[Andrew Rowe]

I noticed the other day a guy soda blasting an aeroplane, so obliviously there
must be an etch prime that will stick on alloy. Typically when sandblasting you are looking for a 25 micron "pitting" (surface ) for the paint to adhere to. If you use coarser media , like garnet or steel grit you will get a deeper micron finish, before painting.