VUR4 describes the only legal raw stock as being:
Fabricated Parts must be made from legal Raw Stock. To be considered Raw Stock, the material must be purchased in one of the following forms before undergoing the fabrication processes listed in <VUR3>: Sheet Solid Billet Solid Bar Hollow Bar Solid Rod/wire/filament Hollow Rod/Tube
A typical building material noticibly absent is angle stock, e.g Aluminium equal angle.
VUR5: The following material types are not considered Raw Stock, and are therefore not permitted 1: Any otherwise-legal Raw Stock that has been post-processed by drilling, machining, or otherwise removing material. , e.g. Angle aluminium with regularly-spaced holes or slots
This wording demonstrates that an otherwise legal stock that has undergone further fabrication processes by forming holes is not permitted. However, angle is not a listed legal stock form so this seems to contradict VUR4's meaning.
Does this mean that angle should be considered a legal raw stock?
If standard angle stock is considered illegal, do teams need to demonstrate proof beyond cad drawings that the angle was formed by legal methods from legal raw stock, e.g bending sheet, milling bar or cutting square tube stock diagonally?