HeadTube design

[Stellite6k]

Question concerning head tube design in mountain bikes. How would you all treat the head tube, as a pipe/cylinder or as a hole where the thickness becomes irrelevant?

In otherwords how do you figure out the ovalization/collapse calculation for a head tube?

and does thickness of the head tube matter?

 

[yoyoyo]

cylinder with two moment arms attached to it opposing forces transmitted through the wheel/fork/headset bearing.