I've been meaning to document this a bit more, but have been busy lately and just finding the time to work on this let alone document the build has been tough. Anyways...

Lately my machine time has consisted mainly of cutting parts out of Garolite for a local speed shop; i.e. intake gaskets, throttle body spacers, etc. These jobs require a few hours of machine time, and I have some dedicated fixtures for the repeat jobs. I also process aluminum plate for another client, which also requires a lot of machine time and dedicated fixturing. This makes it tough for me to do some of the smaller work and prototyping that I enjoy doing. I also want to be able to take some of my work "on the road," like on-site engraving for local sporting events, maybe even some craft fairs. Plus I still need to fabricate some small parts for my aluminum mill/router and get that done as well.

I was able to obtain a whole slew of THK rails from a fellow guitar forum member during a fundraising auction a while back. All SHS15s, but all of them had 400mm rails. I was able to find some 508mm and 200mm rails pretty inexpensively. Since the rails I received had only one block each, I cherrypicked the best rails and paired the blocks; now I have a bunch of 400mm rails that I need to rid of.

For mounting the rails, I used Misumi extrusions, that have factory machined-flat surfaces. The surfaces are really nicely machined and very carefully wrapped. I used my favorite material, phenolic, for the machine frame and other parts. I also used 1/2"-8, 4 start ACME screws from McMaster Carr and dumpsterCNC nuts and threaded collars. I used 1/2" x 1-1/8" x 5/16" plain radial bearings with a very light preload to support the screws. Since I don't expect a lot of cutting forces (and certainly less than the 25lb rating of the anti-backlash nuts) I think I'll be fine with them. The bearings, like in my current machine, are integrated into the frame of the machine.

For electronics I will be using a G540 box with 24V psu, and SmoothStepper. Motors will be Danaher 200in-oz NEMA23s.