A typical question people looking for a school stage ask is: Should we buy the heavy duty versions of Cameo because we are going to have fifty people performing on the stage at the same time? To which we answer, Standard Duty Cameo is more than adequate. A full cast of Oliver is exactly the sort of load we expect to be applied to one of our portable stage systems. It is only when you have something out of the ordinary, such as a full size concert grand piano, that you need to consider heavy duty Cameo. Standard Topdeck Cameo is strong enough for most demountable staging applications.
However, I hear you ask, how strong is strong? Unfortunately it is difficult to answer that question without getting a little technical. So here goes…
Structural calculations, carried out by an independent structural engineer, demonstrate that standard Cameo will withstand a force of 5 Kilo Newtons per square metre. To put that in plain English, because a 2×1 metre Cameo has a surface area of 2 square metres, it will carry 1 ton.
To put this into context, to get anywhere near the weight limit of a Cameo Platform, you would need to get around eleven people, each weighing 15 stone onto a single stage platform. Which would be difficult, even if you were creating human pyramids on an area of two metres by one metres. It is very difficult to put sufficient people onto a single platform to get anywhere near a ton.
Then why bother having a heavy duty version then, if the standard is sufficient?
Part of the reason is that standard duty Topdeck flexes slightly but unless you are looking for it, it is possible that you would not even notice the flex. For most school stages the spring is an advantage, as dancers and other performers love the similarity in the slight springiness, to the effect of a sprung floor. However there are those who prefer something a little stiffer.
Instead of having two intermediate beams running the short way, the heavy duty Cameo has two beams running the long way. Because these two longer beams pick up on the strongest point, they reinforce the weakest point.
Back in the real world of “No such thing as a free lunch”, the two metres of additional aluminium add both cost and weight to the heavy duty Cameo when compared against its standard duty brother.
5 Kilo Newtons is the standard required for demountable stages by the regulations. This is interesting as the floor underneath only needs to have a strength of 4K Newton, while the floor of a multi storey car park 2K Newtons. Having said that, the regulations rate the floor of a library at 10K Newtons. So maybe it does all make sense?
For those of you who want a more technical definition of a Newton: – A Newton is the force required to accelerate 1Kg at the rate of 1 metre per second squared.