How do I get a clean top layer?

[FraggleRock 5]

Does anyone know why am I getting this really messy top layer and how can fix it?

It is smooth to the touch but it reflects light in a very unpleasing way. I wish the pattern was uniform all the way. I'm using a UM3

[AndersK 59]

Hi, you can get a lot better result if you enable Ironing (at the end of Shell tab)

 

Depending on material you can get good results with 4-10% Ironing flow, begin with 5% and see how it works.

 

 

 

 

 

 

[DarRAven 4]

Also enable z hop in travel settings that will prevent that travel movements

Note: It will cost more printing time

Edited May 5, 2020 by DarRAven
typo

[FraggleRock 5]

6 hours ago, AndersK said:

Hi, you can get a lot better result if you enable Ironing (at the end of Shell tab)

 

Depending on material you can get good results with 4-10% Ironing flow, begin with 5% and see how it works.

 

 

 

 

 

 

I tried some ironing yesterday with the default settings (although i changed the pattern to concentric)on a smaller test model, and it created some unwanted bumps in the middle of each pattern. It was definitely flatter and more glass like but it still looked like what you get from a milled metal surface. What I would like to understand is why the regular zig zag fill reflects the light differently when the head moves to a different location? Is the head positioned slightly higher or lower on the z, so  the material is thicker enough to reflect the light differently? I don't get it. I wish cura had the option to treat  the whole layer as one pass and build on it after it's done with a uniform zig zag fill. Anyway, I'll try the ironing with the zig zag pattern today to see if it is any better.

[FraggleRock 5]

2 hours ago, DarRAven said:

Also enable z hop in travel settings that will prevent that travel movements

Note: It will cost more printing time

Thanks for the tip. I'm surprised z-hop is not enabled by default. These travel traces are not something anyone wants to look at on a finished print.

[geert_2 558]

Silver and pearl filaments contain particles that reflect light in different directions. It is the orientation of these particles that causes very visible lines. If you use a solid color that is not too high gloss, thus rather satin, and a little bit translucent (but only very slightly), the lines will be less visible.

 

Another option would be to learn to live with this, consider it a normal aspect of 3D-printing. Like sand is rough, metal is shiny, etc... It's the way it is.

 

Edited May 5, 2020 by geert_2

[FraggleRock 5]

3 hours ago, geert_2 said:

Silver and pearl filaments contain particles that reflect light in different directions. It is the orientation of these particles that causes very visible lines. If you use a solid color that is not too high gloss, thus rather satin, and a little bit translucent (but only very slightly), the lines will be less visible.

 

Another option would be to learn to live with this, consider it a normal aspect of 3D-printing. Like sand is rough, metal is shiny, etc... It's the way it is.

 

I understand what you are saying. Yet I feel this could easily be fixed by opting to close each top layer like a shell instead of  laying material around the holes which is a process that breaks the top layer path into several different looking patches. I wonder if any of the thousand options in cura can do that already.

[FraggleRock 5]

I think I found a solution to the problem. I'm reprinting the whole model for visual comparison and I will post later with the result if satisfactory.

[FraggleRock 5]

Here is the new print. It does have some artifacts which are partly because I got too frugal with the number of top layers this time, to speed up the print, and it revealed some creases from the infil pattern under, as well as some other issues that wouldn't show up if only it got more layer passes. But the fundamental issue of the different patches is gone! I think I will combine it with some ironing and it will look like smooth metal for sure!

[SandervG 1,521]

Looks good! 🙂So which settings eventually made the difference for you?

[DarRAven 4]

10 hours ago, FraggleRock said:

Here is the new print. It does have some artifacts which are partly because I got too frugal with the number of top layers this time, to speed up the print, and it revealed some creases from the infil pattern under, as well as some other issues that wouldn't show up if only it got more layer passes. But the fundamental issue of the different patches is gone! I think I will combine it with some ironing and it will look like smooth metal for sure!

I am glad to be able to help you 🙂

[FraggleRock 5]

4 hours ago, SandervG said:

Looks good! 🙂So which settings eventually made the difference for you?

Apart from the suggested z-hop, I also enabled "Retract at layer change" and I don't know which of these or both helped but those layer change lines disappeared.

The big  difference that fixed the patchwork didn't happen from settings though. I separated the letters from the top layer (in the model) by .02mm enough so that the slicer doesn't create a hole at their base. That way the top surface prints as one uninterrupted flat area, then adds the letters on top starting on the next layer. The 0.02mm gap worked with 0.1mm layer height setting. Any other layer height might need a different/larger gap to avoid making a hole during slicing. So people who try this at different printing resolution should check the layers in the preview first to make sure the top surface closes before anything on top of it starts.

It's an easy fix, but if this eventually became a cura feature that would be awesome!

