Do smaller blasting pressure pots need less CFM?

[gasket999]

Just about to order a pressure pot for some small jobs - in the future I'll use it in a room of some sort (had three property sales fall through now - each with significant workshop potential) but for now, stuck in a single garage, so after knocking a 3"x2" patch of inaccessible rust off the bottom of my truck, I'll probably just shove the nozzle through into a makeshift cabinet.

Air is limited.- currently have a 3hp/50l belt drive but do have a spare boss on the garage airlines to let me add a second compressor if I need it.

So, does a smaller pressure pot use less air than a larger one - or does the storage capacity not make any difference to CFM requirements? Assuming it does make a difference then I think the smallest on the market is a 5-gallon, unless anyone has seen anything more compact? I'll go and buy one when I hear back and then will stark making up the upgrade components that @brightspark recommended.

Thanks.

 

[optima21]

when its being used it will make no difference, but when you connect the blasting pot a smaller one will take less time to get upto blasting pressure than a larger one. once its got upto working pressure it shouldnt make any diffence as the pressure pot is like adding another receiver to the compressor

 

[Brad93]

CFM is calculated by taking the orifice size and psi you're feeding to the pot.

 

[brightspark]

a 5 gallon pot will hold aprox 25 kg of sand which is well plenty for doing a car wheel etc .any bigger will take some filling up to pressure before you start blasting and reduce your initial storage pressure in the compressor tank best using a 2.0 mm jet for a 14cfm comp a 3mm would run nicely on a twin comp setup at 28cfm at 9o psi. heres one i made for a mate and one of mine finished