Not sure why the post were deleted in this thread, but anyway after visiting Mr. MilHolland this past weekend at his house, I can see it is not worth trying to make the ribs from any other material than the Spruce, He handed me a Built rib and I could not believe how light it was and very strong, He said you can attach 300lbs to the bottom of the rib grab the top and lift it up, I do truly believe this it is stout, I imagine the varnish also contributes to the strength of these ribs.