skip layer height?

tekstyle

I was wondering if there is a way to add to Cura or Slic3r a before layer change gcode that will skip the layer if it is not above a certain layer height?

I am experimenting with a way to save a failed print in the middle of a print while the print is still stuck to the bed and hasn't shifted, moved, or pop off. scrolling through the gcode in notepad and deleting the first half of the file is very tedious, hence the search for an alternative.

Phaedrux

@tekstyle said in skip layer height?:

scrolling through the gcode in notepad and deleting the first half of the file is very tedious, hence the search for an alternative.

I would just reslice the object but first either cut or drop the model below the build plate so that only the remaining portion of the model is sliced. Set to 0 bottom layers and slice away. Then you only need to customize the start gcode and ensure Z0 = the top of the print.

tekstyle

@phaedrux
how do you do a start gcode where z=0 is the top of the print? even if i set the start gcode to lets say z=5, it would still invoke a G1 Z0.xx Fxxxx at the start of the print. I don't think it would be wise to invoke a g28 command even for a delta. perhaps you mean set the Zprobe offset manually to Z=-5mm?

what about if I started the initial layer at the height of the failed print? so initial layer z=5.

I assume I would need to check the log file in the sys folder to determine at what Z height the print failed (either due to heater fault, or filament sensor, are the only possible known issues I can think of).

Phaedrux

Either set the Z height manually before starting the print and remove any G28 from the start gcode, or change the M558 probe type to P0 so that it lets you set it manually with a jog dialogue.

@tekstyle said in skip layer height?:

I assume I would need to check the log file in the sys folder to determine at what Z height the print failed

If possible use a ruler or caliper to get a rough idea and then examine the model in the slicer to try and match the features.

tekstyle

@phaedrux

thank you for the tip. I think you are referring to using the start gcode as a macro to change the Z=0 to the print failed height as the slicer will still "think" that is z=0 and generate the gcode file with the first layer .3 or .2mm above z=0.

Phaedrux

Not necessarily in the start gcode. I just mean before you start the print. So you could manually move the nozzle to just touch the top of the print and then use G92 Z0 to set the height.

dc42

@tekstyle said in skip layer height?:

I was wondering if there is a way to add to Cura or Slic3r a before layer change gcode that will skip the layer if it is not above a certain layer height?

I am experimenting with a way to save a failed print in the middle of a print while the print is still stuck to the bed and hasn't shifted, moved, or pop off. scrolling through the gcode in notepad and deleting the first half of the file is very tedious, hence the search for an alternative.

Did you pause the print when it went wrong? If so then you will have a resurrect.g file in /sys that contains what you need to restart the print at that position.

A quicker way than editing the file is to use the M26 command to set the file offset that you wish to start at. To find the file offset, open the file in Notepad++, put the cursor at the start of the line where you want to start, select "offset", and read off the "you are here" value.

tekstyle

@dc42

do I need to do anything so that printer will generate a resurrect.g file after it pauses? How would I start the print again? do I just run the resurrect.g file like I would with any macro file?

for the M26 method, does it require scrolling through the million lines of gcode while inside notepad to find the start of the line where I want to start?

Phaedrux

https://duet3d.dozuki.com/Wiki/Setting_up_to_resume_a_print_after_a_power_failure

tekstyle

@phaedrux

thank you all! this article will be very useful!