Make solid or Unhollow

[Aaron Wintersmith]

I've got an STL that was optimized for SLA printing. As such it's hollow with drain holes on the bottom.

I'd like to print this with my FDM. When I import into the slicer it only comes in only as the shell.

What is your preferred method for making the STL solid again? I see Prusa Slicer has a "Hollow" workflow for moving from Solid to Hollow for SLA prints.

How do I do it in reverse?

[3D Printing Tips and Tricks]

Blender.

3dcoat

[Aaron Wintersmith]

Thank you that is a start.

I believe a workflow that's been discussed on the show before, to get to solid watertight objects, is to surround the target object with a larger solid, then boolean them. Like making a mold. Then you can reverse the process to get your object back, but now watertight and with issues fixed.

If this is an actual method discussed and I'm not mis-remembering, what is that workflow called? So I can google it and learn how to do it ... ?

[3D Printing Tips and Tricks]

Yeah I think that’s how my cohost does it with Blender.

With 3dcoat I load it as facets then switch the object to voxels make my changes then at a high resolution,. Export it out as an stl. This remaps all the facets.

[Nat Brooks]

My go to with this would be Blender.

I'm not sure the boolean process you mention would work as you would be cutting away the walls, but the void in the center would still remain I expect.

My workflow would be along the lines of removing the faces that make up the drainage holes so you have completely separated the inner and outer face sets. 

Then select one of the inner wall faces and use Control L to select every linked face. Then delete these. That will leave only the outer faces, but these wont be a manifold object.

You can create faces by joining vertices to patch the holes and this should then be a manifold and solid object.

Hope this helps.

[Joseph Larson]

Import into blender. Locate the drip hole, usually a hole on the bottom. Go into edit mode (Tab) and in vertex select mode (1) select all the vertices that make up the hole and delete (del) them. Then, while still in edit mode, Separate (P) the mesh->by parts. Then exit edit mode (Tab). Select the body that's the inside and delete it.

Now you have the outside mesh, but with a big hole in the bottom, so select the outside mesh, go into edit mode (Tab) and alt-select one of the edges of the verts you deleted to select the whole loop of them. (Alternatively you can select->by Trait->Non Manifold, assuming the rest of the mesh is watertight.) Then create a new face by pressing "F".

It's a little dirty, but should work.

Good luck!

[Joseph Larson]

If it's not a paid model, link it up to me and I'll make a video about the process.

[Aaron Wintersmith]

Thanks for the help guys I will give these a shot.

[Joseph Larson]

Whipped together this little video about how I helped Aaron out with this one:

https://youtu.be/4E0yI-shkUM

[Aaron Wintersmith]

Thank you Joe! I can't wait till I get some time and I can follow along.