# Meshmixer create solid

I have this .stl that I downloaded and I need to create a solid of this 3D. However, if I click "Make solid", it doesn't work.

How can I do? I think the problem is the black layer but I don't know how to resolve.

Before make solid:

After make solid:

I need to make solid and the black layer is deleted when I do it.

PS: The other object are different item, so if they are there or not is the same

• Hi and welcome. We may require more information, please edit and add more details. Jun 19 at 13:39
• Other? I have download the file, I don't much more but I need to make solid and the black layer is deleted when I do it Jun 19 at 14:46
• Do you have a link to where you downloaded the .stl file from? If we can reproduce the issue, then maybe a solution can be found. Please edit and add the link to your answer (don't add info in the comments). Jun 19 at 17:44
• Your object browser shows three objects in the first image, only one in the second. Are the missing pieces those of the other two items in the first image? Jun 19 at 18:08
• The other two objects are different item Jun 22 at 7:01

# Make solid requires an enclosed volume

To run the make solid operation, the selected parts need to enclose a volume. In case the volume is not fully enclosed, the program tries to solve a solution that closes the open surface.

The black layer is most likely failing to compute because its normals are flipped. This means it does not enclose a surface, it excludes anything between the surfaces from being inside the body defined by it - it is everything but. This is solved as "this surface does not enclose anything, so I cut it out" but for where it creates a valid solution in the area of the white surface before the operation.

This leaves you with the white retained part after the operation.

# To fix this is an in-depth project

Fixing such errors is quite involved. You will need to do the following steps, depending on your program to alter:

• flip the surfaces so that it shows outside
• make sure that the body is closed, possibly by adding missing surfaces
• How can I enclose volume? Jun 22 at 13:09