This is just the same thing as the original but done in SCAD so I could make an SAE version and tweak sizes. BTW it worked great for me.Also the coupler has two nut and two screw holes in each piece so they're all the same, just print 4 of the same thing.The X end in the photo exhibits wobble and a lot of other issues that I've now pretty much eliminated.As with the original, use 10-24 rod and nuts (or something else if you live in metric land). I think you really need to have a bottom bearing to take the load, but I think that's true of the original rod as well. A washer is probably advisable under the two locked nuts on the bottom.