No Intersection Found

Hello All,

Can someone explain why no intersection is found on model below?
It is clearly that both members intersect
The grey part is an extrusion and the other surface is an open srf

I have also attached the model
no_intersection.3dm (72.9 KB)

Any idea why this is happening?

Thanks in advance guys

This looks like a Rhino V5 bug that has been fixed in V6. --Mitch


i think that is a tolerance issue. Your model is 230000 mm away from the origin and your absolute tolerance is set to 0.00001mm. If i move the model closer to the origin without changing the tolerance, it finds the intersection in V5.