Printed with Hatchbox PLA 25% infill. Custom designed "balls" for the 5/16 hex nuts. I also custom made a top bearing mount as I have an 600mm lead screw so needed the support for that. Easy to assemble however not a fan of trying to tap the holes on the ends as they don't go very deep without hitting the frame bolts. I think those could be done away with and extend the flange a bit more and add another spot for a t-nut and M5 bolt on the rail. All my hardware was purchased at lowes and I ordered the t-nuts amazon.
I custom made the balls which contain the hex nuts. These pop apart as I've put pry slots in them. They tighten up against each other so no need for adding washers =). I also custom made and designed the top bearing mount for the lead screw.