Misumi 2020 Blind Joint Alignment Nut

I came across https://www.printables.com/model/115102-misumi-blind-joint-plate-for-2020-profile while dealing with some frustrations in assembling a printer, and while they almost worked in ABS, it wasn't quite there.  Did a quick redesign that took into account the strengths of FDM printing instead of trying to replicate the original part precisely, and the result works pretty well.

It's a tight fit, and you may have to fiddle a little bit to get everything started.  The piece is borderline single use, but that's to ensure that there's no load bearing plastic at the joint so these shouldn't require the extra hulk tension that some of the metal nuts do.  You will almost certainly hear the plastic split as you tighten these down.  

STEP included, modify to your heart's content.

The v2 adds a little more plastic around the bolt head, and opens the hole for the bolt to be a little less grabby.  Thread your bolt in fully until these are snug, back off ¼ to ½ a turn, and they should be about the right position.  They are press fit, and probably you'll shave off a little plastic as they slide into place.  In addition to the standard “flush” fit, there's an “inset” model, which allows for parts which may slot into the extrusion close to the blind joint. (As turned out to be the case with one of my printed parts).  As before, STEP is here in case you want to tweak.