Homebrew PCBs

David McNab wrote:
> If you've got any constructive suggestions for evolving the mechanical
> design to something better, using only easily-available materials and
> non-specialised tools/techniques, I'm all ears.

Unsure of what you consider easily available but again
I'd recommend one of the many tooling suppliers.  The
latest Enco flyer has their perpetual "sale" on drill
rod, cored bronze rounds, and acme threaded rod and nuts.
Depending upon scale I'd hazard the bill of materials
for a basic XY set of ways to set you back about $10-30.
No affiliation with Enco other than they get far too
much of my money.

I don't recall if you have access to machine tools but
for such a project even use of a small lathe will not
only make the result more accurate but easier to
accomplish.

-- 
uhmgawa@...        www.gnu.org