[bill south]

Hey Guys! (Also posted on Bobcad Forum) This is Version 23.
Another problem. I imported an STL model of a Crest inside a dish which is "sunk" in a square Z plane. I want to delete the square part and end up with the circular bowl and crest carved on the interior of the bowl. I attempted to get rid of the square part of the model by creating a cylinder the Id of which is the OD of the circular part of the bowl intersected midway through the crest on the z plane. I then attempted a boolean subtract to get rid of all but the bowl. It just won't do it. It seems to be doing something then back to the original screen. Nothing changes. The two solids (cylinder and crest model) remain unchanged and are still two separate entities. I even tried a boolean add and still not luck. Nothing changes.
I'll attempt to add a zipped file of the model and any help will be appreciated.
I can't believe that this software won't do an easy subtraction.
Thanks in advance.
Bill

[mcphill]

I don't think you can use Boolean tools on STL files. They are just surfaces, even if totally enclosed, on the "other" side of the face is a "hollow" part. They are NOT solids. Boolean needs solid parts to interact with.

[bill south]

Thanks mcphill. That makes sense!
Bill

[BurrMan]

STL's can be "solids" and defined so..

It's just that BobCads Geometry tools dont work on Polygon data. Only the toolpaths do.