Nerf Feet

thingiverse

I originally was going to print some of [these](https://www.thingiverse.com/thing:4725817/), but felt that the way they would sit in the rail was putting all the weight of the printer in to the arms of the model and not directly down in to the structurally sound part. So I first made a set of rival-h16-w26-1x-center-clip (that honestly ended up nearly being a clone) and put them on my printer. I later looked at my printer and though that it would look nicer if they were more square, so I whipped up a bunch of cartridge-style holders for two, three, and four balls. I didn't have any Rival balls and I couldn't find any data on their Shore durometer rating so I had no idea how much they'd squish and how many I would need. Maybe your printer is really heavy and you need a lot of them? I dunno, it was simple enough to make extended variants. The next day I found out I couldn't find the Rival balls anywhere around me, but I did find something I didn't even know existed, the Nerf Hyper balls. These were smaller (14mm vs 23mm) and more rubber than foam, and I felt they'd be a good alternative. Plus they were dirt cheap, a box of 50 was only $7. So I repeated the pattern, making a series of them that would fit on both 20mm and 40mm wide rails in various configurations. Some use M4 T-Nuts, some use a centering rail clip, some have rail Ts. There are parts for two, three, and five balls, in both 10mm and 20mm heights (in case you want a little extra lift). If you use the T-Nut version for the Hypers, those are hidden under the ball so button cap or socket flat bolts are probably best since they have the lowest profile I think. I printed off a pair of the hyper-h10-2x-w40-center-clip's to test the fit and if supports would be necessary (they're not, examples under makes). The Hyper balls stay in quite well, seem to give just enough squish. Since I put a lot of weight on my printer (two spools, attached tools, etc) I'm going to end up with the two I already printed in the middle and I've got a batch of four of the triangles for each corner on the printer now. Should be more than enough to distribute the weight and provide enough spring still to counter vibrations and whatnot. For the rail versions, I'd suggest printing them in their existing orientation so the rails are contacting the print bed, greatly reducing the needs for supports. You could also add an embellishment to the top layer with a quick color swap if you wanted to in this orientation, which is what I was initially thinking of doing but was too tired at that point to come up with anything fun.