[SandervG 1,521]

26 minutes ago, FraggleRock said:

I separated the letters from the top layer (in the model) by .02mm enough so that the slicer doesn't create a hole at their base. That way the top surface prints as one uninterrupted flat area, then adds the letters on top starting on the next layer.

That is smart! 

[FraggleRock 5]

Thanks! I'm just glad it worked out and maybe other people will find it useful.

[SandervG 1,521]

1 hour ago, FraggleRock said:

Thanks! I'm just glad it worked out and maybe other people will find it useful.

That is exactly what this community is about! 👍

[DarRAven 4]

2 hours ago, FraggleRock said:

Apart from the suggested z-hop, I also enabled "Retract at layer change" and I don't know which of these or both helped but those layer change lines disappeared.

The big  difference that fixed the patchwork didn't happen from settings though. I separated the letters from the top layer (in the model) by .02mm enough so that the slicer doesn't create a hole at their base. That way the top surface prints as one uninterrupted flat area, then adds the letters on top starting on the next layer. The 0.02mm gap worked with 0.1mm layer height setting. Any other layer height might need a different/larger gap to avoid making a hole during slicing. So people who try this at different printing resolution should check the layers in the preview first to make sure the top surface closes before anything on top of it starts.

It's an easy fix, but if this eventually became a cura feature that would be awesome!

I think you should suggest it right here: https://github.com/Ultimaker/Cura/issues

[FraggleRock 5]

7 minutes ago, DarRAven said:

I think you should suggest it right here: https://github.com/Ultimaker/Cura/issues

Thanks. I will do so.

 

[geert_2 558]

On 5/6/2020 at 3:09 PM, FraggleRock said:

Apart from the suggested z-hop, I also enabled "Retract at layer change" and I don't know which of these or both helped but those layer change lines disappeared.

The big  difference that fixed the patchwork didn't happen from settings though. I separated the letters from the top layer (in the model) by .02mm enough so that the slicer doesn't create a hole at their base. That way the top surface prints as one uninterrupted flat area, then adds the letters on top starting on the next layer. The 0.02mm gap worked with 0.1mm layer height setting. Any other layer height might need a different/larger gap to avoid making a hole during slicing. So people who try this at different printing resolution should check the layers in the preview first to make sure the top surface closes before anything on top of it starts.

It's an easy fix, but if this eventually became a cura feature that would be awesome!

 

Exellent idea. The difference is quality is huge.

 

This is a trick to remember.

 

[jlaw904 0]

In addition to what's already been said, I've found that adjusting my top layer flow rate independently of the others has helped a lot. I adjusted my flow rate to get perfect layer lines and found it was underextruding the top layer ever so slightly and bumped the top layer flow rate up by 3% to get great results.

[DarRAven 4]

On 5/6/2020 at 4:09 PM, FraggleRock said:

Apart from the suggested z-hop, I also enabled "Retract at layer change" and I don't know which of these or both helped but those layer change lines disappeared.

The big  difference that fixed the patchwork didn't happen from settings though. I separated the letters from the top layer (in the model) by .02mm enough so that the slicer doesn't create a hole at their base. That way the top surface prints as one uninterrupted flat area, then adds the letters on top starting on the next layer. The 0.02mm gap worked with 0.1mm layer height setting. Any other layer height might need a different/larger gap to avoid making a hole during slicing. So people who try this at different printing resolution should check the layers in the preview first to make sure the top surface closes before anything on top of it starts.

It's an easy fix, but if this eventually became a cura feature that would be awesome!

I recently made a test about this and find out it decreases the durability around %5-10

Edited May 11, 2020 by DarRAven
note it can change on your filament

[FraggleRock 5]

Just wanted to add for everyone to know, that I submitted this feature suggestion to Github and the members there deemed that there is a Cura setting that can close holes called "Top Skin Expand Distance" (not a setting I could find until I was told about it) for which if you increase the value, it eats away the walls around holes until they are completely closed. So it won't make it to a feature list, but at least keep in mind that there is this setting that can make a full and even top layer for you.

Edited May 11, 2020 by FraggleRock

[FraggleRock 5]

1 hour ago, DarRAven said:

I recently made a test about this and find out it decreases the durability around %5-10

Interesting... Try increasing the "top skin expand distance" value instead to see if it fuses the two layers better instead of an artificial gap.

 

[Nimneu 0]

This is a slightly different solution to the issue and may not be suitable depending on the desired effect. However. Interpreting the question as “how do I hide the lines on the top surface” rather than “how do I make the too perfectly smooth” another option is to enable the fuzzy skin option, which instead of smoothing the too layer will add a controllable amount of texture to the surface. I’ve not tried this myself yet but I have seen some really lovely prints using this feature and the prints have a really manufactured feel to them. It does however depend on the effects t you are after.