Repair mesh hangs

[WhiteRoomSkis]

I'm trying to create a body from a STL file. After opening the file it shows that the mesh is not closed. When I attempt to repair this file within fusion, the repair mesh function hands at ~75%. I have tried this several times with the different methods. None finish. I have turned off all of the graphics enhancements thinking it was my Mac that is the problem.

Am I missing something or is F360 just really bad at this? 

I have download blender but I have no idea how to use this program. I did get as far as getting into the mesh workspace and using the fill holes function. However this did not work either after importing it backing F360.

Can anyone help me out with this file? I need to ge this to a solid so I can machine this and give the customer a sample. I have attached the file incase anyone want to have a look.

[TrippyLighting]

If you want to directly machine the mesh in the CAM environment I am not sure mesh repair is needed .A conversion directly into a solid boy will likely fail, even if all problems are repaired, because with 1.3 million faces this is too large of a mesh.
reducing the mesh is also not a good idea as it will eliminate detail.

What exactly are you trying to achieve ?

[WhiteRoomSkis]

I figured out that there were too many faces. I reduced the faces significantly, got it to repair and to convert into a solid body.

This file was sent to me by a friend/customer. I need to machine a bunch of these from wood for his door trim corners. I don't normally do a lot of 3D machining. Most of my work is 2D so this is a bit of a learning curve for me.

Any suggestions on which tool path would be fastest with this type of work? I was able to get a 3D parallel tool path to generate but it is 30 min per piece at the highest recommended feed rate for the tool ( Amana Spectra 5.4 deg tapered ball nose).