|Non-Manifold problems in Blender [message #60291] Wed, 16 January 2013 11:51 UTC
I just started on 3D modeling not long ago.
I have a problem with non-manifold with my 3d model.
I have identified the non-manifold parts in the model. However, I am not sure what is wrong with the model.
There are no "holes" shown by the orange dots.
Can anyone take a look at my model?
I have also attached the .stl file.
Thank you very much!
(Size: 4.09MB, Downloaded 80 time(s))
[Updated on: Wed, 16 January 2013 12:00 UTC]
|Re: Non-Manifold problems in Blender [message #60305 is a reply to message #60291 ] Wed, 16 January 2013 16:48 UTC
Get yourself a copy of http://www.netfabb.com/basic.php it's free|
Click on the red cross. You will see the yellow triangle is a hole and the orange lines are degenerated faces. These can be repaired. The part that is red on top of blue means you have faces on top of each other with no apparent thickness. This cannot be repaired in Netfabb. You need to give this area some thickness to separate the two faces.
It would be wise to overlap the three shells so Shapeways software will join them together as one.
(Size: 81.45KB, Downloaded 176 time(s))
|Re: Non-Manifold problems in Blender [message #60317 is a reply to message #60291 ] Wed, 16 January 2013 21:09 UTC
This is the best description of non-manifold I have seen so far,|
" In short: your mesh is manifold when all vertices are connected with edges and those edges are connected to exactly two faces.
ctrl+alt+shift+m tries to select non-manifold parts of your mesh.
Those parts could be: loose vertices, double geometry, inside faces/edges, holes."
Coplanar faces, separate meshes and ngons can also lead to nonmanifold errors.
A good way to check for overlapping faces in Blender is to go to the property panel/object data and unclick double sided. It is similar to the red area in Jacants picture, except these areas will be darker compared to the rest of the mesh in Blender. This will also show incorrectly oriented normals.
When you select non-manifold and the verts get highlighted, you can swap to edge select to clearly define the holes,(should not be creating a plane)
Enabling the measure panel addon will calculate volume, surface area, will tell you if the mesh is nonmanifold and if ngons are present.The settings are in the Npanel. As is display normals.
Experiment with the select similar options for faces,verts and edges. This helps in repair also.
Was this a file from something scanned?
Have any questions regarding Blender, and need fast answers, you are always welcome at the IRC Server Freenode, channel #blender. As a bonus, several there have experience in modelling for 3D prints.