Intro: 5/16-18 Nut Holder for RepRap Z-axis
I made it at Techshop!!!
Here is a 3D printed coupling nut holder that I've used for the z-axis. 5/16"-18, 7/8" long coupling nuts fit snugly into this holder. It attaches to custom build x-axis carriage by using two bolts on its sides. This nut holder can also be used as a cheap cnc drive.
stl file is included.