Keep getting errors when trying to flatten certain edges and I don't know what to do.
The resulting edges (sheet-metal thickness) are not perpendicular with sheet-metal face.
EDIT: I added some screenshots for a different approach.
I would post file but it appears you are on an older version of Solidworks.
is that what you are looking for?
I removed the top cap and redrew it using the flange feature at a 45°.
but I wasn't sure of the part you were looking to flatten.
I also find it easier to organize the parts I would like flattened by creating a config of each and deleting the unnecessary bodies.
Retrieving data ...