in place. - Even better thermal performance is achieved with a fully ducted heatsink that forces cold air from beneath the heatsink, over its cooling fins, and out of the way of the print head. - The blower fan nozzle height has been adjusted for better airflow aiming at the area directly beneath the nozzle. - Y-axis print area loss has been reduced to 10mm. - **v1.0** - December 19th, 2017 Initial release IMPORTANT: *The Prusa/E3D hotend cartridge thermistor is not compatible with the Flexion hot ends. However, a [NTC 3950 100K Thermistor](https://www.amazon.com/Happisland-Thermistor-Wiring-Printer-Heatbed/dp/B01N4KY6TR/) can be used as a drop-in replacement without any issues.* This design provides a complete extruder and hotend holder for mounting a Flexion or Flexion HT on i3 style printers compatible with the Prusa i3 mk2/s. No special hardware is required, and you can reuse fasteners from the old extruder body. I've aimed to make this feel as natural to the mk2s as possible, allowing you to use the original fan nozzle. It mounts on the stock x-carriage without altering or swapping out any parts, except for the extruder body and cover. The convective paths for air cooling have been carefully planned to ensure access to the full temperature range of the Flexion HT hotend, even when using PETG. There is one caveat: you will lose 12mm of build area along the Y-axis due to stepper motor clearance issues on the extruder. To compensate, see the final step at the end of this page/assembly guide. This design is compatible with both regular Flexion and Flexion HT upgrades. It's designed for single extruder use only and is not suitable for the E3D version of the Flexion. If you're using a **Noctua hotend fan upgrade**, feel free to continue using it – they should be fully compatible with this new extruder design!