thank you Hillel. It´s good to have experts like you in this mailinglist. I will update my homepage with your method soon ... BTW. I have tested the stability of a bent crank and it was as stable as the unbent one. Maybe I was just lucky. Regards, Jürgen. ============================================================ This is the Python Mailinglist at freelists.org Listmaster: Juergen Mages jmages@xxxxxx ============================================================