Your example is starting and ending on the same curve. But even if I modify the sketch the "mid curve" intersects with the other 2 curves, so that does not solve the problem.

I am definitely out of my depth now...

I was able to get a smooth curve by using a loft instead of a sweep. Equal length vertical and horizontal lines at each end,
And use the original curves for guide curves.
I have no idea how "exact" this is...

I think SW saves it as a standalone automatically, with the mirror feature. You can check the properties of "Mirrorsym part" to check the file location...

As far as I can tell, you don't have control of that when adding the tapered flange to the rectangular one, or when using convert to sheet metal. However, if you create the tapered flange first and add the rectangular flange to that, this is controlled with the Auto Relief option in the Sheet Metal ...

Not sure if it is any faster, but I did find another option.

1. Flatten the 2 bends to make the frame flat. 2. Make a boss extrude the size of the whole frame.

3. Combine "Common".

4. Convert to Sheet Metal & Keep Body (x2) 5. Combine

Understood. I played around with the test a little more and I was able to get it to flatten if I created a Base-Flange that overlaps the whole weldment. Obviously this will depend on the geometry that you have in your model, but it might be an option.

I was able to get your test file to unfold by using "Convert to Sheet Metal", instead of "Base Flange/Tab". 1. Extrude your radius instead of Base Flange. 2. Combine all bodies 3. Convert to Sheet Metal, and select "Keep Body" 4. Combine, selecting sheet metal body firs...

Another option would be to update the standard views... As drawn view, Screenshot 1.jpg In this example, I selected normal to Front, then "more options" in view orientation, Screenshot 2.jpg Select "Update Standard Views", then select "Right" for new orientation, Screen...

We use Stencilia-A for through cutting.

https://www.dafont.com/stencilia.font