Here is a curve made with freeform command, which yields a good freeform sweep, but a bad flat sweep.
- Brian

Hi Brian,

You won't use 'Flat' option Sweep for such a shape, the 'Flat' option is mainly used to control or force a multi sided profile in either X,Y or Z direction along an axially produced rail.

For example; the attached file produces the opposite what you have Bad 'Freeform', Good 'Flat'.

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Hi

sometimes if your profile gets flipped or you select the wrong part of it the sweep does a 180 twist as if sweeps

I would try flipping the left hand circle with points on 180 degrees and see if it changes the sweep error





he is an example the centre circle has the wrong orientation






cheers
shayne