Edit starting G-code for a glass plate - Nozzle cleaning

Bambu Lab X Series
1

Hello everyone !

I’d like to know if anyone knows how to properly edit starting g-code (I’m looking for the nozzle cleaning routine, done at the back on the plate, scraping it).

My bed is too warped for my liking, and I had a spare bed assembly. I scrapped the magnetic sheet and silicone glued a glass plate on it. But the glass plate doesn’t have an extra space for this nozzle cleaning routine and it would damage it (i think) to change the place it happens.

Is it possible to remove this routine and retain the full functionnality of the bed levelling sequence ?

If yes, what should I remove ?

Thanks for your answers,

Happy printing.

1 Like
2

It should be possible. But I do not know how your glass plate handles the impact of the normal/necessary probing with the nozzle.

The code block responsible for the hard wipe:

;===== wipe nozzle ===============================
M1002 gcode_claim_action : 14
…
G0 X135 Y253 F20000 ; move to exposed steel surface edge
…
M106 S0 ; turn off fan , too noisy
;===== wipe nozzle end ================================

No code block = no hard wipe.

Side note: Features relying on the camera or lidar very likely may not work with glass…

3

Thank you for your reply. I actually got to this block but thought that maybe removing it would cause issues…
I’ll try to play around with this soon. Thank you.
Side note : I don’t want to get rid of the wiping action done at the nozzle wiper near the chute. Would removing this block also remove this ?

Thanks.

4

The remaining lines of the code block right above should still be sufficient for that, they read:

…
G1 X70 F9000
G1 X76 F15000
G1 X65 F15000
G1 X76 F15000
G1 X65 F15000; shake to put down garbage
G1 X80 F6000
G1 X95 F15000
G1 X80 F15000
G1 X165 F15000; wipe and shake
M400
M106 P1 S0
;===== prepare print temperature and material end =====

→ Which is a normal wipe on that small silicone wiper.

But of course, without a hard wipe it now is your responsibility to have a somewhat decently clean nozzle.
What is lost, is the reduction to 140°C to probe the bed. But you’re probing a glass bed and the plastic will be softer at elevated temperatures.

5

Thank you for your replies. I’ll do some small scale tests on a normal heatbed and swtich when I’ll have satisfactory results.

6

Hi there I’m very late to the party on this one, I’ve never tried to edit the G-code before, I find myself in need of a profile that removes the wipe altogether and ideally doesn’t create a purge line. I’m not overly keen to delete lines and just set it off. Did this work for you? and does removing the line have any ill effects on the start up sequence?

7

Wow, great way to make your printer worse than it originally was.

Float glass is almost certainly not going to be flatter than the original bed, and has a lot of other shortcomings as well. There’s a reason printers stopped using glass like…8 years ago already.

I would have put a dial gauge on the head and then if truly bad, done some shimming or shaving of the bed to fix the issue but that’s just me.

At the end of the day, your printer just runs gcode. You can change any part of the code to do whatever you want - as long as the printer’s hardware can support it.

Deleting the wipe across the tip of the bed is no problem, and I’d suggest checking out a thing called “Steinwipe" which is a better nozzle cleaning option and some gcode modifications you may find useful. You could also write a preprocessing script to run after you slice a model that takes the particular lines out each time.