Modify GCode to restart 3D Print

• Load GCode in text editor
• Find lines like Z0.*:

;LAYER:0
M107
G0 F8400 X9.53 Y-66.192 Z0.4

The first line with Z0.* is the initial layer height and would start the full print.

Now search for the line with Z=*.* where *.* is closest to the already printed height.

If in doubt, use the lower height (max 1 layer!) or the resumed print will not stick well to the part already printed. It is probably best to reduce the speed on the printer at the start to allow the nose to melt its way through the part instead of pushing it away.

Note down the extruder relative position E*.* before that line. Should look like this one (if measured height is 30.4 mm):

G1 F1500 E440.37857
G0 F600 X44.668 Y-41.761 Z30.4

Replace all lines between the first Z0.* line up to before the one with the current print height with the extruder initialization command "G92 E*.*". Use the noted value, e.g.:

G92 E440.37857

The new start (not counting initialization code) should now look like this:

;LAYER:0
M107

G92 E440.37857

G0 F600 X44.668 Y-41.761 Z30.4

Finally check for any lines in the initialization code before the Z0.* line thet use a Z value below the current print height (for nose wiping or similar, and remove them or modify the values to above the printed part. E.g from:

G1 Z15.0 F9000 ;move the platform down 15mm

To ~15mm above the print height:

G1 Z45.0 F9000 ;move the platform down 15mm

Save and start print with that gcode...