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offset surfaces fails; WEIRD


New member
Hi guys,

I'm quite new to Rhino, but I have a very weird problem here; I have this simple geometric shape, a pentagonal cupola (PIC A) which I want to give a thickness of 5 mm inwards.

I have tried to offset the surfaces all together and separately,they overlap then of course, so I splitted each surface with every surrounding surface.
Then I thought this would result in the inner shell I want to create, which SHOULD look exactly the same as PIC A, but it doesn't, if you zoom in closely on one of the bottom corners this is what you see!! (PIC B)

if I measure the offset afterwards, it measures 5.1mm instead of 5, i don't understand it...



New member
Hi Viskes,
do all surfaces have the same angle related to the surface on the bottom? If some of them are more steep than the other, the edges can't match up. I suspect that being the problem.
Did you offset the bottom too?