# Ball bearing

Hi

I want to simulate a ball bearing (to do a rotor) but it doesn’t work very well…
I began a blend : http://www.mediafire.com/?22ywxwtgyaz
But the little plan is not parallel to the big one…It might be because of an error in the constraints, but where ?

I don’t really understand what you are trying to do, can you explain it a little better? What does a ball bearing do, and why is this not working well?

Ok, I’m sorry, I’m French… :o
“Ball bearing” is the google translation for “roulement à billes” in French… ^^

I tried to draw this :
![http://weapic.com/img/a37d49b8670233e14e2aeedc29fe2190_roulement a billes.png](http://weapic.com/img/a37d49b8670233e14e2aeedc29fe2190_roulement a billes.png)

The top plate turn with the central tree but the bottom plate is static.
My problème in the next blend is to rotate the little plane for the empties to be points of this plane (as much as possible).
So I tried to add four objects which are tracking to the empties and then I want to make the plane the normal of these objects…I used four copy rotation constraints with an influence of 1.0, 0.75, 0.5, 0.25. But it doesn’t work.

I think my explication is not good so I decided to show you my complete blend. It’s an helicopter rotor :

Use Alt+A to see that the ball bearing doesn’t work : the rotatable cyclic plate isn’t parallel to the static plate…

I think my explication is not good so I decided to show you my complete blend. It’s an helicopter rotor :

Use Alt+A to see that the ball bearing doesn’t work : the rotatable cyclic plate isn’t parallel to the static plate…

Edit : Ooops ! Double post ! :o :o :o