Surface mesh and nodes association

Hi there!

Would someone please explain me one thing?

I have a complex solid model. I split it on parts. Each of parts have own plane of symmetry. So I split each one to mesh just half (quarter).

Then after surface mesh of half (quarter) I reflect 2d mesh to opposite part and associate nodes to it. After I try to mesh faces of the connected parts. But time to time mesher not 'feels' associated nodes. Often it not 'feels' associated nodes for edges with T-connections (works for only 2 surfaces of 3).

It makes me crazy...

Thnx in advance for answer.