Man am I behind on documenting the mini lathe.
My original plan for the cross slide was to anodize it like Taig does, to prevent wear and galling on the aluminum-aluminum interface. I decided instead of dealing with nasty chemicals and temperature control (required for hard anodizing), to just remake the part out of steel. Steel machines much more slowly, but since I had already machined the part once, it went reasonably quickly.
Fortunately, Nick had a big chunk of steel which was very close to the size I needed:
The block was milled to size and top and bottom surfaces fly cut:
I forgot to take more pictures of it, but it looks pretty much identical to the original aluminum one.
I also attached one of the ballscrews to the carriage:
Bearing holders for the ballscrew were milled on the MITERS CNC mill. The ballscrew is retained radially by a single ball bearing, and axially by a pair of needle thrust bearings (not shown here):
Prepare yourself for the making the compound slide and machining a rack gear on a bridgeport in upcoming episodes of Tiny Lathe.