I have studied this object, its symmetrical, it has to be as I used mirror to make one side from the other ! using 0,0.
the only difference (deliberate) is the feet holes.
I select the faces that are non stretch on the bends for extractSrf, ignoring the far rear bend, else it wont unroll, I flip result to get unrollSrf to give the right way round for my needs. To get the rear face’s other bend I do this again selecting the unselected bend this time. I join the two up and in the process of all this I spot that if I mirror the right across to the left using centre of top hole the webs are mismatched. They are the same widths, but out when mirrored. the top hole is bang on centre line.
There is also a sliver missing, yet as said one half is mirror of the other.
symmetrical item sees UnrollSrf create asymmetry.3dm (1.3 MB)
something wrong but what ?
file attached has the original solid on one layer, and left and right halves for comparison on two more, the extractSrf on the ‘on’ layer.
…and now I see asymmetry on upper web, yet again made with mirror, if one mirrors the result of unrollSrf on hole centre (which I have also moved to axis line , its a tad out. two minute kinks in the sweep, one I now fix with blend, mirror it to the other and they dont match.
Top web symmetrical with mirror sees asymmetry with unrollsrf.3dm (289.6 KB)
I do an experiment as I find UnrollSrf had items not same size or proportion, eg a simple rectangle becomes non parallel sides. I have now drawn what dhould have resulted as an accurate rectangle. Then to lay the sides up to it correctly.
I flatten manually this shape, and do maths on the bend circumference using extract isocurve and analyze length, I get 0.064inch, lay the upright down 0.064 out from start of bend. UnrollSrf the bend and it doesnt reach the surface, close but not there. Thus UnrollSrf is nor recreating the surfaces.
is this due to the micro sized edge found in this thread ?
UnrollSrf versus maths.3dm (97.0 KB)