A resolution of .004" is probably pretty good for a
particle-board-and-drawer-slide machine. If you want the fun of making
your own cartesian robot or just want to non-critical work like engrave
signs. For PC Board work, I'm pretty impressed with the Zen Cart 7 by 7
machine:
http://zentoolworks.com/product_info.php?products_id=74Check out their user videos and Youtube for some good examples of
routing PC board with a .1mm cutter with sufficient accuracy for
double-sided boards. Not perfect, but it looks pretty good for the
price, and the PVC frame and actual linear bearing slides will be much
more precise and dimensionally stable than anything that can be done
with hardware store components. I also like that it's an engineered
system rather than a hodgepodge of whatever was on sale on eBay at the
time. Anyone using one who can provide some first person feedback?
73, Bob W9RAN