This Shapeways tutorial explains how to avoid 3d printing errors that occur due to the minimum wall thickness requirements of 3d printers.
Minimum wall thickness is defined as the minimum thickness that your model should have at any one given point.

In the case of the image above d=1 is the minimum thickness.
If you are designing a cylinder for example the cylinder itself should at all times have a larger diameter than 2mm. If you would turn that cylinder into a straw the edge of that straw should at all times be at least 2mm thick.
The minimum wall thickness depends on the material you choose. If you always want to be in the clear we recommend sticking to 2mm.
Here you can see the wall thickness of one of our Light Poems.
