Print outline around surface layers to improve surface edges

[wolfpackmars2]

Top surfaces of a print which contain layers above print very poorly. This is because it appears that Simplify3D does not include outlines for the surface layers to adhere to below the top layer. I don't really know how to explain, but hopefully some images will help.

I've gotten around this by setting up multiple print processes, and printing a few layers with solid infill before the surface layers begin to print. However, this is very time consuming for prints with many surfaces at different heights of the model.

Cura seems to avoid this issue by printing an outline of walls with the solid layer. Another solution, though somewhat less elegant and more wasteful, would be to print surface layers as a complete solid layer.

I've indicated the problem areas in the attachments.

*Edit: changed the title to better clarify the issue

[horst.w]

The FACTORY file would help to help!


Regards
horst.w
GER

[wolfpackmars2]

No problem. I've attached the factory file I'm currently using.

It has several process groups for a few different prints I'm working on at the moment. The process2 group is the most complex, where large object is being printed with several different floors and a few critical stress points in the model which need to be strengthened. I'm laying down one solid layer before any bottom surface is printed, so that the bottom surface has a solid foundation to sit on.

[wolfpackmars2]

To expand on my initial post, it seems the problem is exacerbated by the fact that the floors are projected beneath the surface. I've included a few more screenshots to demonstrate. The yellow "floor" is infill.

I also included a screenshot from Cura. You can see that Cura includes a solid outline before laying down the surface to give the edges of the surface something to adhere to.

If this can be fixed with settings in the current version of Simplify3D, that would be great. This problem goes beyond just appearance. It can create blobs and bumps if the surface plastic warps upward during print, which can snag on the printhead and cause bad things to happen.

[wolfpackmars2]

Here are some screenshots from Cura. You can see it prints an outline around the bottom surface layer to give the edges of the surface layer something to adhere to around the perimeter. It's a single extrusion, but it makes a world of difference when printing bottom surfaces. The outline is printed as part of the outline process with the walls, and is laid down before the floor surface.

The sparseness of infill does have an impact on how pronounced the problem is, but the problem is still present unless using a solid infill beneath any bottom surfaces.

[horst.w]

Don't compare Cura with Simplify thats are different things!

You have created a lot of processes I cannot see what the reason is. Prepareing to print produce overlaping how ever and shows the issue.
Only choosing the first process the print is ok.

H.

[dkightley]

Before I discuss the issue of this thread......you have far, far too many processes stored in the workspace. One day, you will lose the lot of them and you'll be distraught. Read this post of mine where I explain how to use processes : https://forum.simplify3d.com/viewtopic. ... ess#p32468 By using and storing processes and profiles correctly, you'll not suffer the pain of losing your valuable settings!!!!

Now onto the subject of the thread....
What you are describing has been reported on this forum several times over the past few years. Its a deficiency in the software that Simplify3D seem to refuse exists...and I believe their last response was something like....Add a new process to increase the infill just below where the surface prints. This , obviously, is no way a suitable solution, but is in fact a bodge of a work-around to get them out of addressing the real issue.....the deficiency in the slicer logic.

So....in the short term, the best that can be done is to insert a process change say 10-20 layers below the stepped surface and increase the amount of infill....and perhaps change to a different infill type such as Full Honeycomb. This will increase the amount of support under the unsupported change of filament direction. perhaps changing the external fill pattern to Concentric may also help.

In the long term.....Simplify3D need to recognise that there is a deficiency in the software that has spoied hundreds of prints over many years....and making users compare the performance of the software with other slicers in a negative way......and even cause them to move away to other software!

[arhi]

note that "quick workaround" is to have more shells.
the "edge" of the flat surface printed as top will come out to second perimeter from inside so if you have 2 perimeters your outermost perimeter on the upper part will go on top of the edge of the top infill of the bottom part and that will be awful quality edge. now if you have 3 perimeters the middle perimeter will go over the edge of the top of the bottom part so you will have one perimeter (the outermost one) going perimeter width over the top giving you acceptable edge. with 4 or more perimeters all perimeters after second inside one go over the top fill giving you great bond and ideal finish... 4 perimeters for this type of parts, if you are using springy plastic and thin extrusion width are imo minimal for s3d, ofter 5 is required (for abs and pla i use 4, for petg i use 5, for pp, hdpe i use 6 )

[horst.w]

@ Doug Kightley

Doug, you are right for all,

but things are existing and with reasonable settings this object is to be print in a very strong way without any deficiency. With only one process, varieties are possible ...
The transition between the first top layer and the infill of the growing up tower is only the INSIDE of the tower, this brink will not be seen - why crying about, don't worry!

No discussion about nearly 20 processes, but all other settings are also more than poor.

After printing the 5 top layers, where the infill of the tower is also growing up without any interruption to the base area and is building a unity together, S3D is printing the towers perimeter on it.
For this case I can't see any deficiency ether strong printing or optical issues. May be, that very special objects have disadvantages with this strategy, but mostly it is more than sufficient.

With 5% infill and other poor settings, we say in Germany, you can'nt win a flower pot. I don't know what Cura is setting automatically, but surely it is not comparable with 5%.

Regards
H.

The pictures are showing my normal settings, here the beginning of top layers and 2nd the first layer with perimeters of the tower

[wolfpackmars2]

This: https://forum.simplify3d.com/viewtopic.php?f=23&t=7906

As for all the processes... there are a couple of groups of processes customized for the part they are printing. Not all parts for all processes are present in the example I posted. I should have removed the extraneous processes to reduce confusion.

But, the ultimate answer is that this is a problem inherent in the design of the software, and S3D doesn't seem keen to fix it. The solution is to increase infill, but I'm not the only one to claim BS on that.

Dkightley, your solution of adding processes to add a solid infill before the problem layer is what I have been doing. The result is "way, way too many processes" and it's very time consuming and not to mention wasteful to have to print solid infill layers. Increasing infill makes the problem appear smaller, but what you will end up with is many smaller defects instead of a few large defects.

Bummer, aside from this, S3D has been perfect for me so far. I can't say this is acceptable, but S3D already has my money so they have little reason to care what I think at this point.

More related posts on this subject:

https://forum.simplify3d.com/viewtopic.php?t=1809