Hi Michael,

I'm trying to play around with this meshing problem.



Trouble only happend here if:

a,b,c are G2 witn a bulge of 0.25 (for ex. 0.3 doesn't show any problems)
1 and 2 must be G2 too (I only tried with a bulge of 1 so far) , because in G1 there are no problems.



Increasing the mesh angle inscrease the number of artefacts.
It happends whathever the output are tris, quads-tris, or ngone

Not sure if it's helpfull for you.