drewing keep on stretching

i have a problem
i start buliding leg for my cut out character when i try to rotate the leg
in the scene planning window it keeps on stretching get long to the left and to the right

1)i am using the rotate tool to rotate it object after i place the pivot
2)i dont no why but it does it on some of the object
3)i build the model peg structue like its advised in your site
4) i am using toon boom 4.5

tnx alot for your help ;D