True story Daniel, I've got a mill and rotary table that I use when machining my oil cooler adapters, but I wouldn't bother doing discs for money, the time that it'd take to drill a set of discs properly would cost more than some people pay for their old bikes.
The pillar drill and scanned/printed pattern is probably the most economical, but I've seen some shocking jobs over the years, and one or two cracked discs due to people "swiss cheesing" their discs with insufficient metal between the holes, so be careful peoples, the life you save, might just be your own! Cheers, Terry.
