[Godot 3] How do you add a custom collision mesh to an imported model?

Question

I created a really simple model of a knife in Blender, exported it using Better Collada, imported it, etc. What I have not figured out yet is how to generate or add a collision mesh for the model, specifically one to use with the RigidBody node (although knowing how to make a static one would be useful too).

If you want, here is the blend file http://www.mediafire.com/file/wf7q0ctb27yqw55/knife.blend

And here is the Collada file http://www.mediafire.com/file/4z8c1j79kgdl7cv/knife.dae

Answer 1

I figured out what I was doing wrong. I didn't realize that Godot treats imported model files as scenes. I was dragging and dropping the model file, not realizing I was importing the whole scene instead of just the mesh. In order to get the mesh I have to either open the model file in Godot by double clicking the model file, or I can right click on a node I want to add it to and use the "Merge From Scene" feature

Like so: https://gfycat.com/MintyLeanArawana

Answer 2

Comments

I actually figured out what I was doing wrong. I was unintentionally ignoring the core design system of Godot.

Everything is scenes, including imported model files.

I was dragging and dropping the model not realizing I was importing the whole scene instead of just the mesh. Oops.