I'm a fabricator/machinist, with experience building/retrofitting CNC equipment.
I'm in a local makerspace and we stumbled on this 1988 Esab Signmate Sign Router 6'x10' over the summer via CL. When we purchased it was 100% working but the tribe as spoken to retrofit to a plasma table. We currently have a Hypertherm 1650 mainly for the robot. The frame is very rigid, and we'll be modifying for a water bladder build. The gantry itself weighs around 250lbs bare, comprised of steel and aluminum. I'm trying to accomplish this retrofit within modest budget.
It uses a rack and pinion for the X&Y Axis, though unforunately only one per axis. I plan on upgrading the old DC Brushed servos & 40:1 gearbox with 1kW AC Brushless Servos (2000RPM CONT/3000 MAX), with a precision inline plentary gearbox (<3arcmin, 10:1), aiming for 1000-1500ipm rapids. The AC motors seem a bit overkill, but for $105 shipped for new servo and lightly used drive I couldn't refuse.
I haven't quite decided on the control software but i'm bordering Mach4 or Linux. I don't have much experience with Linux but others at the shop have extensive experience developing for the linuxcnc community. I'm also considering the Nuron Lite for our THC if we do go the Mach route.
My first goal is to get the XY axis moving and calibrated. I'm hoping the servo and drives arrive by the end of the week. I've acquired a AIA 4" Actuator w/ballscrew & DC Servo that im currently benchtesting for the Z axis.
Original Drive system
X Rail bottom
X Rail Top