what is the media of choice these days? - soda? - i have heard stories where people find sand in knooks and crannies forever - is that still a problem?
is it an option to have a car dipped to strip it? - like you might do to a frame?
thanks
For the underside using a DIY pressure pot; Red Garnet or Aluminum Oxide. However PSI and tip size needs to be adjusted lower. Its aggresive but re usable once filtered. Coal slag (black magic is pretty good also. But then you are exposed to coal dust and it eventually breaks down as sand does.
Sand breaks down fast turning into Silica dust. Its bad for you to breathe and you really need a respirator air filtered mask. Also it is heavier, making it harder to get out of confined areas.
For outside metal, use plastic media. I don't recommend dipping because the sealer (dum dum) in between the panels is washed away. Kind of an expensive route besides.
I did mine on the underside. It took 2 days and kicked my a$$. I used plastic tarps to confine it so I could re use it. I don't think I would do it again unless I got paid well for it.