Roll cage tube diameter?

[Synchromesh]

Looking at camera mounting options (for track days) but just wondering what the typical diameter of the tubing used in roll cages is. I know there won't be one standard size, but what kind of range would be typical? In particular I'm thinking of that of a Caterham / 7-type-car full cage.

[Sam_68]

Check with Caterham, but from memory the minimum specification for the main tubes in an RAC-compliant cage is 45mm (1.75") diameter x 2.5mm (0.10") wall thickness CDS tube.

[Wild Rumpus]

Older cages tend to be 38mm, the newer cages go up to 50mm on the main hoops.

[Shaun_E]

Caterham FIA rollbar is 38mm and the full cage is 32mm - both vary slightly with the thickness of powder coating.

[Synchromesh]

Thanks. Does anyone know what the largest diameter I'm likely to find is? Do they get any thicker than 50mm?