Man, I'd like to print this after some tweaks, but it's fighting me... and when trying it as 2 different sections splt along the right datum plane, I can see why because it will ONLY thicken one half one way, and the other half the OTHER way. I think I might have to create each surface offset from this "center" one individually, and no, the "offset" command doesn't work either. I'll get it....eventually. 😉 Hmmmm..
I suspect the surface may not be orientable in a mathematical context. Check out the link to a classic example of a mobius strip below. You may be able to analyze this with a field point if you have BMX.
At first I thought that might be it, but I've already thickened Mobius strips, and I was able to thicken my ArAnCa Loop, which is my take on the Mobius strip and is also one-sided. Since I was able to do both halves independently, in opposite directions (sort of), I think what's actually happening is the surface is inverting on itself. Try taking the STEP file, cutting the quits in 2 halves down the right datum, and thickening each, and you'll see what I mean. I think I'm going to have to build it out of surfaces manually, then solidify it.
These kinds of shapes just fascinate me and I'm going to start making polished bronzes of them through Shapeways, I'm hoping to start selling them thru there.
If a single sided quilt is split into more than one piece it will resolve the orientation issue. Looking at your model there is a sharp point that will not work for offset of the surface. I trimmed out the problem area and it will thicken as a single quilt, not what you want but at least it confirms the area at the center that is the problem for offsetting the surface.
See the step file.
Yeah, that was the area that seemed to give trouble. So I was going to build each of the surfaces separately and merge them, then solidify it. I'd had to step away from it to do something else so I didn't get to play with it beyond making the original shape. But in looking at your file, you gave me a better idea. Instead I'm going to trim out that area but keep it, then thicken rest of the quilt symmetrically, then patch just the center. Thanks!