Can't Join Objects to Make One Single One

[Kent]

I was hoping someone in the community could help me out. I've found a design for some 3D printed Mickey Ears that I really like that I'd like to import into Tinkercad. The problem is the file has too many pieces and Tinkercad won't import it because it's too complicated. I've tried to join in AutoCAD, but I'm a novice, and when I try, it finds errors and won't join everything into one, simpler, object.

 

If anyone could give me some pointers or help me out, I'd really appreciate it. I've attached two files, one where I grouped all the objects, hoping it would then join (to no avail), and the other one is everything separate.

 

Thanks in advance to any who could offer assistance.

 

-Kent

Blank Ear Grouped.dwg Blank Ear.dwg

[Cad64]

That's just a collection of 20.000 individual 3D faces. Not much you can do with that. Maybe someone else might have some ideas, but if it were me, I would start from scratch and create the object as a 3D solid.