Unnecessary Travels During Skirt

[joegatling 0]

Cura has recently started generating skirts that print on an odd sequence and contain a lot of unnecessary travel moves. Below is an example printing a simple cylinder.

 

 

As you can see, the skirt prints in a strange sequence rather than printing each loop sequentially. It also travels to seemingly random places for each loop. The gcode is attached as well.

This is sliced using the default normal profile using Cura 5.1.1 with nothing changed other than changing the plate adhesion setting from brim to skirt.

 

What is going on here? Is this a Cura bug?

 

SkirtTravel.gcode Part Studio 3 - Part 1-2.stl

Edited October 1, 2022 by joegatling
Fixed the formatting. Added Cura version

[joegatling 0]

UPDATE - I just downloaded the 5.2.0 beta and the same model slices properly now. I can't see this particular issue called out in the build notes, but there is a mention of brims printing in the wrong order. Perhaps it is related to that.

[joegatling 0]

Actually, I don't know if this is related. I am trying to use a concentric bottom layer, and it is also doing some unexpected travels during the bottom layer:

 

[GregValiant 1,410]

I've noticed that odd behavior myself.

There were several bug reports made on Github (regarding Cura 5.1) and the Concentric patterns when used as skins, infill, ironing, and support.  This "not putting the layer down ring by ring" was one of them.  When there are travel moves on a top skin there can be scars from the travels.  On the bottom, not so much - unless there is some oozing during the travels.

[MariMakes 206]

Hey @joegatling,

 

Welcome to the Ultimaker Community 🚀

This seems to be related to a bug in ordering the concentric initial layers.
If you select a different initial layer pattern it should work better. We are aware of the issue, it's also reported here https://github.com/Ultimaker/Cura/issues/12977
 

We have a ticket to the backlog with the intent to improve this. 
I'll add your model as a testcase for our testers. 

Thanks for the report! 👍 

[JabroNole 0]

I've also noticed this issue with skirts on 5.1.0  The single skirt line would move back on itself lifting from the build plate and cause issues with my prints.  Glad to hear that it is on the fix list for future development.  I never had this issue in 4.13.  Thanks!

[GregValiant 1,410]

I haven't seen the problem in 5.2.1 at all.  Nice job by the Cura team.

 

I'd buy them a round of "Likes" but there is only the one button.