STL output from CAD turns curves into polygonal curves. When you export the stl file from your CAD software you have to set the polygon size smaller. Look for options on the STL export...
Unless you're using SketchUp (ugh!). In SketchUp circles are polygons right from the start. You can specify how many sides a circle should have when you draw it. This is one of many reasons why SketchUp sucks for 3D printing.
Edited 1 time(s). Last edit at 04/07/2017 08:36AM by the_digital_dentist.
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