My assignement evolves around the strength and stiffness of a structure of agricultural machine. I included the shafts in the frame analysis because i expect they have a significant effect (i could easily exclude the shafts and not have this problem at all). The shafts are attached to the frame with self alligning ball bearings which I simulated with two spheres, one is attached to the end of the shaft and the other one to the frame. They moved freely in the assembly, everything was fine, but when I did the analysis (static study), the spheres just won't move in relation to each other as expected because of the shaft flex under it's own weight. I tried defining the bearing connector but the manager won't accept the spherical faces (even tough the Solidworks Help says it should).

I tried following this video:

http://www.youtube.com/watch?v=NKlz39qWSz0

I deleted the inner ring of the so called spherical bearing (just a hollow cylinder with the outter wall shaped like a part sphere)

I supposed that clicking on the button for Self allignement would solve my problems but i get the message "Material not defined for one or more shells" which from past experiences could mean a bunch of problems in the model, one of them could be the gap in my model, which i clearly have, because i erased the inner ring. But the model in this video also has a gap and it is supposed to work.

I also tried with cylindrical faces instead of spherical to fill the open space between the shell of a shaft and the inner surface of the outter ring but the same error massage is still there.

I'm now pretty lost and i haven't found any similar problems anywhere else.

I attached the model (I have 2011 version).