1. Generate the gcode using your slicer of choice.
2. Preview the gcode to determine which layer you wish to pause at.
3. Open up the gcode file in a text editor, and find your layer start. Simplify3D inserts comments at each layer, which makes this easy: "; layer 22, Z = 4.4"
4. Insert some gcode to raise the nozzle a bit and shove the bed forward, then pause the print:
Code: Select all
G0 Y200 Z10 F1200 M0
5. Insert your nut or whatever, and unpause the print to continue. Don't mess about too much, as there is an idle timeout in the firmware. It is helpful to thread the nut a little ways onto a screw to place it. Make sure it doesn't stick up above the current print layer or you could catch your nozzle. ABS doesn't want to stick to steel, so the next layer might be a bit messed up, but it should sort itself out quickly.