Make sure that in your CAD program that all planes or flat surfaces have a minimum of a 3mm (0.125”) thickness. We generally target 4 mm (0.188”) wall thickness, but this varies depending on where in the model the feature is. If thin planes are printed they make it impossible to handle the model without it falling apart.

Below is a picture of table that only has a plane for the top surface.

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To correct this problem, simply extrude that surface to a minimum of 3mm according to the scale of your overall model construction.

The picture below shows a polygon being extruded to a desirable thickness.

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