Thanks shr,

My next question is what will be the length of the rigid from 20 to 200?

Simple trigonometry will tell me that the length will be 762 / cos 45 = 1077mm.

762 = 1524 / 2 (1524 is the diameter of the header).

But when we input this length for the rigid, the 3D model doesnt look correct as half branch is outside the header.

Is this correct or I should calculate the length so that the model will show full branch which goes inside the header.

Thanks