Once the frame and electronics are assembled, a careful first setup saves a lot of frustration (and foam). Take it one subsystem at a time.
1. Wire the motors
Connect each stepper to its driver channel. Get the coil pairs right (a wrong pairing makes the motor buzz/jitter instead of turning). Keep motor wires away from the high-current hot-wire wiring to avoid noise.
2. Wire the hot-wire circuit separately
Run the hot-wire supply through its MOSFET (switched by the controller's PWM/spindle output) with adequately rated wire and a fuse. Keep this circuit physically and electrically separate from the logic. Double-check polarity and that nothing is shorted before powering up.
3. Flash & configure firmware
Flash FluidNC (or GRBL) to the controller. For FluidNC, upload a config.yaml describing your axes, pins, steps/mm and limits. Start with motion only — leave the hot wire off until movement is verified.
4. Verify motion & direction
- Jog each axis a small amount. Confirm it moves the right way — flip the direction in config if not.
- Check the two towers move independently and in the same sense.
- Set conservative speeds and accelerations first; you can raise them later.
5. Calibrate steps/mm
Command a 100 mm move on each axis, measure the real travel, and correct the steps/mm (see Motors & drivers). Do this for X, Y, U and V independently.
6. Test the wire (carefully)
With the wire tensioned, power the hot-wire circuit briefly at low setting and confirm it heats evenly and the M8/M9 commands switch it. Have a way to cut power instantly. Only now try a slow cut in scrap.
7. First cut
Design a simple straight or rectangular cut in cncfoam.com, set "no homing switches" if you have none, jog to your work-zero, and run it slowly. Watch the wire stays straight; tune feed/temperature on scrap before doing anything important.