12V 15A PSU. I panicked after ordering that I had ordered a 220V unit, but it turned out to be switchable to 110V. It gives out 12V and did not show any immediate intention to spontaneously combust.

z-axis lead screw

CNC shield and Arduino clone. The "Geekreit" CNC shield is a copy (not a clone) of the Protoneer 3.00 shield. A copy down to the silkscreen, which is really bad form. It comes assembled and with 4 A4988 drivers and an Arduino clone for $12. As one of the objects of this project is to keep the costs down, I'll use it, but a shout out to the folks at Protoneer for designing it. I think this board is pre grbl 0.9 I.e I need to swap pins 11&12 between the shield and the board.

This stuff all seems to work, after I figured out I needed to jumper the ENA pin on the shield to GND.

The little Nema8 motors get mighty warm, so I read up on current adjustment and cranked the Z way down. These are apparently easily melted, so some care is needed there.