solid vs bridging infill patterns question
When slicing my current part design I do not understand why prusaslicer is creating extra movement and retractions for the first solid layer over a recess (bridging). This does not make any sense to me, it seems that the slicer should change it's process settings for the bridge sections, without changing direction or stopping/starting. With the way the slicer operates now, with PETG, it causes lots of blobs and stringing issues which lead to downstream issues with print cosmetics and geometry errors.
Here is layer 3:
Layer three makes sense to me, though I would prefer the option to set a SINGLE perimeter wall around text for legibility (the combination of multiple outlines, and the negative space, make the lettering look odd, while setting multiple perimeter walls around other perimeters for strength. Does anyone know how to set that?
Now here is layer 4, where I think Prusa Slicer is flawed in how it is sliced:
Is there a way to force this layer, and the next several solid layers (which repeat this pattern), to be the solid infill only? I think the slicer is might be trying to minimize the bridging lengths with this approach but I don't think it has a big effect. All letters with different angles of bridging look strange. Bridging, direction changes and lifts increase blobbing and stringing which we could reduce by just extending the solid infill to cover the entire interior of the print.
Anyone know if I can set that in PrusaSlicer? Or should I try a different slicer?
The strange pattern continues through layer 7:
Other notes:
* Original Slicer (cannot get Input Shaper to produce decent result, it's unusable with PETG)
* PETG Polymaker, dried, new filament
* MK4 printer
RE: solid vs bridging infill patterns question
Might want to start perusing the PS github. Like this really oldie https://github.com/prusa3d/PrusaSlicer/issues/107 - it explains the reasoning behind what the slicer is doing.
issue 107 though, they are on 13212 now so that should give you some idea how long this has been around.
You might be able to make it slice differently if you used a modifier.
You could use SuperSlicer (although its behind PS and is also rather bug laden at the minute) as that has settings you can adjust to stop it breaking up layers like that.
I will say that recent changes to the solid infill logic does seem to be accentuating this and other related issues more. For example the general logic behind this also causes https://github.com/prusa3d/PrusaSlicer/issues/6275
RE: solid vs bridging infill patterns question
With some searching, I have found the ability to do a single perimeter on the first layer, which solved the multiple perimeters (partially, if this was on a different layer it wouldn't work.
And I found I can set the bridging infill angle to be fixed as well. Even if I set that and the infil angle to be the same, it still results in this:
RE: solid vs bridging infill patterns question
yes. Its defined as different types so as explained in the github issues it slices like that. Just because you make the angle fixed wont make any difference at all.
Your only hope in PS is a modifier and that's a potluck one. Would need an example project to experiment with to see what is practical as like with any slicing how it works is dependent on the geometry on a case by case basis.