Superficial finishes Cura 3.3.1 Ultimaker 2+

[nachete 0]

Hello everyone,

 

This is my first english post in this forum and I hope it is not the last one, I really want to learn and at the same time share my experiences with all of you.

 

Well I have an Ultimaker 2+ printer one month ago and it is the first one with "open" software to be able to configure the different printing parameters.

 

I am progressing little by little but now I am blocked with superficial finishes and I would appreciate it if you please help me.

 

A picture of piece (PLA of the brand Fillamentum).

 

I do not know if it's the problem of the retraction or the temperature or both but it seems the nozzle extrude more material than it should.

I tell you adjustments:

 

Layer 0.15
Speed 30-40mm/seg.
Temperature 205
Retraction 6.5 mm
Speed retraction 25mm/seg.

 

Let's see if you can please give me some guidance, if you need more information, tell me.

 

Thank you very much!!

[SandervG 1,521]

Hi @nachete, thank you for your post and welcome to our community! 

If I understand it correctly, you want to learn how to improve the surface of your print, correct?

Is it only top surface or also the walls (sides) of your 3D print?

 

From the first look, I would say your print doesn't look too bad at all so you're already doing a good job by the looks of it! 

 

If you're after improving the top surface, do you want the lines to disappear? Have you ever tried the setting 'ironing'? It is listed under 'shell', and generally it should give smoother top surfaces. 

 

Good luck!

[nachete 0]

Thank you SandervG,

 

The walls and infill are perfect.
The problem is the superficial finish, the lines is not a problem for me, i like it ?.

 

I have got to improve the finish changing the surface finish, lines to zigzag, to reduce the retractions.

I have also changed the retraction to 5mm and the speed to 30mm/sec and the temperature has dropped to 200°.

 

The surface finish has improved, then I put a photo, but the marks of the nozzle in the zones where it makes small fillings still appear.

 

I do not know if the solution is to increase the speed of retraction or lower the temperature more or increase the speed or acceleration of the Z axis... if someone please can guide me a bit to get some finishes similar to these that I got with another printer.

 

Thank you!!
 .

[nachete 0]

This morning I have been trying to adjust and it has improved a lot, almost perfect but It still leave the circular mark of the nozzle when it jumps from one zigzag to another. Someone who has happened something like this and has solved it?

 

Settings:

Temperature 200/198/195
Layer 0.15
Speed 35mms
Retraction 5mm / 35mms
Retraction minimun travel 0.8mm
Maximum Retraction Count 90
Minimum extrusion distance window: 5mm
Top/Bottom Pattern: Zig Zag
Coming mode: No Skin
ZHop:  activate / 0.2mm

 

Photos of the three temperature variables, there are no significant changes and with the first printer.

[gr5 2,235]

If you are doing test prints expect to do 50 and so try printing much thinner parts and smaller parts.  Maybe print *only* the "aul"?

 

Try turning off combing.  And try "ironing" as Sander said.

 

Or at least turn combing off for the top layer (I think maybe that's an option?).

 

Combing is a feature where, when doing infill (don't think top layer - think internal layer) if it needs to move say from one side of a "U" to the other, it takes the long path so that you don't get a string across the top of the U.  That's combing - it follows an inter path.  But the other thing about combing is that it disables retractions.  So if you disable combing it will retract.  Then you should also *maybe* consider the "z hop when retracted" feature.  Normally that makes the quality worse but for your top layer it might help.  I'm not sure.

 

But really the IRONING feature should help you the most!  it was invented by someone who makes lots of key chains.  Similar to your prints!

 

[gr5 2,235]

Also in your second photo - the blue one - you have quite a bit of underextrusion.  You may have printed it too cold, or too fast, or maybe you need to replace your TFM teflon part.

[nachete 0]

Thanks Gr5. 

 

Yes, I am doing tests and I do not lie to you, I have more than 25 "aul" made. 

 

I have set the "Combing" only for the skin and the "Z hop" to 0.2mm, but it only acts in the retractions of the layer change. 

 

The last thing that I changed this afternoon is the retraction to 4.5 mm and the speed of retraction I have raised it to the maximum 45mm/s. 

 

I have disconnected the option to fill gaps between lines.

 

The results you can see in this photo, the "aul" below is the improved version.

 

Then I tried changing the Top/Bottom pattern from Zig-Zag to lines and I think we have improved another bit.

In the photo the initial keychain, under the test in Zig-Zag and below the test in lines

 

The last the Ironing test that it has not been very homogeneous.

Tomorrow I will try to test these same settings with other temperatures but I would appreciate it if someone has some other solution to reduce the nozzle marks.

 

The blue key chain is not made with the Ultimaker, it is made with a closed software printer but I like its homogeneous finish.

[fergazz 60]

you can find more info about ironing seaching for: neosanding

 

4.5mm retraction looks ok for PLA (standart value), 45mm/s z speed looks to fast for me... I'm always beetwin 25mm/s and 35mm/s in my UM2 with the black feeder.

 

I'm using Simplify3D for a while so I cannot help to much on Cura settings but turning off combing should do the job... in Simplify3D there are some tricks to avoid layer marks on top layers at advanced tab. 

 

 

[SandervG 1,521]

How thick is your top surface? You should have approx 3 top layers.

I don't think you should need to alter retraction length. Maybe you have made too many changes to your profile. Could you try a default profile with ironing turned on?

[nachete 0]

Thanks Fergazz, following your advice I have lowered the retraction speed to 35mms and the finish is the same.

Thanks SandervG, the surface thickness that I use is 4 layers. 
I have made a test print with the default profile for the Ultimaker 2+, 0.4 nozzle, layer 0.15 and PLA (I have only changed the temperature to 200).
I put a photo, up default profile, down best print with my settings.

Then I have tested with the different surface finishes.

The ironing finish is still not homogenous, maybe the speed of 20mms is too slow and it heats the surface too much.

 

As you can see the problem are the nozzle marks that it leaves when it has just filled one part of the surface and it goes on to fill another part. 
Here the option of "Zhop" would be perfect but in these changes of fillings it is not activated.
The only solution is to accelerate these final fillings and for that I think only increase the speed of retraction and the speed of the upper layer.

The piece below is the result.

If someone has a better option, please share it, thank you!!

[nachete 0]

After too many tests ...

 

Finally I got the finish I wanted (below piece)

 

I have modified the width of the wall and the number of walls to only one and practically nozzle marks have disappeared.

Surely I can refine a little more.

Thank to all.