Bob La Londe wrote:

Is there any reason why the gantry has to move on a CNC router? Seems to me
you could get a lot more rigidity by moving the table along one horizontal
axis instead. Then just move your Z axis assembly along the gantry for the
other horizontal axis, but have the gantry solidly bolted to your table
base. I realize it will take up more room when working this way, but that's
no different than a mill.

Just thinking out loud.



No reason at all, heck, you can move the table in two axes and have a
nice rigid Z axis only gantry.

It all depends on what you want to build, both work envelope and
physical envelope, as well as the parts you can find on ebay or the
cnczone classifieds, of you want to spend new $$$ on.

They type of work you plan to do also significantly affects the design
requirements, i.e. routing commercial grade wooden signs requires a more
rigid machine than routing foam for lost foam casting.