Recently, Prusa Printers announced their upgrade to the MK3 printer, the MK3S. The upgrade is a total redesign of the extruder and includes a new filament sensor mechanism that is much more reliable for only about $20. So when they went on sale we picked up a few kits to upgrade our own MK3 printers and gain the new benefits of the MK3S. The first step to preform the upgrade is also the most difficult, print the parts. We printed a few sets of parts and even though nothing changed between prints the tolerances would vary from too tight to not even close. This ended up taking 3 or 4 attempts but eventually we got parts that worked. I pulled up the very helpful upgrade guide and got to work disassembling the extruder and building up the new one. The process was very straight forward and aside from a couple fit related issues I didn’t have any problems following the instructions through to the end. With the upgrade finished I flashed the newest firmware for our printer and began the calibration process to get it back up and running. For this little build I also made a nice time lapse video of the process so enjoy!