I have made a box using BRepPrimAPI_MakeBox(100, 100, 20);
and then I cut a cylinder from it (using BRepAlgoAPI_Cut) , and it worked fine and result looks like: http://www-hades.gsi.de/~biryukov/cascade/cut_primbox_cyl.jpg
after this I made another box from points (points->edges->wires->faces->shell->solid) and cut the cyllinder from new box(using BRepAlgoAPI_Cut). the result looked like bollean union. http://www-hades.gsi.de/~biryukov/cascade/cut_mybox_cyl.jpg
why could it happen?