How-To: Fix Your Model for 3D Printing, Part 2 – When Netfabb Fails

[Update: Try using Blender]

Modelling for the physical world has its own set of constraints. Since I don’t focus on those constraints while modelling, I have to spent  time repairing the model for printing. Luckily, there’s netfabb, providing the one-stop solution.

Part I – In-Depth Netfabb

Part II – When Netfabb Fails

Unfortunately, netfabb is not a panacea. Here is a mesh imported in netfabb Studio Basic. The caution sign indicates it can’t be printed. Even after both default repair and simple repair have been applied, the caution still appears. It was uploaded to netfabb Cloud, and failed.

Netfabb Studio Basic shows the problem as invalid orientations of a lot of triangles.

Remove Non-Manifold Vertices:

If your model is composed of a large number of polygons, you can import the model into MeshLab, an open source tool for editing models.

To select all the non-manifold vertices and delete them:

Go to “Filters > Selection > Select non Manifold vertices” to select. The number of selected vertices will appear in the purple bar on the bottom.

Go to “Filters > Selection > Delete Selected Vertices” to delete.

After deleting all of the selected non-manifold vertices, some new non-manifold vertices may have created. Repeat the select and delete until no non-manifold vertices can be selected.

Export the fixed model from MeshLab and import it into netfabb. Another round of simple repair, (to patch any holes that might have been created),  should fix the model.

Viola!