How to build a Custom CNC

[DonRotolo]

Maybe 10 years ago, Nuts & Volts had a mult-=part article on building a CNC 3-axis mill for about $400 (then). The XY table used 2 pairs of ball-bearing drawer slides (the good kind, with no play) and a dremel as the cutting tool, like this one.

Remember that a dremel is somewhat limited. Don't expect to cut aluminum with it, at least not quickly.

Regardless, definitely a project worth considering. The hardest part is the stepper driver, next is finding software for that old PC so the parallel port can be used to drive the motor driver. You can buy pretty good lead screws for not much more than the 1/4 inch all-thread the article suggests, and end up with 0.001 repeatability on 0.0005 accuracy.

If you attempt this, just think about what you're trying to accomplish, and don't cut corners where it matters. X, Y and Z must all be perpendicular to each other - perfectly. No play or wobble, in the lead screws (use plastic nuts, they last forever and have no backlash), or on any of the axes. Big is good, but too big is bad, becuase you get wobble. Why does that bridgeport weigh a ton?

Don