Available in TurboCAD Platinum only
A crease is a sharp edge in an otherwise smooth surface. Creasing allows you to combine nice smooth curves with hard edges to make more realistic models. Any edge can be set to be creased. You cannot Crease if the Edit tool is in Selector Mode.
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Once you have your edges selected specify the desired Crease value in the Inspector bar and press Enter.
Since selecting faces also selects their associated edges you can also begin your creasing by selecting faces for the desired edges. This can expedite maters in some cases.