Attached Link: 3D Printing with Shade 3D Printing Assistant

[Shade 3D](http://mirye.net/shade-3d "3D Printing with Shade") (even the cheap Basic, which is currently $49 on sale) has a 3D Printing Assistant that checks models for problems - then provides tools for automatic fixing. There's more to it than just sealing off open geometry.

There is a downloadable demo too if you want to just check it out.

Best regards,

chikako
Meshbox Design | 3D Models You Want