Hi Ed,
>>My experience so far has been building and slicing solids.
You could build it by sweeping then boolean the swept surface from the extruded solid from profile. It can sometimes cause problems if the swept surface intersects itself within the solid, as that can cause failure. But as an example of creating that shape from slicing(boolean) from solid:-
We have the profile curves, I have the profile in 3 parts (which are for extruding the solid, and sweeping the surfaces to boolean), then have the profiles for the sweep positioned at the ends of the main profile.
Select the 3 main profile curves, and extrude to create the solid:-
I will first sweep along the top curve,.... so select the end downward facing sweep profile, and sweep along the top rail:-
Then boolean diff. The base object being the solid,... the object to subtract, the swept surface... You will only actually see the swept surface disappear when you boolean diff, that is because the surface that was used as boolean was open, so if you change view, you will be able to see that the solid as been sliced, you can then select the unwanted part and delete:-
Repeat that by sweeping the bottom 2 rails with the other end profiles and again boolean(slice) the solid, then delete the unwanted parts:-
If you where to instead just use surfaces, then you would sweep the profiles as you did above (sweep all 3), but rather than boolean them from a solid, you would use trim and trim away the unwanted surfaces.
Hope that helps, just ask if unsure or if I have not explained fully.
