3D Printing Causing Issues I have only recently started using Blender and have spent free time following the donut tutorial by Blender Guru. I’ve created my first model, a box to hold our remote controls

It all looked ok until I exported it into STL file for Prusaslicer - it looked horrible! Lots of red bits, split layers and a additional false floor.

 

When I went back into Blender I added 3D Toolbox and get a big list of things that I assume I need to resolve to allow me to print successfully. 



With such errors like
- Non Manifold Edge
- Bad Config. Edges
- Intersect Face
- Zero Faces
- Non-Flat Faces
- Thin Faces
- Sharp Edge
- Overhang Face (I suspect these are ok as they are probably lettering etc)

My question is how to resolve the issues?
There is a lot, you can check before printing.

-triangulate faces to make them planar. Go to edit mode select all and triangulate

-check if the normals are as they should be, by turn on face orientation in viewport overlays, any red is a bad sign.

-You can turn on a 3D-print addon where is an option to make manifold, also when in edit mode under mesh>clean up there is a few tools that deal with bad geometry.

-ultimately, which iam using when working with a chaotic and more complicated models, there is an awesome voxel remesh. When you set a right voxel size (by try and error) it makes your model clean for print, but in hight mesh density, so I usually use a decimate modifier after that, to make it more "light" to work with.



In your case, it needs some repairing after the boolean. I went to edit mode selected all and triangulated faces. After that I used 3D-Print add-on and clicked make manifold. it did some cleaning. I think it should print completely fine.



Not all warnings are dangerous for print. Like overhangs, it just informs you that there is a place that needs support. Or zero faces - the size that trigger the “degenerate” test to result in that, if you would select all your mesh (in edit mode) scale it and you’ll see the toolbox will not find any “0 faces”. Problem could be intersecting faces or non-manifold.