Support guidance needed....

Can anyone offer any tips?

Is there a quality setting for the first part layer that prints after the support?
Example: cylindrical part w/ a flange on top. Support prints all the way up to flange.
The first layer(s)/surface created on top of support looks horrible.

FYI - I have been using the medium or fine slic3r config downloaded from the site.

  • I have played with support pattern and spacing with no luck there
  • (I don’t have a part to show right now, because I’ve trashed everything that comes out that way)


Can you post the .stl and gcode?

I cannot post the files, the part is proprietary to my company.

Increasing the density of the support material will help reduce sagging of the first layer on top of supports.

Are you using Slic3r? If so, have you tried v1.0? I noticed, this weekend, the support generation has been improved with the 1.0 release.

Slic3r 1.0 seems to do a better job of reducing the gap between spacing at the top of the support, just before the first part layer is deposited.

I used 1.0 at the default support settings for this part. It is not the best picture in the world but, the part surface that was in contact with the supports looked nearly as good as the top surface.

  • Slic3r 1.0 is what I’m using.
  • I have used various numbers for pattern spacing
    I tend to use 4 since it makes it easier to remove support. I have used lower, including the default, but don’t see
    much difference in quality. The rest of the part looks good. Just the first layer after support is the issue.
  • When you say “I used 1.0 at the default support settings”, which settings are those?
    So when you remove the support, it looks as good as the rest of the part?

I think 2.5 mm is the default spacing. I am talking about the support settings you get when you load up Lulzbot’s slic3r profiles. I have been using the medium quality with support profile and just turning off supports when I don’t need them.

It doesn’t look as good as the rest of the part. I don’t think that is possible since it is laying filament across the gaps in the support.

You could always try a different slicer. I have been testing with Cura lately. It is not as configurable as Slic3r but it does seem to turn out really nice parts. Especially the side walls and holes. I did have to increase the support to part gap in x and y so the supports didn’t stick to the part as much…

Some Cura examples and my ini file here:

Here are a couple pictures of the support and non-support side of the part.

I printed again, making sure to use the same settings as you mentioned.
I actually used the fine auto support config (Pattern spacing 2.5).

Here is what I am getting.
This picture is of the first layer AFTER the support (the issue).
The end you see was the end on the bed.

Maybe print an insert disk bed side down to glue into that recess to improve surface quality? You would need to build in clearance for it but end product would be much better. Remember to bevel the edges of the disk ft or best fit.

What does that layer look like when you scroll through the gcode?

Pardon my ignorance :smiley:
I can open the gcode, view the settings, but I honestly have no idea how to find an exact layer in the gcode.

You will be viewing a 2d or 3d representation of the extrusion produced by the printer, for each layer, based on the gcode. Not just viewing the gcode text itself. It might let you see why that layer is so ugly. It looks like the supports are too far away from the first layer of the part. I don’t recall seeing anything in Slic3r to adjust support offsets, but, in Cura you can manipulate how far away from the part in x, y and z the supports are built. It is a pretty handy feature.

You can do it online, here:

Repetier Host has a nice viewer and so does Cura. I didn’t use Pronterface much so, I don’t remember how it handles gcode viewing.

Thanks for the link!
I loaded my gcode and found the layer in question, but not really sure what I’m looking for.

I was thinking there might be a bug in the slicing where the supports are ending too far away from the first layer of the part. You might be able to identify that in the 3d gcode view if there was an obvious gap between the supports and part.

Is the surface we are looking at in your picture the supported surface or are the supports on the inside of the object, holding up the surface we are looking at?

Edit: I just looked at the picture again and I see that this was the supported surface. When you removed the supports, were they firmly attached or did they just pop right off? Were they attached to the supported surface or were they just attached to the circumference of the part? It just looks like that first layer was not supported well and was basically bridging the gap.

In slic3r you should be able to adjust the interface layer and spacing, but I prefer to draw support structures into the model a lot of times.

A good description of support options in slic3r is available at

I do not notice any obvious gaps between the support and part. The support comes out good for the most part (especially since I have the interface layer set to 0).
Yes, the surface in the picture is the supported surface.

As I mentioned above, I have been using the interface layer at 0. This does not help that surface quality.

Since I cannot share the actual .stl and .gcode files due to proprietary reasons, I created and printed a fake part to show the issue. I have attached 4 files into a zip file of a sample part with support

  1. orientation.jpg - shows how I printed the piece
  2. supprt_issue.jpg - shows the surface with the issue
  3. test.stl
  4. test1.gcode
  • I cannot just flip it over and print w/o support. Since this is only a representation of the actual part, you can’t see that I would need support the other way, as well.

FYI - I sent this information to Lulzbot for some help, but have gotten little help.
The best I’ve gotten back is to use dual extruders and print disolvable material for support.
I know this is an option, but I’m not set up for that yet. (1.35 MB)

I looked through your posts but saw no mention of the interface spacing, oh well.
Have you considered printing the object as multiple parts and joining them together after printing?

When I said “mentioned above”, that was in the same post, not previous posts. Sorry for confusion.
I can print this as multiple parts and glue together, but I shouldn’t have to.

Ah, my misunderstanding then.
I hope you figure something out that works for you, but I doubt you will attain any results that are as good as from printing in multiple parts.
Slic3r 1.1.0 is still an experimental release, but there are some new things related to support in it that may help though.