Hi All
I hope this is the proper space for this question.
Excuse the noob question.
I have searched for an existing advice and still continue with this problem.
My prints on the P1S and Bambu brand filament using stock settings result in the part having a frayed/stringy appearance where there are supports. It’s as if there should be a boundary layer that is missing.
I get this regardless of filament type.
I have tried the following edits to print parameters with no success.
Am i on the right track? I must be missing something obvious.
Thanks for the help
I’m using Tree supports and have tried these edits:
Global>Support>Advanced> Top Z Distance changed to 0.15 (from 0.2)
Global>Support>Advanced> Top Interface Layers increased to 3
Global>Support>Advanced> Interface Pattern changed to Grid
Ty for the image. It’s clearer what can be causing the hairy or stringy surface. Nevertheless, I don’t see if the support surface is solid and/or planar or has a hollow space within and/or an angle. In the case of a hollow, what is the solid region thickness?
Also, do you have AMS, and if so, PETG filament?
The support surface is planar, flat and not angled.
It has hollows only in so far as a tree support structure has gaps between the branches.
Yes, I use an AMS.
The filament is dried in a dyer prior to use.
This print behavior I have seen with all materials I have used so far - PLA basic, PLA matte, PETG and ASA.
It’s as if there is no skin on the underside of the part where it meets the support surface.
Do the print edits i mentioned in the first post make any sense?
Your prints and troubleshooting attempts make sense, but I still have doubts.
Great. I would say that the most promising solution is to use PETG for the support interface layer. This will reduce the space between the layers without sacrificing the support release. If it’s your first rodeo on using PETG as support material, BL will set your print setting automatically as soon as you define the support interface material, yet it’s worth reading and following: Printing guide for using PLA Basic and PETG HF for support | Bambu Lab Wiki
If PETG support is out of question
Assumptions from what I got from your description:
What I can see from your print is that the outer walls print well, and strings appear in the lower radius lines. If true, it means that the overhang walls printed well, but they fail, which may be related to the orientation that occurs at the bridges, i.e.:
A possible tweak is increasing the wall number in that region, eliminating the bridges. I.e. you can print all as an overhang wall, with the path following the radius, and less likely to not hold:
Besides this, your approach of tweaking the settings is correct, but if not successful, you can test methodologically; the parameters that influence are:
Bridge flow;
Thick bridges;
Bridge print speed;
Cooling;
Bridge direction;
Support → Top
Z distance;
interface layers;
interface spacing;
and many others as support types;
Of course, you should focus on the most likely ones and change one at a time, as you did (I guess). To avoid wasting filament, I would suggest making a smaller test file by cutting your model to use in tests, e.g.:
I also find it useful to mark the prints to remember which matches a specific test, e.g., use BS text to add a number, a marker at the end, or a label.
