Wow! Thanks so much pbacot!
@pbacot said:
P.S. It looks like your rib may have a third surface or a double ridge--though the 2d drawings don't look consistent on this. And the section view has a complex profile. I used the plan drawing for my approach, with a single ridge, but I think the same approach would work if you need that detail.
Yes, there's a flat ridge at the top of the rib, the plan diagram does not show it well. There's a cut section of the rib showing the width of b and height h.
Here's another bar profile with 3 ribs and actual bar (with different profiles here) found via online search.
[image: 2-ribbed-bar.jpg]
[image: aANxat0.png]
Here's what I got playing around. The first is using your method, the second using Shapebender.
[image: 4sOItLn.png]