Bear with me for a moment, because I’m not sure how to describe this problem without just describing a part I’m trying to print.

I was designing a part today, and it’s basically a box; for various reasons I wanted to print it with all the sides flat on the print bed, but have bridges between the sides and the bottom to act as living hinges so it would be easy to fold into shape after it came off the bed. But when I got it into PrusaSlicer, by default, Prusa slices all bridges in a single uniform direction–which on this print meant that two of the bridges were across the shortest distance, and the other two were parallel to the gap they were supposed to span. Which, y’know, is obviously not a good way to try to bridge the gap.

I was able to manually adjust the bridge direction to fix this, but I’m kinda surprised that the slicer doesn’t automatically choose paths for bridging gaps to try to make them as printable as possible. I don’t remember having this issue in the past, but I haven’t designed with bridges in quite a while–it’s possible that I’ve just never noticed before, or it could be that a previous slicer (I used to use Cura) or previous version of PrusaSlicer did this differently.

Is there a term for this? Are there slicers that do a better job of it? Is there an open feature request about this?

Basically just wondering if anyone has insight into this, or any suggestions for reading on the subject.

Thanks!

  • Einstein@sh.itjust.worksEnglish
    2·
    16 hours ago

    Have you tried rotating the pattern of the infill or top/bottom 45 degrees? I don’t known if bridge lines are completely separate from those or if they are considered part of the infill or top/bottom, I was thinking one of those settings might work though. I know you can rotate the infill and top/bottom pattern in cura.

    • monotremata@lemmy.caOPEnglish
      2·
      15 hours ago

      I’m using PrusaSlicer, and in PrusaSlicer there is a specific setting for this, which is called “bridging angle.” But my point is that bridges are already specifically identified by the slicer as a specific category of print area needing specific settings, and in this case it should be possible for the slicer to choose an optimal bridging angle on a bridge-by-bridge basis, rather than requiring the user to choose a single global angle. You’re right that it would be less catastrophic for the bridging to be 45 degrees off than to be 90 degrees off, but it’s not obvious why this should be a global setting at all, rather than tailored to the needs of the local geometry of the bridge. It could even be something fairly simple, like just drawing lines parallel to the perimeters of the bridge, similar to what “concentric infill” does. I haven’t really looked in to what the best way to implement this feature would be, I’m still at the point of trying to work out how to even describe the issue.