Missing Parts When Sliced

[christhetech131 0]

Hello!  I'm new to 3d printing in general and I was attempting to build a Jane Foster Helmet (STL Attached).  When I slice it I lose sections of the build.  Can anyone advise me how to fix it?  I've tried adding custom supports to the build in different configurations and have been unsuccessful getting this to print.  I've been doing tiny models to test with before building a full scale model.  Thank you in advance for your help!

Jane Foster Hollow.stl

[GregValiant 1,250]

There are a couple of things happening.

When you open a model and the "Model is not Watertight" warning comes up it means there are errors in the model.  Simple errors can be fixed in Cura using the Mesh Tools plugin.  More extensive repairs may require an on-line service.  A lot of errors likely means going back to the CAD software.

I thought maybe the walls were too thin, but it looks like there were 20 places where adjacent surfaces weren't joined together.

This is from the on-line service I used for repair:

-> Analysed your file:
--> 20 Naked edges (?)
--> 0 Planar holes (?)
--> 1 Non-planar holes (?)
--> 0 Non-manifold edges (?)
--> 0 Inverted faces (?)
--> 0 Degenerate faces (?)
--> 0 Duplicate faces (?)
--> 0 Disjoint shells (?)
-> Repairing: 100.00%
----- Repair completed in 209ms ------
-> Vertex count changed from 821 to 822 (+1)
-> Triangle count changed from 1620 to 1640 (+20)

 

This one seemed to slice alright...

1438609238_JaneFosterHollow_fixed.stl

[christhetech131 0]

33 minutes ago, GregValiant said:

There are a couple of things happening.

When you open a model and the "Model is not Watertight" warning comes up it means there are errors in the model.  Simple errors can be fixed in Cura using the Mesh Tools plugin.  More extensive repairs may require an on-line service.  A lot of errors likely means going back to the CAD software.

I thought maybe the walls were too thin, but it looks like there were 20 places where adjacent surfaces weren't joined together.

This is from the on-line service I used for repair:

-> Analysed your file:
--> 20 Naked edges (?)
--> 0 Planar holes (?)
--> 1 Non-planar holes (?)
--> 0 Non-manifold edges (?)
--> 0 Inverted faces (?)
--> 0 Degenerate faces (?)
--> 0 Duplicate faces (?)
--> 0 Disjoint shells (?)
-> Repairing: 100.00%
----- Repair completed in 209ms ------
-> Vertex count changed from 821 to 822 (+1)
-> Triangle count changed from 1620 to 1640 (+20)

 

This one seemed to slice alright...

1438609238_JaneFosterHollow_fixed.stl 80.16 kB · 0 downloads

This sliced perfectly!  I seem to be running into trouble getting it to be hollow to make it wearable.  I tried to remove the excess faces in the model and but that causes the watertight error again.  Any ideas how to remove the bottom face so it could be printed in a wearable size?  I appreciate all your help!

[GregValiant 1,250]

It would have to go back into a CAD program for that.  You could design an insert the shape of your head and export it as an STL file.  Then open the helmet and the insert in something like Blender or MS 3D Builder and subtract the insert from the helmet.  You'd really want to get it right the first time.

 

A second option is to go the other way.  Take a trip to Africa and visit a head shrinker and have him/her fit your head to the helmet.

It worked out OK for this guy.