I was given something not unlike that many years ago. I lent it to someone and he bare metaled the back half of a 57 Ford Fairlane with it!
I had a Guyson cabinet, road compressor and did blasting for a while, when I went back to messin with motorbikes and needed to get parts beaded I stuck a window in an old plastic drum and used the "Lectrostatic"[make] spot blasting gun.
I have beaded loads of aluminium with it and now alumium oxide blast all the small parts I powder coat with it.
If you want to remove paint use paint stripper, unless it's something that can be grit blasted. Grit blasting[chilled iron] is very aggressive and removing paint off motorbike frames was like brushing dust off. Get a decent paint stripper and leave it to do it's job, then powerwash it off. Stripping cars[we regularly bare metaled cars] we used to scrape the stripper off the panel into a cardboard box, hopefully not getting it everywhere[when you walk it in house you get moaned at], leaving the pressure cleaning till we thought we had got all the paint off. If you need to scrape while your using stripper try wirewool. After washing the stripper off run over with a sander, to get the ghost of paint off and paint from anywhere you taped up, you did tape up the breather holes[so you don't get stripper inside the frame which then drizzles out on your new paint]..
I blasted the front panel of my land rover, I made a bag with a large poly sheet and blasted inside it; me outside everything else inside. I have even hung motorbike frames[ali ones] from the roof wrapped in a poly sheet and beaded them.
I have a land rover bulkhead to do, I am thinking of making a frame of scaffold wrapped in polythene as a cabinet and using crushed glass, I am told 3 quid at BnQ gets a big sack of it..
