There is no error in plan in 16 but there is in 3D (see attached image).
It seems to be a problem with the geometry when the radius is exactly the same as the length of the sides.
Make the radius 0.1mm bigger or smaller and it works.
Making the length of the horizontal side slightly different doesn't work but oddly enough changing the length of the vertical side slightly does.
And it only seems to be a problem with the mesh too - fill and slab are fine.
Barry.
One of the forum moderators.
Versions 6.5 to 27
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