I want to convert a sheet metal part into a regular part.
I'm not sure why you would want to do that, but one option is to save it as a parasolid, then import it back into SolidWorks. If you still want editable features you can run the FeatureWorks feature recognition.
You can model features on top of the sheet metal part and change it to normal part.
Any specific reason you want to do that? Can you instead model it from scratch as normal part.
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