monoprice select / wanhao i3 fixed bed calibration

thingiverse

I really dislike the springs that come with this printer. They don't seem stable and my machine always goes out of calibration. There are caps available on Thingiverse designed to make them more stable, but they still lean. To solve this problem, I purchased 4-40 screws (even though the metric version is included, American thread is easier to find in the States). I mounted them the same way as the existing ones - by screwing them down and adding a nut underneath. Next, I pressed some 4-40 nuts into the knockoff springs (which are larger than the original metal ones with nice chunky knurl) and threaded one of them onto the knockoff spring, making sure it's facing up. Then I threaded another nut under the bottom metal bed. I started by lowering the bed, zeroed out my machine, and slowly raised the bottom nut while re-tightening the knockoff spring. If it wasn't close enough, I loosened the knockoff spring, turned the bottom nut a bit, and re-tightened it. Ideally, printing eight of these would make it easier to turn the bottom nut.