Parting surfaces
You have to select the surface or surfaces that you are going to use to create the cavity blocks. You have the following options:
Select ALL SURFACES (meaning parting surfaces).
SELECT A COORDINATE SYSTEM . Very useful when the parting surface is totally flat. You have the possibility to select directly CURRENT COORDINATE SYSTEM.

If you decide to create the cavity
blocks with a separation by coordinate system you will not have to build
the parting line.
Select manually Select the parting surfaces
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