Version 2.6 Alpha 6, bridging angle seemingly has no effect

[thwerks]

Description of the bug

Setting "Bridging Angle" setting to any value has no effect. Bridge lines always oriented in same angle no matter the value

Project file & How to reproduce

open any project with bridges, change Bridge Angle value. Only solution appears to be to rotate the part on the the bed to different angle.

rename file to .3mf
Body.txt

After rotating the part:

Checklist of files included above

• Project file
• Screenshot

Version of PrusaSlicer

2.6.0 alpha 6

Operating system

Debian 11

Printer model

Ender 3 Pro

[scottmudge]

This was already reported multiple times. You have to set it in radians, not degrees. It will be fixed.

[neophyl]

Except that according to the notes it was supposed to be fixed in alpha 6.
#9963

[scottmudge]

Hmm yeah something seems off, using your project the bridging angle either comes out at 45 degrees or 90 degrees (parallel to y axis), but it seems to be random every time I slice it. I'm wondering if the bridging infill angle (rather than just dark-blue normal bridges) is determined algorithmically, at 45-degree intervals.

[sarusani]

I'm pretty sure this happens because it's not bridging over "empty space" but bridging over infill. Don't know if it's intended behavior or not.
Bridging over "empty space" behaves correctly and takes the bridging angle into account.

[thwerks]

I'm pretty sure this happens because it's not bridging over "empty space" but bridging over infill. Don't know if it's intended behavior or not. Bridging over "empty space" behaves correctly and takes the bridging angle into account.

Yhe first bridge does attach directly to the infill as expected and does a good job. However the second bridge layer directly attaches to the perimeter and barley touches infill at all, its bridging over thin air and the print fails repeatedly. However, by rotating the part 90 degrees on the bed, the first bridge layer stays the same, but the second or uppermost bridge layer rotates 90 degress and chooses a much more prudent orientation for bridge lines and the print repeatedly succeeds.

Intuitively it seems like the purpose of "Bridge Angle" is so that you dont need to rotate the part on the bed just to correct bridging alignment problems. i.e. the first bridge auto aligned to the infill and works great, but the bridge layer attached to the perimeter seems like it should respect the "Bridge angle" setting as it does not orient to nor anchor to the infill itself.

[kubispe1]

Hello! As you may have noticed, the 'Bridge angle' parameter doesn't control bridges over sparse infill. This parameter only affects the angle of standard bridges. The angle of bridges over sparse infill is determined automatically to follow the infill. We're currently fine-tuning the algorithm to anchor the infill and perimeter in the best way possible.

[thwerks]

really appreciate the reply, hope this can make more sense in the near future. If you can see my explanation the bridging in my case is rather ambiguous and inexplicable. Thank you for your consideration.

[b3n3d1k7]

Hello! As you may have noticed, the 'Bridge angle' parameter doesn't control bridges over sparse infill. This parameter only affects the angle of standard bridges. The angle of bridges over sparse infill is determined automatically to follow the infill. We're currently fine-tuning the algorithm to anchor the infill and perimeter in the best way possible.

I'm trying to print a wide, but narrow part with 0 infill and the bridges to close the part use a 45° angle, which is clearly not the best option here ;-)

As mentioned in the description, rotating the part by 90° fixes the bridges, but the part does not fit onto my printer this way.