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Advice on STL Creation - Tips on how to solve missing STL faces

Let's talk about the potential problem of missing faces in STL files. Note: This article is not intended to be a tutorial how to use the custom stl settings and their functions.

It has been shown that even in geometrically simple shapes, sometimes there are missing stl faces.

Inspection of such failures has been shown to be because of maximum extreme custom stl output setting parameters, of both Deviation and Angle.

Note: The stl result is dependent upon the shape and aspect ratio of the body and not just the minimum setting of Deviation AND Angle.The below example shows that both extreme setting of Deviation and Angle can be used.

How to determine a Custom Deviation and Angle setting if Course, Medium and Fine are not suitable without causing missing faces?

One method is to divide the Fine setting of both Deviation and Angle by a similar factor.

This results in a MORE proportional even fine mesh all over:

Note: Results varying depending upon the body shape as shown below

The above advice is not to set both the custom deviation AND the custom angle to their minimum setting - in general there is absolutely no need for such settings and in certain shapes ( not all) , the maths can not be resolved for both values set at custom minimum.

Note: this advice is specifically tailored towards not setting extreme values of 'Custom setting' - an ultra fine setting can be obtained by the equal division of 'Fine' setting for both Deviation and Angle parameters. Divisional factors of 'Fine' by x2, x5, x10 result in proportional ultra fine mesh.

STL's can be quickly displayed ~ Inspected for missing faces in the DesignSpark Mechanical Viewer

Note: This article is not intended to be a tutorial how to use the custom settings and their functions.

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