Check the solidity of the model at the selected scale
Not thick enough
Thickness OK
The material you selected has a solidity threshold around mm.
Below this limit, the object may be fragile, and even, in certain cases, un-printable.
The preview on the left shows you where problems may happen.
Untick the checkbox on the left to de-activate solidity check.
Not for sale, just a test. Try the solidity test and you'll see the fences will snap off. From Schematics World 1. Created with Mineways (http://mineways.com).
