Occasionally, my P1S would pull the prime line printed at the front of the plate into the print itself. It was random, and somewhat annoying, and would require me to stay near the printer and grab the line before it got pulled all the way. I want to credit a user on Reddit (https://www.reddit.com/user/ZuperPippo/) for solving this problem.
In Bambu Studio, navigate to the Prepare tab.
Under Printer, select your correct printer/nozzle size. For example, select Bambu Lab P1S 0.4 nozzle. Click the small edit icon next to this.
Select the Machine G-code tab.
Find the line that contains: G0 X18 E15 F{outer_wall_volumetric_speed/(0.3*0.5) * 60}
And replace it with: G0 X50 E15 F{outer_wall_volumetric_speed/(0.3*0.5) * 60}
Use the save icon at the top of the window to save a new printer profile. I called mine: Bambu Lab P1S 0.4 nozzle - Fixed prime line
Repeat for each of your nozzle sizes (0.2, 0.6, etc.)
If you do a test print, you can see how/why this works. I wish I could inform the Bambu Studio team to incorporate this change going forward!
Yes - the prime line makes two passes. On the second (return) pass, this code stops before it gets back to the initial start position. So, the adhesion of the first pass remains intact. If you do a test print, you can see how it works - brilliant!
Thank you for this tip, it’s made a big difference! More often than not my P1S tries to drag the prime line and this fixes that completely. I just ran flow calibration and that doesn’t use the setting, so of course it tried to drag the line (note: I took the photo after pulling the line back)
Thanks for the fix. Worked for me as well.
My P1S dragged the prime line with it almost every time … pretty annoying, especially for remote printing.
Thanks for sharing.
This seems to work! My P1S didn’t always do this, had it a little over a year and it’s started mostly in the last month I think. But it’s gotten bad enough that this needs to be fixed, so thank you!
Thank you. I updated Bambu Studio the other day an realize that the new version had this same error. I was going crazy. Made this change and back in business.
I had a lot of trouble finding this (I’m still fairly new at this & had never modified a printer preset before). It turns out it only appears if you hover over the printer field (I’m not sure if this has changed since you originally posted). For future readers, it’s here:
Also for future readers, the line you’re looking for is near the end of the Machine start G-code section (currently at line 255 of 269 on the 0.4-mm preset):
Thank you so much for posting a solution to this very vexing issue that has plagued me for a few months. I have no idea why this started but suspect it’s something to do with a firmware/software update. This issue of shortening up the second prime line fixed my issue 100%. I tried the other side of the build plate, cleaned with dish soap, alcohol, all with same results. It wasn’t until I found this post that I was able to figure out a fix.
After editing the gcode, you can save the changes as a new nozzle profile at the top of that printer preset screen. “BambuLab P1S 0.4 nozzle - prime line” for example. Then you can select it when you want to use it.
Thanks for this fix - The purge line problem was driving me mad after fitting a new head due to a jam. Thought I’d really cocked things up! 