dimension problem

[Dobrikk]

Rookie on 3D drawing, but trying to make some bushings in 123D, printed out on a Ultimaker 2+ with 0.4 nozzle from Simplify 3D with 0% infill (should be solid printed) tried with 2-3 shells.

Bushing A and C print with approximately correct outer diameter (7,96mm) but bushing B comes out about a 0.1 over (8,12-8,13mm)
Seeing that I get a Gap fill on B which probably messes up things.

The bushings are print separately. with the same settings.

Thought I was on to something with keeping measures devidable with the nozzle diameter of 0,4mm, but it did not work in Figure B

Any help would be appreciated.

[brian442]

You can use the horizontal size compensation feature to help get perfect dimensions. They talk about it more here:
https://www.simplify3d.com/support/prin ... l-accuracy

[Dobrikk]

I'm happy with A and C dimentions, just can see why B should be any different when the only difference with the modell is the inner diameter.

[dkightley]

I believe this issue here can be seen in the simulation. Cylinder B has the infill showing through the outside perimeter extrusion....which means that there is likely to be far too much plastic being squeezed into too small a space, resulting in the outer diameter being stretched and/or the inner diameter being squeezed tight. In other words, the slicer is not dealing as well as it could with thin walled profiles.

And there are already other issues logged about thin walls..... viewtopic.php?f=23&t=3471

All of these reports of things not printing correctly where there is a thickness of under somewhere around four extrusion widths must all be connected.....at least they are in my humble opinion. If only S3D would actually admit there are shortcomings where thin walls are concerned.

I also think this issue may be related to the issue reported in this thread: viewtopic.php?f=9&t=5860 The perimeter is being pushed out by over-extrusion.

[brian442]

Personally, I don't think this problem is related to the links above. There's no reason you can't use gap fill successfully for a model like this, and if you are really seeing infill sticking through the outlines, that's an entirely different issue altogether.

That being said, I think the green dots you see sticking through are more likely retraction dots or maybe even coasting. It's hard to tell without you posting the actual file.

But I've printed many parts that used gap fill successfully, so I don't have any reason to think you couldn't use it for this too. Check out the original link I posted which has some helpful suggestions about checking extrusion amounts and even using the size compensation if you need to make further adjustments