Z-Offset after pause?

[separker 0]

I'm experimenting with printing on fabric, and trying the method of printing a few layers, laying the fabric over top, then printing more to trap the fabric in between. The problem is, the printer doesn't account for the thickness of the fabric, so the printhead sometimes. I see in the "Pause at Height" script there is a section for G-code after pause. Can anyone help me with what the code would be to have the print resume 0.5mm (or whatever the fabric thickness is) higher? Or, is there a better method to achieve this? Thanks!

[gr5 2,240]

There is a gcode to reset where an axis is.  For example if the Z is at 3mm above bed you can tell it to reset everything in that axis such that it should consider itself to be only 2.5mm above the bed.  This is G92 and G1 goes to a specific location.  I don't know if G92 accepts negative values for the S5 firmware so that complicates things slightly.  In other words you need to use both gcodes.

 

So right after the pause I'd go to a specific location above the shirt and then tell the printer it's lower than it things so it prints a bit high going forwards.  Example:

 

G1 Z10    (move Z axis to exactly 10mm above the glass)

G92 Z9    (tell printer that it's is now only 9mm above the glass (even though it's 10mm))

 

Going forwards it will print 1mm higher than all the gcodes say to print.  If you want to increase printing height (after pause) by 1.2mm then do G92 Z8.9

 

If you want to increase by only 0.5mm then do G92 Z9.5

 

Next problem - how to insert these gcodes into the file.  It's pretty simple.  S5 uses "UFP" file.  Rename that to zip and open up the zip file and look around.  There are only 5 or so files in the directory structure.  Extract out the file that ends with ".gcode" and edit that with a text editor (not microsoft word - a simpler editor) and look for the pause.  It should have I think "M1".  I think M1 or M0 is the pause.  I forget but there should only be one of those and also there will likely be some comments that say "pause" or something.

 

Add your 2 gcodes after the pause.  Put the gcode back into the zip file.  Print it.

 

There may also be an "add gcode after height" plugin?  I don't think there is but there used to be one for the older version of cura.

 

[gr5 2,240]

Once you get tired of editing the ufp file all the time you can write your own plugin.  I would edit the existing "pause at height" plugin but change the name of the files and such to "pause and skip up" or something.  Add a parameter for how much to skip upwards.  The coding change is pretty simple even for someone who has never programmed before (in this specific example as you aren't doing any loops or conditionals or anything - just adding some more commands immediately after the pause).

[gr5 2,240]

I would also consider keeping the fan off until after one layer has printed above the shirt.  If the print doesn't have overhangs or bridging (just a simple flat print only a few layers thick) then I'd turn off the fan completely.

 

I would also experiment with higher bed temperatures.  PLA softens slightly (like hard clay) at 52C and gets progressively softer as you go up to say 100C.  It doesn't melt until much hotter - maybe 150C?

 

So you can probably print fine at bed temps as high as 100C with fan off and get better bonding to the fabric.  Maybe.

 

Actually hopefully you aren't printing PLA but you are printing something flexible like TPU or ninjaflex or similar.  But the same advice applies: play with fan and bed temp.

[separker 0]

Wow, thank you for such a detailed response! I will give this a shot and see how it works. Much appreciated!