Why Can't I slice Wheels or Rims face up without getting a plug/disc covering it?

[turbonium]

Thanks Guys! I was able to fix my sketchup wheel Kris_Wheel and also fix other models with the Microsoft link...

https://modelrepair.azurewebsites.net/

I'll try to start getting familiar with the AutoDesk and other apps. Spent all day in Creo at Work, might as well just add another one to the pile.