New unintended behavior in Cura 5.7

[2go 6]

Good morning! I would attach a project file, but these STLs are procedurally generated with millions of triangles and are absolutely huge.

 

Same printing profile and files in 5.5.0 and 5.7.

 

First, 5.5.0 -- how it should look.

 

 

How it looks when using 5.7.

 

1. As indicated by the red circles, these lines are randomly added to perhaps every second or third object on the build plate. Why do they appear? Layer view attached below.

2. (Minor) As indicated by the purple circle, Cura no longer retracts after printing the skirt, resulting in a line being printed.

 

I would appreciate any insight.

 

 

 

[Slashee_the_Cow 268]

If you could provide the gcode files generated by 5.5 and 5.7 we could have a look at that. If they're huge and your problem is at the start of the first layer, from each gcode file just select everything up to ";LAYER:1" (you're probably better off just searching for that, placing the cursor there and holding shift+page up until you get to the top) and copy and paste it into a new file, then go down to the bottom of the gcode file and copy and paste everything after ";End of Gcode" into the file, after the first layer, that should include a lot of your settings.

 

Also you could upload the project files to a service such as Google Drive and give us links to download from there.

 

Also FWIW: .3mf files are already compressed - they're just .zip files with a different extension - but using 7zip (saving as a .7z) at the maximum settings my computer can handle (I'd need more than the 32GB of RAM I already have) I can get about a 65% compression ratio on average for .3mf files.

Alternatively: STL files compress great. There's a file I use for tests (it's a sphere with 4,194,300 faces), uncompressed it's 199MiB. Just using Windows file manager to put it into a zip file brings it down to 72.9MiB. 7z with the highest possible compression? 24MiB. You could put the serious squeeze on the STL file and share that and share a project with the same settings but a very basic model so we can just swap out for the real one.

[Vandrasc 2]

Hi @2go, could you try WeTransfer for sharing a project file? From a quick look we also think that this is caused by travel moves not being retracted, but unfortunately couldn't reproduce on any of my models, so a project file will be very helpful in this case. 

[Slashee_the_Cow 268]

1 minute ago, Vandrasc said:

From a quick look we also think that this is caused by travel moves not being retracted

Ooh! That's a good idea. In the preview in Cura, click the button at the top middle to bring up the line type settings and turn on Travels. Do that for both 5.5 and 5.7 so we can see if they're doing the travels differently.

 

Travels with retractions show up as sort of a lilac colour. Travels without retractions just show up as plain blue.

[2go 6]

Thank you @Vandrasc and @Slashee_the_Cow for your answers. I took a look at Travel settings and sure enough the value for Retraction Minimum Travel changed from 0.8mm in 5.5.0 to 5.0mm in 5.7.

Changed it back to 0.8mm, printed a few of test layers and the issue seems to be completely solved. So most likely just oozing of material during travel moves because of no retraction.

 

Before (5.0mm):

 

 

After (0.8mm):

 

 

Thanks again!