building helix in 3D

I am looking at building a helix(coil shaped structure)) in 3D in Away3DLite in flex. I have 开发者_开发问答access to basic classes like cylinder, cube etc. Can I extend these to get the helix. While I understand I need to essentially increase the y dimension as the angle increases, struggling to determining how the vertices need to be defined to render in 3D

Any pointers will help... Thanks again

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we managed to review the primitives already provided and charge the torus primitive to get what we wanted... wasnt too many changes

I am happy to share our changes if someone else has the same issues