You can join them like you show however at the end of the day you will have accomplished no more work in the sand blast cabinet than you would have done with one tank. Your pump can only produce so much compressed air in a given time. If you blast with your cman with only the one tank you can blast for 3-5 minutes and then wait 3-5 minutes for the system to recharge. If you add a second tank then you can blast for 6-10 minutes and then wait for 6-10 minutes for the system to recharge. So at the end of the day your minutes blasting and waiting are the same because that is all the pump can deliver. It is not the volume of air receiver you have that determines the work you can do, it is the size of the pump and the motor driving it. A larger tank can mask a to small compressor for short intermittent jobs but for blasting and sanding the tank size is virtually irrelevant
lg
no neat sig line
That pretty much says it all.
A larger tank gets you further the very first time before the pump kicks on, after that, it's back to the same old. So you would gain a *slight* advantage, but not worth writing home about.
tank size gets you longer pump cycles, and longer time between pump cycles.
Pump CFM is what determines if it will keep up or not (unless you're using a ton of air in a really short burst).