Setmodelbound doesn't work(solved)

I create a box and attach it to some node but I can't surround it with a bounding volume.

Box b= new Box("box", new Vector3f(-hwid, 0, -hlen), new Vector3f(hwid, hgt, hlen) );

b.setModelBound(new BoundingSphere());



No surrounding volume is created. Why could it be?

I solved it too,

probably because of trying to set model before initialize method. I called updateModelBound in simpleUpdate again.