Splitting G-code into multiple processes

[OneOfPunx 0]

Hi,

Does anyone know how is there a free software to do the same than Simplify3d can do?

https://www.simplify3d.com/support/articles/different-settings-for-different-regions-of-a-model/

 

I would like to split the sliced code into multiple pieces so that i could shot down the printer and resume the print when ever i want.

 

I know that i might have some issues with material shrinkage and and bet to cold, but i would like to still try this with PLA which should work at some level at least.

 

So basically i would like to 

1.print the first part  with first GCODE-file

2. park the hot end up left so that it won't foul with the print if it comes from 0,0,0

3. Shut down whole machine for a day or week. (All power off from bed and hot end.)

4.warm the bed / hot end.

5. continue to print the second part where the first one finished with a second GCODE-file.

 

 

[gr5 2,071]

I hope some other's answer this but here's a few points.

 

1) Shutting off a heated bed is a bad idea - for me my parts will pop off the bed if I do that.  So you would have to print on 'blue tape'.  An older technology that works quite well.  You have to clean the blue painters tape with isopropyl alcohol.  There are many other technologies that work as well as blue tape but the key is you need the heat off if the whole print or on the whole print.  You can't change that part way through.

 

2) Some printers have the ability to continue a print.  For example tinkerMarlin for the UM2 and more notably the newer Prusa firmwares (less than a year or so old) will even let you literally pull the plug, then days later plug it back in and have it continue.  It will not continue if the bed cooled too much in the mean time so... see point 1 above.  🙂

 

3) To continue you absolutely must re-home X Y and most importnat (for this discussion) Z.  UM2, UM3, S5, S3 printers all home with the bed farthest from the nozzle.  Perfect.  But many printers home with the nozzle touching the bed.  This might be fine for a tiny chess piece but for a print that takes up much of the print bed you could get a collision with your partly printed print.

 

4) You can do this gcode splitting by hand.  But it is a pain in the neck.  The first time I did it, it took me about an hour.  The second time 10 minutes.  I had to learn about the G92 command for the Extruder axis.  Splitting gets easier the more you do it of course.  But if you make one small mistake it would really suck.

 

[OneOfPunx 0]

4 hours ago, gr5 said:

I hope some other's answer this but here's a few points.

 

1) Shutting off a heated bed is a bad idea - for me my parts will pop off the bed if I do that.  So you would have to print on 'blue tape'.  An older technology that works quite well.  You have to clean the blue painters tape with isopropyl alcohol.  There are many other technologies that work as well as blue tape but the key is you need the heat off if the whole print or on the whole print.  You can't change that part way through.

 

2) Some printers have the ability to continue a print.  For example tinkerMarlin for the UM2 and more notably the newer Prusa firmwares (less than a year or so old) will even let you literally pull the plug, then days later plug it back in and have it continue.  It will not continue if the bed cooled too much in the mean time so... see point 1 above.  🙂

 

3) To continue you absolutely must re-home X Y and most importnat (for this discussion) Z.  UM2, UM3, S5, S3 printers all home with the bed farthest from the nozzle.  Perfect.  But many printers home with the nozzle touching the bed.  This might be fine for a tiny chess piece but for a print that takes up much of the print bed you could get a collision with your partly printed print.

 

4) You can do this gcode splitting by hand.  But it is a pain in the neck.  The first time I did it, it took me about an hour.  The second time 10 minutes.  I had to learn about the G92 command for the Extruder axis.  Splitting gets easier the more you do it of course.  But if you make one small mistake it would really suck.

 

Big thanks gr5 for quick reply. And really good points.

1. That is a good idea. Ill have to buy that tape. It seems also that for example PLA can be printed straight on ABS bed without heated bed as well. Have to try that as well.

https://www.youtube.com/watch?v=ls2m7F-d42s

 

2. Sadly I think there isn't this feature available for Anet A8 printer. Only pause and continue if the power has not been turned off. Also the head bed must be turned off manually. I would like to turn everything off.

 

3.I'm planning to use this trick of course with some bigger and more complicated jobs. Any idea can the home position be edited form somewhere? so it would always start as high as possible for example.

 

4. This manual editing of the Gcode sounds quite easy and that was actually the reason why i was curious why it is not as an standard feature of slicer applications.

It could be relatively easy even to do excel macro in VB for this to split the code once sliced.

Actually that might be the way to go with this one if no app can do it.

It would be nice though to see the parts in visual 3d of the slicer tool

 

 

[gr5 2,071]

You don't purely split.  You have to worry about the extruder position.  Say you have printed 3 meters the extruder positions will be something like this:

 

G1 X10 Y20 E3001.71

 

(3 meters and 1.71mm)

 

As you can see if that was the first gcode then the first thing it would try to do is extrude 3 meters of filament.

 

But you can use the G92 command which says "this is your current position".  Like this:

 

G92 E3001.71

 

That above line tells the extruder that it is now at the 3 meter (plus 1.71mm) position so when it goes to do the G1 it won't extrude 3 meters of filament (and grind it to dust as it extrudes too fast).

 

Also you need to keep in the code that primes the nozzle.

 

You have to keep the home commands (G28).

 

Homing position can not be changed as it's done using a limit switch somewhere.  So it matters where the homing limit switch is for Z.  If your part is far away from the 0,0 corner of your printer (front left) then maybe it's okay to home there?  Or maybe not - maybe the gantry of the printer will hit the part?

[OneOfPunx 0]

Good points mate. 

 

After little googling i found these which might help me... lets see

https://reprap.org/wiki/Mulitcolour_printing_with_one_hotend

https://www.youtube.com/watch?v=Rh7VmjOLo0I

 

The idea with the excel was quite the same than the second link shows with cura, but the file would just be splitted into two.

[OneOfPunx 0]

Actually there is a even better tutorial related to this editing of Gcode

 

https://static.shoplightspeed.com/shops/608811/files/008600801/restarting-a-stopped-print-tutorial.pdf

[GregValiant 1,116]

I have written an Excel interface I use to talk to the printer.  There is a section on print recovery that can generate a script (that can be run from within Excel) to re-start a print from any point in a file (using the Byte Offset).  So long as your print isn't in the way of the auto-home position it will work.

I'll put it and the instructions up if you would like.  If you know some VBA you alter the code to suit your needs.

There is a link in the file to download a trial version (freeware) of SComm32.ocx that Excel will need to communicate through the USB/Serial port to the printer.

I use hairspray as an adhesion assist.  Sometimes I have to use an air hammer to get the print off the glass.  Other times it pops right off once the glass cools.  It isn't consistent enough to count on to hold a print while cycling from hot to cold to hot again.

[geert_2 556]

Another option that might work, is printing parts separately, and glueing? You are going to see the split lines anyway when you abort and restart a print. So glueing might do as well? For alignment you could make an extrusion on one part and a mating indentation on  the other part.