Filament priming during heatbed warming?

I’m still learning so apologies if I’ve been hasty in creating this~
I start printing, it says it’s warming up the bed, and then the nozzle goes to the poop chute and just unloads abunch of filament. I’m sure it’s priming so it’s pressurizing the nozzle, but it seems super excessive. Everything is up to date as of today, but is there a way to turn that off or at least turn down the amount it primes while the bed is heating before doing the filament calibration and bed leveling?
Thanks very much!
If any creators are reading this, bravo, I feel like you just summed up the last 10 years of my life in 3 minutes with the automated calibrations lol, I’m literally amazed :slight_smile:

Priming is actually done with that line on the side, just seconds before the print starts.

What you see here is just the startup procedure that occurs before every print. It makes sure there is actually filament loaded in the hotend at all and that it has the color, which it is supposed to have. Lets say you finished a print in black and cut the filament inbetween the extruder and the nozzle. This way the extruder can eject the filament with a cold nozzle and lets you load a new color into the extruder while cold as well. When you change to white, it takes quite some purging before it will actually be white and this start code purges all the old color after heating up the hotend to make sure it is not mixed. After that it actually cools down and reduces pressure and wipes the nozzle on the back side of the build plate, so it is able to do bed leveling with the nozzle properly.

This also takes quite long.

You’re not the first one to notice that it is a bit excessive and the code that does that can be adjusted in the slicer (machine startup gcode).
There are alternative startup gcodes available online (i think I’ve seen something about that on printables). I think there should be a thread i this forum about it as well. I have not specifically searched for it, maybe you can find something.

When you use that quicker gcode you need to put in more care into your filament changes, when you don’t want to have mixed colors in the first layers of your print after a filament change. I usually change filaments with a cold pull on my P1P, which produces cleaner results (pulling PLA at around 75°C). There is a video from Bambu Lab that shows how to cold pull on YouTube, in case you’re interested in that.

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