gcode model help pls

Ok, I have a model I want to print, Slicer has interpreted my wishes with the settings I have made, but there is a problem, the bottom of the model somehow got sealed all the way across… by another program. So I edited the G-code and got rid of the base I didn’t want, I set the first z height to 0 and the first layer prints fine, Yea!, but when the second layer prints it is at 8.880 mm up off the bed and of course this is wrong, I went through the Gcode and the rest is the same, above the bed, not from the bed up.

Is there a way to set the gcode to just start at the 0 bed height regardless of the next z- command line? So that it would print from that point in the model and just progress up?

Cutting the base of the model off in G-code is much easier than using the many faulty modelling programs out there that put false bottoms on all my models when they cut them or they leave holes in the solid model. The Slicer output got me past that nonsense, but now my model is 8.880mm above the bed, I may just find a platform I can adjust to meet this requirement if a simple software solution doesn’t present itself.

help, thanks in advance.


All of your Z coord in gcode are offset 8.880. Except the one layer …?
Then you have some geometry you’ve missed in your model. Maybe one plane leftover
If that should be the case just delete the extra

What happens if you remove that first layer in gcode and try to print? Will it repeat the offset?

I set the first layer as 0, the gcode generated by slicer after the bad stuff on the model is removed is 8.880 mm up off the bed, so if I delete that first layer you think with an offset I can get it to print the 8.880 layer as the first? what is the code for that?


I don’t know that such code exist. More like you would have to open gcode in txt and manually look into Z coord. Use ctrl+F to locate… in that text file you can see what are Z coord of your first and all other layers. For start…

Still, correcting the model in 3d programs is my way of doing things. I use combination of 3ds max and netffab cloud. When I wrap it up in max, I upload it to netfabb for a ‘model repair’

tried that, like I said, I edited the bad parts off the bottom of the model, now I want to set the “0” layer to 8.880mm off the bed. I’m looking for a solution for that, does Z offset do this?

When you “edit bad parts off”, what happens to the defined planes in your model?

Are you redefining the planes so that when you create your stl file there’s a clear origin, plus an X Y & Z axis that are not floating in mid-air somewhere due to the “edits” you made?

Sorry for asking what might be stupid questions…I guess I really don’t understand what you’re trying to do.

I am trying to use the edit G-code function of Pronterface to remove unwanted layers from the bottom of my model, and afterwards print the model. I’ve tried cutting it in several programs but can’t seem to get a good edit, in G-code when viewing it, I can see that the unwanted layers have been removed, but now the print is up off the bed, I just want it to 0 out and print after editing it.

If you use slic3r, there is a feature that allows you to set different layer heights at configurable Z heights.
You can set the layer height to be zero for a section of the model. This effectively makes that section vanish. I have used this to remove the bottom off some parts I have printed in the past.

Cura supports this as well, under:

Full Settings > Advanced > "Cut off object bottom (mm).

Cura- LulzBot Edition can be found here: https://forum.lulzbot.com/t/cura-lulzbot-edition-test-packages/934/1

Thanks the cura slicer works for removing the bottom and being able to see what you are doing to the model in 3-d, I’d recommend that software for this ability to remove the bottom from your model, if uneven or unwanted. Thanks again. :mrgreen: