3D printing is booming–big time. And since most 3D printers accept STL exports, engineers are using the export format more and more.
I’ve experimented with 3D printing using different settings of the STL export format. In this article, I’ll share my experiences with you. For the sake of accuracy, for these tests I used NX 11 and an Ultimaker 3D printer.
My first experience with round 3D parts
The first time that I printed a round 3D part, I noticed that the shape had segments along the outer edge. Contrary to my expectations, the segments were linear, like an optimized circle.
I opened the slicer tool Cura to check if I could see the segments in my part. Cura did not show any segments, so this was not caused by my part. Also, I had successfully printed 3D parts with round edges in the past, so the culprit seemed to be the settings of the STL export.
I created 3 test discs, each with a diameter of 70mm. I exported them with different STL settings. To easily identify each disc, I added the name of the settings and values as text on the top surface.
Angular tolerance (deg)
Default settings The first disc was exported with the default settings of NX11.
Lowest settings The second disk contains the lowest possible settings of NX.
Middle settings The third disc was exported with the values between the default and lowest settings.
As you can see in the photos below, in the default settings, the segments are visible. The disc with the lowest settings gives the best results: you can hardly see or feel the segments. The last disc still has some segments visible, but way less than the default settings.
Default settingsLowest settingsMiddle settings
Default settings side viewLowest settings side viewMiddle settings side view
Before you do an STL export from NX 11, you can turn on the option “Triangle Display”. This option will show the angle faceting of your STL export.
If you want the best results out of your 3D prints, you should experiment with the NX 11 settings. To change your settings:
For each export, change the default settings
To change the default settings for all STL exports, go to “setting gateway -> translators -> STL export”.
When you find that you have segments instead of round edges in your printed 3D parts, please check the settings of the STL export.
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