Very nice. It seems to machine Al just fine for most uses.
I particularly like the raised side rail design - that makes for a very rigid upright vs the risk of wobbly uprights on a moving gantry.
Is there a reason that you had to make your own circuit board to pull it off - that is a leap of faith for me.
It looks like there was some cutting fluid being dispensed, was that you or does your machine spray some before the cut ?