SW2004 POINTS, RELATIONS AND DESIGN TABLES

I am having a bit of frustration with a design table driven part. The part
itself is a helical sweep of a rectangle. The rectangle is related to to
helices by a pierce relation to points. The design table changes the
diameter, pitch and number of turns of the helices. Pretty simple actually.
What seems to be happening is that the point on the sketch that is related
by a pierce to one of the helices seems to change from one corner of the
sketch to another depending on which configuration is active. Change seems
to be brought on by reopening the part. This problem also occurs with the
mates to the sweep. The corners seem to renumber themselves internally so
that the vertex I used for mating one day will be switched to a different
corner of the helix cross section the next day or time I use it.

Has anyone else seen this kind of behavior? Anyone found a solution?

 

The rectangle is fixed at 1 inch wide and changes height by its relation to
two helices to which it is related by pierce relations at the corners.

The parameters that change are the diameters of the helices, and the pitch
of the helices. Pretty simple really. I had stepped through the different
configs several times when I created it and not always in progressive order.
There wasn't a problem till I edited the DT and changed the pitch and number
of revolutions in the helices.

There were vertical and horizontal relations on the rectangle, but I have
since removed them in favor of parallel and perpendicular.