Question Cura 5.0.0 - problem with thin structures

[ikorman75 0]

Hi

 

After working for long times with Cura 4, I  decided to try freshly released v5.0 and I have noticed quality degradation on one of my objects. It's actually a small vase which has thin fins, like you can see on images. In 4.13.1 it look fine, while in 5 I can see lot of retractions on the fins which will cause most likely lot of ziting in the final print (did not print it yet from v5). Even print time went from 11 hours to 13 hours,  while retraction time (in percentage) went from 16% to almost 45%. I believe it's connected with variable line with as I can observe that first 1/5th of the fin is drawn as single line and then is converted into two lines, while in 4.x it was build from two lines, in one continues motion.

 

I'm using same 3mf in both versions with same settings - any idea how to overcome this in v5?

 

BR
Ivan

Lamp shade v01.3mf

[winkiethecreator 0]

Same issue. Played with settings for about an hour before I just went back to 4.13 for right now. 

[GregValiant 980]

There are two new settings in the "Walls" section that might be affecting this.  "Split Middle Line Threshold" and "Add Middle Line Threshold".  The default may be around 95% (it's calculated) so try setting them at 50% and see if it makes a difference.

[ikorman75 0]

Thx for the hint, it looks it helps in this case. If set like this, will this model benefit from new variable line width feature or it will be like in 4.13?

 

BR
Ivan

[GregValiant 980]

I'm learning this myself.  I think 5.0 does a better job than 4.13 and earlier on thin structures.  I've been using it on a regular basis (as opposed to the Arachne beta which I didn't care for much).  I used to pay much attention to designing things with wall thicknesses that worked out to an even number of nozzle passes.  Now it doesn't matter as Cura does the math and figures out the width of a middle extrusion.

As you noticed - on thin wall structures a lot depends on how you can convince Cura to travel.  Those vanes in your last image require an out-and-back move.  If you tried to print it with 1 pass or 3 passes the nozzle ends up at the end of a vane and either has to comb back, or more likely, jump to the next vane leaving a string.

I believe you'll like the results.  One thing the Cura Team missed (again) was the "Easy" button.  Ya still gotta think.

[ikorman75 0]

Thx for the feedback, I will play with those settings in order to find optimum setting for certain models.