Automatic raise/lower S4 Shelf
I use two S4s and space is tight on one side of the printer. I added a lifting shelf so that I can lift the S4 out of the way and then lower it to access the filament. This works in conjunction with having the whole XL on a sliding shelf. So, I slide the XL out from the wall, lower the S4 so that I can access the filament, raise the S4 back up, then slide the XL back in. It lets me be in very tight quarters with my other printer that shall not be named. I'll work up a write up on printables. It's not an ideal design, frankly. In particular, the shelf can rotate around the ball nut, so it doesn't stay as flat as I would like. There are a couple other things that I would also change. But, it works, was fun to design, and it's fun to use. Some of the ideas or parts may be useful to you.