Poor Print Quality of 'Fins' on Geometry

[jamespoche 0]

Hello,

 

I am working with the Ultimaker s5 and have been consistently receiving poor fidelity when it comes to the 'fins' details that populate the surface of my geometry. Their dimension well exceeds the smallest part (printing with a .4mm nozzle and they are roughly .6mm). 

 

 

I have tried slowing down the print (from 70m/s as default to 45m/s), heating up the material (from 200 as default to 210), scaling it up incrementally (I am at bed capacity now with the current iteration), and even different mesh generation strategies resulting in all the same issue.

 

 

What is interesting is that it errors differently at different locations on the print, for instance, here is another side of the same, aforementioned print:

 

 

This is almost acceptable. It is also closer to the origin, could this be a clue? To add, these printers have been going non-stop for nearly 6 months with a few maintenance checks in between.

 

I welcome any thoughts, ideas, and questions.

 

Thank you in advance!

[GregValiant 1,115]

I call it the "Comb" problem as in hair comb.

First, try adjusting your "Minimum Line Width" down.  If those fins are 0.58 wide then a Minimum Line Width of 0.29 or 0.28 should fit twice.  That will force Cura to do an Out-and-Back extrusion on each fin.

 

If Cura decides that a single extrusion will be sufficient, then that's what you will get...an extrusion out to the end, travel to the next fin, an extrusion back to the base of the fin.  That travel across the ends of the fins often leaves a string connecting the ends of the fins.  It doesn't do it every time, and it varies from layer to layer.  

If you turn on the "Starts" in the layer preview I think you will see that there are a lot on the fin ends.  Ideally you don't want any.  Whether it's possible or not you'll have to experiment.

These are .58 wide and the minimum line width is the default .34 for a .4 nozzle.  The white marks are the extrusion starts.  I think the problem here is obvious.

 

This is at .28 Minimum Line Width.  There is one fin that has the normal Z seam on it.  The rest are "out and back" extrusions and the nozzle doesn't stop.

Edited June 1 by GregValiant

[jamespoche 0]

Exactly it! Thank you.

[GregValiant 1,115]

This is further proof that even a blind squirrel finds a nut every once in a while.

 

Cura 5.x is different than previous versions.  There are new settings (particularly in Walls) that we have to get used to.