It takes a lot of power to move the pad the same way the porter cable moves it for instance-
the batteries to do that would have to be pretty big..and heavy..
Oh and using the air powered DA sander with polishing pads on it sucks compared to using an electric DA- I think it's taken two days for my compressor to cool back down from just doing one fender. It is 5 hp and runs non stop and still I have to wait for it to catch back up. Plus the oil drips from the DA and slings all over- water comes out too.. Alot of waste in the compressor- air tool system.. I guess it's all lost as heat due to compressing the air??
Whatever the case- just got tired of it and bought a pc. Glory!
But if you are going to blow into the hose, then you won't have to worry about the bulky loud hot expensive compressor. :wavey