I'm currently writing a computer simulation (in Java) of the formation of a helix from a spinning thread. The analogy I use is to imagine a piece of thread held between two fingers and left to hang via gravity. When the thread is spun by rolling one finger against the other, the thread will itself rotate. But because the force is only applied at one end, there is a delay in the time the force reaches the free end of the thread. This will result in a twisting effect and a 'wobbling' effect. It is this action which I wish to recreate in the formation of a helix. Does anyone understand what I am talking about? It's the fundamental modelling of the formation of a helix from a spinning thread. I need help. It sounds easy in practice, but tricky when you try to write a computer program. I come from an astronomy/computing background, and would appreciate the input from materials science people.