"Jim Wilkins" wrote in message
...
"rangerssuck" wrote in message
...

...I'm starting to think that I really could do this with an x/y
positioned dremel and a two-position z axis.

I estimated that I could build the mechanical part from surplus
Thompson rod etc without too much difficulty. In college I built a
wooden animation stand with similar x, y and z motions for a
film-maker.
https://en.wikipedia.org/wiki/Animation_stand

The snag would likely be having to code design rule checking to
ensure that the cutter never violated the overlapping exclusion
zones of all nearby design and drafting features. You couldn't just
outline each line segment independently, they are meant to be
created by an additive process that allows them to overlap while
milling is subtractive. It was hard enough to properly define all
the widths and clearances in the pad stacks when the program did the
checking, although I had more layers to attend to on a board with
inner planes, solder masks and silkscreens.

--jsw

I faintly remember another technician showing me a board on which the
T-Tech had fully outlined each track segment, resulting in arcs and
circles milled through the tracks at every pad, corner and junction.
He may have drawn the tracks as overlapping graphic lines instead of
named electrical nets and the compiler didn't recognize that the pads
and track segments should be left connected.

I quit planning how to build one when I realized that the programming
effort to check spacing and detect all overlap conditions would more
than nullify the time saved not waiting for etched boards.

--jsw