I am having issues with my scarf seam causing stringing on a P1S with bambu matt black PLA. I’ve tried lowering my printing temp to 220 and lowering the outer wall acceleration speed, both have not helped. The filament is flow rate calibrated. I was thinking about adjusting the scarf start high, but I’m not really sure what that does. Any help on what settings to try would be great.
Ring Test.3mf (41.0 KB)
Looks like moist/new filament. Give it a thorough drying.
If it still happens after that, consider enabling “wipe on retract” in the filament settings and maybe increasing retraction speed.
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I just tried a brand new spool that I dried for 12hrs with the same results. I turned on “wipe while retracting” increased retraction speed and distance, all with no improvement.
Have you tried calibrating reattraction using Orca Slicer?
Another analysis you may want to try is to uncheck all of the line types except for retract and see if the locations of the retraction in the preview aligns with the locations of the stringing in your physical model. If it doesn’t, it’s another issue.
Ah. I would have bet that would have been it. My apologies.
I addition to @Olias advice, you could try to perform a diagnostic (i.e. partial) print with an aligned seam rather than the scarf seam. That may not be what you want but it’ll help narrow down the root cause.
There’s also the potential for a symptomatic treatment rather than hunting down and eliminating the root cause. Fine stringing can be removed using a lighter.
Edit: I am afraid that I do not have much experience with troubleshooting seam settings. Scarf seam has worked for me since its introduction. Even when reaching very low local flow rates when using “seam around entire wall”. Nevertheless, here’s the link to the wiki which may be better at explaining the multiple settings and helping to troubleshoot.
Don’t have much to add about preventing it; but minor stringing like that can be removed in just a couple seconds.
Heat gun or a butane torch to ball up the strings.
Wipe firmly with a dry cloth to remove the balls.
Done!
I’ve never used Orca Slicer. I’m relatively new to Bambu printers. I do recall reading something about how orca slicers scarf seams is much better than bambu studio. So maybe its time I make the switch and give that a try
I completely forgot about the lighter method for stringing, thanks to you and @Bullocks for the reminder. That made it 80% better.
I did end up figuring out the issue. I had seam position set to “back”, when changing to “aligned” it solved the stringing problem. I’m assuming this has something to do with the scarf seam location being set to the same spot on the inner and outer walls with seam position set to “back” vs with the seam set to “aligned” the seam on inner/outer walls are in different locations.
New problem though, its now putting the seam in a very obvious spot on the outside. Using the seam painting feature moves both the inner and outer seam to the same location, which causes the stringing to happen again. I don’t care where the inner wall seam is at, only the outer. Is there a way to control the seam position independently from the inner/outer wall?
Hi @VaporiZe ,
Many thanks for reporting back 
I am glad that you found a very good indication of the root cause although I have to admit that I do not fully unserstand the physics behind it yet. 
Your observations indicates dependance on the scarf length. I am not sure if painting two seams, one insides, one outsides will give you better control, or if it will be overridden by other settings (such as scarf length).
A further hint came from Microsoft Cockpit and a subsequent wiki review. Aparently, increasing the scarf start height can be a measure to improve the stringing.
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PS: Orca is very, very similar to Studio but with more options. There’s a caveat in that nowadays, we can only use 3rd party slicers conveniently by putting the printer in LAN mode and enabling the “Developer” mode.
If you’re new to this ecosystem but not necessarily new to 3D printing, it may help to understand the pedigree of these slicers. I won’t go all the way back to the beginning of the RepRap DIY era and the granddaddy of open source slicers, SLIC3R but know that PrusaSlicer is based on it and Bambu Studio is a fork of both PrusaSlicer and SuperSlicer.
The point here is that there is no harm in having both slicers on one machine and you’ll find that Orca has a whole lot of additional features - including scarf joints - that are intended to improve quality of life for the user. Things like the caliper, the CAD cube for navigation and so on are all Orca innovations that Bambu quietly reincorporated in BS. They give credit on their Wiki and it should be noted that two years ago, when they were hungry for new customers, they even recommended Orca. That relationship chilled quickly with the introduction of the draconian and anti-competitive “Bambu Connect” in January of this year. The community cried foul, and Bambu’s response was to gaslight users into believing they were doing the honorable thing by giving us this feature nobody asked for. The rest of us called ■■■■■■■■.
Since all of this is based on open source, Bambu was obligated to publish their source code. The folks at Orca - actual 3D printing enthusiasts - noticed that many features, including scarf seams, were not carried over. Over the last two years since the launch of Bambu Studio, the Orca team has been restoring the functionality and polish that Bambu stripped away. They’ve pulled from Prusa, SuperSlicer, Cura, IdeaMaker - you name it. So saying that “Orca’s scarf seams are better” is technically true, but it misses the bigger picture: Bambu wouldn’t have any of these features without Orca, and even then they only implement enough to serve their real agenda.
Let’s stop pretending Bambu is innovating here. Their slicer isn’t built for community improvement - it’s engineered to funnel users into a closed-loop system. Their moves over the past two years make it clear: they aren’t trying to build the best slicer, just the most controlled one. “Close enough” is all we get, and that’s by design.
Ideally, we all want our prints to look perfect right off the plate. Calibration is key, and I’ve long been an advocate. That said, the Chinese business philosophy of “Chabuduo” (差不多) isn’t entirely without precedent. Back in my grandfather’s day, we called it “Good ol’ Yankee Ingenuity” - but the resemblance ends at the surface. Chabuduo stops at “good enough” to sell the product, then walks away. Yankee Ingenuity meant solving real problems in the field. U.S. air crews won battles in the Pacific by retrofitting aircraft on the spot - often making them better than when they left the factory. It’s the same mindset we apply when we mod our printers - a practice Bambu clearly resents. Chabuduo is just corner-cutting with branding, and Bambu is no stranger to it.
An open secret in the community is that you can often burn off stringing without recalibrating anything. I’ve used both a heat gun and a jet lighter. Practice is key - it only takes a quick pass - but the finer the stringing, the easier it is to clean up with heat.
https://www.amazon.com/s?k=jet+lighter
I have one similar to this near my accessories (like glue sticks). Mine was $9 and didn’t include the base - so I printed one. 
https://www.amazon.com/s?k=heat+Gun
The one on the left I bought years ago for heat-shrink tubing. Still going strong. I see the blue model now sells for under $10. I used it until I upgraded to a jet lighter.
I downloaded Orca and did the print with the seam set to “back” and it caused the stringing issue again. I don’t really understand why the seam has to be set to “aligned” with scarf seams to get a clean print, but its the way it is.
