Optical Endstops for Anycubic Kossel The Anycubic Kossel is a great little delta printer. Like all delta designs, getting them calibrated can be tricky, especially if your endstops don’t have good accuracy and repeatability. The problem with inexpensive mechanical endstops is that they have a good bit of “slop” in the breakpoint tolerance. Optical endstops solve this problem and they will also help to improve the overall print quality. Parts list A detailed parts list, along with links to suppliers and additional design details, is available here. https://codemonkeyzero.com/anycubic-kossel-optical-endstops-upgrade/ Build notes The stock screws that attach the mounting bracket to the 2020 extrusion will need to be shortened slightly. All other stock hardware should work with no modification. I designed the holes in the parts to be tight so have a tap or hand-drill ready. You will probably need to sand or file the flags and do a little fine tuning here and there to get everything working perfectly. The fit for the endstops is tight, as you can see in the photos. However, the modification will give you a slightly larger build volume on the Z axis. Bonus! Experiment with moving your linear bearing rails up ‌higher on the extrusion before you commit and tighten everything down.