When my friend initially talked about this we discussed the router style approach and that would work fine for a single project or two but he would like to sell the slabs after a little "value added work" that he puts into the pieces.
This calls for a semi-industrial solution. He has a machinist who he has a UO me (as opposed to IOU....
with so his thoughts are with a setup like the pictured router but more industrial and with automated tracking. The machinist would help to manufacture any specialized pieces or a whole unit.
He thought there are metal working machines like this. Anyone familiar with this type of automated table that could be converted to operate a "router like" head.