4.6.1/4.8.0 Bridge Skin/Sparse Infill doesn't activate Bridging if Infill is 0%

[sg000]

Application version
4.6.1 and 4.8.0

Platform
Windows 10 64 Bit

Printer
Custom

Reproduction steps
Take any model. Activate Bridging.
Set infill to 0% and the Bridge Sparse Infill Max Density to Anything greater than 1
Slice
*notice no bridging.
Go back and set infill to 1% (making sure the sparse infill is still greater than 1
Slice
*notice we now have bridging, but also 1% of infill (which I did not desire)

I tried changing other settings like Support Threshold, Wall length but until infill is not 0%, bridge skin just doesn't activate.
This is not helpful when trying to create an empty cavity without any infill

[Ghostkeeper]

Indeed, I could reproduce this issue. You removed the "Project file" entry from the template so it's always a gamble, but I could find your case: infill_density_0_not_bridging.zip

0% density is a bit of a special case in CuraEngine since it skips the entire infill generation then. That's probably what's causing this issue.

[sg000]

Indeed, I could reproduce this issue. You removed the "Project file" entry from the template so it's always a gamble, but I could find your case: infill_density_0_not_bridging.zip

0% density is a bit of a special case in CuraEngine since it skips the entire infill generation then. That's probably what's causing this issue.

I'll remember not to delete that.

Also, found a workaround in a way. It does accept non-integer for the infill %, so setting to 0.1% provides desired outcome for my model anyways.

[Ghostkeeper]

We'll recognise this issue as a real problem, but it doesn't get any priority from us now. We'll defer it.

The main reason for this decision is that it's a bit of an edge case. While there's good reasons for the user to look specifically to this edge case (when printing with 0% infill, bridging is more important), it's a pretty rare combination of settings and involves the experimental bridging feature as well.

When we're going to push to bring those bridging settings to a more stable state, we'll probably take a look at this again. But not for now, unless a fix is contributed to us externally.

[hoffor]

this happens when setting top/bottom layers to 99 (effectively 'disabling' infill(?)). this is what i do when i want 100 percent infill, i just use all skin because i typically use an extra infill wall for lower density infills, but i don't want it when doing 100% infill because it messes with the patterns, so i just increase skin since the infill line would just be another setting to toggle and keep track of

[github-actions]

Hi 👋,
We are cleaning our list of issues to improve our focus.
This bug seems to be older than a year, which is at least three major Cura releases ago.
It also received the label Deferred indicating that we did not have time to work on it back then and haven't found time to work on it since.

If this is still a problem for you in the current version of Cura, can you please leave a comment?
We will have a fresh set of eyes to look at it.

If it is not a problem anymore, you don't have to do anything, and this issue will be automatically closed in 14 days.

[sg000]

Hi 👋, We are cleaning our list of issues to improve our focus. This bug seems to be older than a year, which is at least three major Cura releases ago. It also received the label Deferred indicating that we did not have time to work on it back then and haven't found time to work on it since.

If this is still a problem for you in the current version of Cura, can you please leave a comment? We will have a fresh set of eyes to look at it.

If it is not a problem anymore, you don't have to do anything, and this issue will be automatically closed in 14 days.

As far as I know this still isn't fixed. I've continued to use 0.1% infill on all new releases, but I've not specifically tested otherwise. I recognize its an edge case (user wants no infill, but does want bridging). Workaround is still to use 0.1%, but new users won't figure this out easily.

[MariMakes]

Hey @sg000,

I'm a fresh set of eyes, reporting for duty 🖖
Sorry, it took us a while to get back to you 😞

I can confirm that this issue is still present in Cura 5.4. I also recognize that the workaround isn't ideal because it results in infill being printed where you don't want it 🤔

I'll bring it up to the team to see what they can do to improve it.
But I expect that if it's not a quick fix that it will not get a high priority to implement.
Fingers crossed 🤞

[MariMakes]

Quick update from our side 👋

We've added a ticket to the backlog with the intent to improve this.
For internal reference CURA-10823.

Thanks for the report! 👍

[MariMakes]

This is resolved in the 5.5 Beta release 🎉 , you can download the Cura version with the fix here: https://github.com/Ultimaker/Cura/releases/tag/5.5.0-beta.1
I'll close this issue since it's resolved.

Thanks again, and please let us know if you run into any other issues 💪