Cura 5.0 - there is "minimum line width", there should be "maximum line width"

[neute 16]

Hi all,

 

the title pretty much sums it up.

I haven't found a way to restrict the maximum line width that Cura chooses. While I love the new variable line width feature, it's become a bit frustrating at times because especially with thin walled prints, Cura chooses one over two lines a bit too often for my taste. Aside from that, there are some more technical materials that I use, which don't like to be extruded at 200 % nozzle diameter and/or the extruder just can't keep up with (looking at you especially, Ultimaker S5 bowden extruder).

 

• It seems as if the variable line width goes up as much as 200 % of the nozzle diameter
• printing a single line wall is a neat feature, but often two wall lines is still preferred, if the wall thickness allows it
• some materials can't be extruded at higher nozzle diameter/LW ratios, especially filled materials (haven't tried with CF though)

 

I could just add a feature request on Github, but it seems as there are a lot of users at the moment that mistake their 3D model's or computer's problems with the slicer's problems, and I don't want this to go under. Also I thought I put this up for discussion and see if other users have the same issue and share my feelings.

 

thanks, best regards

Niklas

[ahoeben 1,948]

Quoting @ghostkeeper from this reddit post:

Quote

You couldn't have both a minimum and a maximum, since they then need to match. For instance, let's say the minimum line width is 0.35mm and the maximum is 0.45mm. If you have a part of 0.7mm it would be 2 lines, but if the part becomes narrower it would be below the minimum line width. But it couldn't combine them into 1 line because that would be above the maximum line width. So you can have only 1 threshold. Cura only has a minimum, so it would combine into 1 line of e.g. 0.699mm width.

 

[ghostkeeper 105]

Quote

printing a single line wall is a neat feature, but often two wall lines is still preferred, if the wall thickness allows it

So then reducing the Minimum Wall Line Width will allow it to print with two walls then, using thinner lines. Does that not solve your problem?

 

Effectively, you could see the Minimum Wall Line Width simply as the threshold at which it starts using more, thinner lines.

[GregValiant 1,251]

There it is from two of the guys that really know.

There are two new settings that have an effect on this.  They are in the Walls section "Split Middle Line Threshold" and "Add Middle Line Threshold".  I have not played with them much, but they tend to limit the extrusion width allowing for a higher counts in narrow places.  They are percentages rather than some hard coded absolute.

To paraphrase from the popup help balloon - Increase the number to use fewer and wider lines and decrease to use more and thinner lines.  So it would appear that there is some adjustability in the max line width.

Edited June 2, 2022 by GregValiant

[neute 16]

thank you guys, I hadn't thought this far but it makes a lot of sense.

I will try to adjust the minimum line width setting. 

...I do think that the new engine brings a lot more flexibility but we'll have to get used to it and learn all the parameters to become arachne masters!

 

Best, Niklas

[ahoeben 1,948]

On 6/2/2022 at 4:44 PM, GregValiant said:

There it is from two of the guys that really know.

Well, I just quoted the other guy...

[GregValiant 1,251]

Alright, I'll buy that.  I'm not going to retract my statement though.

Besides, isn't he the guy that hated single layer prints so much he wouldn't let them slice?