Wow, this is a complete revelation to me. I just went to try it and it works. It was able to work even on primary planes. I was not aware that the replace face command accepts planes. Thank you for this!
Another very useful video. I don't take advantage of the surface workspace nearly enough. Workflows like this remind me that I'm missing out and need to keep it more front-of-mind.
Thank you. I tried to do the case study myself, before watching your video, and succeeded. Then I watched your video to see how you did it. Although the end-result is the same, your approach was more simple and effective. On top of that I've learned a few new things. Great fun!
I made 3 profile sketches to make a surface loft and it made the curve and profiles match the drawings really well. Then I thickened to the outside since that's what the drawing indicated, extruded faces that were too far in on the top curved portion and used split body (planes as tools) and remove.
For me, The green and red part can be modeled in 3 tools: Extrude for blue. extrude for red with flat surface, and sweep for the curve. Then I will do plane cut and merge the parts.
I commented on this before but put a link in the description so I don't think it showed up. I like the technique you used here! Very clever as long as it isn't to be sheet metal(which you state). One other method that could work depending on the design intent is to extrude the bottom, sweep the top and then loft between the two of them. It is hard to tell from the reddit drawing what that intersection should be.