What's all this then?

[Snugg]

I've been a user since S3D came out. From time to time I get quality issues that show up in the preview. No matter what I do, I cannot resolve the issue...and I wind up using something else like Cura. Factory file attached.

The geometry is good. STL exported out of Rhino from clean NURBS objects. I've also ran it through Geomagic looking for mesh defects and there are none.

The holes appear oval, there are gaps in the perimeters (both inside and out) and the quality is subpar.

Anyone have any ideas?

[S3D-Alex]

The holes here appear slightly elliptical because of your current layer height. This is what a circle in profile looks like at .2mm resolution. If you want this to have a more circular shape you will want to use a lower layer height to increase resolution here.

The gaps you are seeing are caused by your current Coasting setting. This is set to 1mm in your profile so your extruder will stop extruding 1mm before the end of every print toolpath. If you are seeing these gaps in your actual print I would suggest reducing this Coasting value.

[dkightley]

Just to clarify what Alex is saying.....what you are seeing IN THE SIMULATION is where S3D is indicating where coasting is taking place in the printing.

If you have coasting set up correctly, you WILL STILL SEE these "gaps" indicated in the simulation. Note that you will not then see similar gaps in the finished print.

The same can be said for retractions. S3D shows a blob whereever there is a retraction. This does not mean there will be a blob in the finished print. Again, S3D is INDICATING where things happen.....not what the end result will be!

[Snugg]

Thank you for the info - that makes sense. I didn't even think that the .2 LH would oval things out - but yeah I get it. What I didn't get was all the other stuff related to coasting.

What do you think a good general rule of thumb should be regarding my retraction settings (coasting et al) - I'm running an Ultimaker 2+ (2.85 with bowden)

[dkightley]

There's not really any rule of thumb. Every printer is different...and you need to tune the settings to YOUR printer!....other than bowden printers need more retraction than non-bowden printers.

Here's a couple of places to start reading up on Coasting and Retraction:
https://www.simplify3d.com/support/prin ... -and-zits/

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