Any ideas on flattening a surface with compound curves?

Whatever you do, don't let a CAD system do this for you. It WILL be wrong. (Pro/E could do this somewhat, but it was ALWAYS wrong.)

All of the stamping die firms I worked with had special software for developing flats of odd shapes. None of them would accept a flat pattern from outside (or customer) except for quoting purposes.

Flattening regular sheet metal bends is not difficult (for a computer). It is mostly simple algebra. Flattening compound curvature is far more difficult. It is a close cousin to FEA.

Unless it can be flattened by the SolidWorks sheetmetal function you need to look at a SolidWorks partner product like:-

John Layne

Any ideas?

Not without knowing the Guassian or mean curvature and what you expect of the flat profile.

Curvature on the part is approx 84" radius in the "x" direction (top view), and approx 44" in the "y" direction, on a part approx 12" long. Basically a potato chip. What do I expect from the flat pattern? Not much really. Maybe to fetch me a drink, bring in the morning paper, something like that. No, really, the flat pattern would be put in a form die to create the final part.

The part size, in relationship to the radius of curvature, is such that you might get away doing the following:

-Create 2 projected curves through the center of your part, one parallel to x, one to y so that you can measure their length.

-On a suitable plane for a projection, open a sketch and convert the perimeter edges.

-measure your distances in x and y at the same points your curve goes through.

-create a flat solid from the converted edges

-do a non-uniform scaling of the part ( ie for x, curve length/projected length... probably in the neighborhood of 1.05 )

That should get you pretty darn close, probably as close as most forming software.

Check with blankworks. You should be able to get a 14 day working demo to try out. We had an airfoil form that needed to be flattened out and blankworks was the only one that worked for us.