I had a look at this model as well and I see a lot of sheet metal "no-no's" inside it. For one, the use of cylindrical extrusions, which I would assume are PEM nuts? Those all need to be separate part(s) in the file/assembly, not a connected extrusion. If this was brought in from another system you will have a lot of work ahead of you as all that needs removed and then you will probably run into issues where the original designer didn't get the thickness consistent. Cleanup Utility will help you with that, but first those PEM's/extrusions have to go. Nothing will clean up or flatten until those are gone.
HTH,
Ryan
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Ryan Gudorf
CAD/CAM Supervisor
Budde Sheet Metal Works, Inc.
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