I spent some time looking for a cheap surface plate to use as the machine base, but couldn't find anything that was cheap enough and not 200 miles away. So I went on the scrounge to see what steel I could find. I came back with some 80 x 80 x 3 box (again thinner than I would have liked) and some 40 x 40 x 5(?) which would do just fine for the Y axis.

I cut a couple of lengths of the 40 x 40 and squared them up the best I could with files then wrestled them into the vertical slide on the lathe to clean up a slot for the leadscrew bearing mount:




The bearing mount itself needed 3/4 of a hole boring in it



The mount is bolted to through the 40x40 so that it's angle can be tweaked to be truly square to the Y axis leadscrew. The thrust bearing is a standard BK10 part from China. (I changed the standard ball bearings it came with for some angular contact ones.)




With the 40 x 40 spacing set, I cut out the 80 x 80 section to suit. The area between the 40 x 40s also needed to be cut away and plated over to clear the leadscrew and ball nut.




I added some gussets to try and brace the 40 x 40 rails to the bottom corner of the 80 x 80




Before welding the mounting flanges for the gantry feet I put the gantry in position and set it square and level to the base



Everything will be squared up properly when the thing is finally assembled, and the flanges bedded in epoxy, but I wanted to get it as close as I could at this stage.

The mount for the Y axis stepper is bolted to the ends of the two 40 x 40 sections (I couldn't think of a better way of doing it).

I welded a couple of blocks into the ends of the sections to give something to fix the stepper mount to






And hacked a mount out of aluminium (wouldn't it be nice to have a CNC to do this stuff? )




I thought that the Y axis still looked a bit flimsy in the side-to-side direction so welded in a bit more bracing - trying to tie the Y rails into the gantry feet