Tool Test-2
1- import the model
2- clear ( join ) the surface where the element will fail for min lenght
3- defeature the holes to prevent failing for minimum lenght
4- hide top of the manifold to inspect the inner surface
5- hide front half to inspect the inner surface and join required surfaces
6- do tria mesh
7- look for element failure and repair
8-define volume
9- do a tetra mesh