Don't know how to explain this other than show you the outcome. It seems as if when I subtract the two slots, the render does not create the outside surface. Can anybody explain what could be happening here. Using TC 16 Deluxe and starting to get frustrated with it and may upgrade to Pro.
Please ignore the fact that there is a whole bunch of other stuff going on in model space. This was one of the first drawings I created while learning TC. Hopefully they don't have an effect on the drawing. If you delete all of them, except 0, but delete the contents on 0, it doesn't seem to change anything.
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