Edit start/stop G-code on UM3 and Cura 2.3

[tonnesfn 0]

I'm trying to edit the start g-code on my UM3 to extend the initial extrusion of filament as I often find it isn't enough. I can edit the g-code on custom printers, but can't find a way to do it on the pre-configured UM3, and I don't want to use a custom profile as I'll lose some of the features cura has for the UM3. Are there any place I've missed where I can edit the start g-code for the standard profile UM3 printer?

[neotko 1,417]

UM3 uses a G280 gcode command that makes the initial purge.

To edit the amount of filament purge at the start of a print you should edit the printer_preferences.json that's on /usr/share/griffin/griffin/machines/ it controls everything and you need to access by ssh to your printer using root as user and ultimaker as password, to edit it. Also, if you edit it wrong the printer might need a reflash, and if you edit something that you shouldn't it might even make the machine not starting properly. Anyway after this warning, I edit it using 'vi' (google vi linux to know how to use it) and I change often the parameters to test things.

Easy? No. Can the start gcode modified on cura? not at the moment.

[LePaul 331]

I didn't see in Cura 2.3.1 where you can make any Start gcode as you could the old Cura

In my case, for my UMO, I like to extrude 15 mm of filament before the print begins.

What I do now is open the saved gcode with Notepad (assuming you use Windows) and manually edit the line, then save it. It's an extra step that's a little annoying, but works

[neotko 1,417]

I didn't see in Cura 2.3.1 where you can make any Start gcode as you could the old Cura

In my case, for my UMO, I like to extrude 15 mm of filament before the print begins.

What I do now is open the saved gcode with Notepad (assuming you use Windows) and manually edit the line, then save it. It's an extra step that's a little annoying, but works

 

Umo and um3 are parallel words. The purge command is a single gcode that readies the core. On umo is just a gcode sequence. Also you can edit your umo gcode start on the machine Preferences.

And ofc you could change the gcode manually to ourge more material, but that would confuse the machine prime sequence a bit. On S3D I make my own start sequences for um3. Not easy, but doable. Ofc Cura doesn't allow the users to have full control of the gcode...to make things easier...?

Edited January 2, 2017 by Guest

[tonnesfn 0]

I logged in over SSH and found two json files that inherited from jedi.json, where I found the prime_amount parameter. Is that the correct parameter to change if I want it to extrude more in the start?