Info needed: Soda blasting versus Paint Stripper

[sth65pac]

Originally Posted by 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.

Yes, there is a paint that sticks to aluminium or ten.

With aircraft you need to use compatible paints not just anything or your plane turns into white powder. Most common up until recently was a form of zinc chromate, the greenish yellow paint you see in many aircraft. The chromate has been omitted these days and a two pack type paint is used. (this is a short version)

Soda blasting could be detrimental to aluminium, and you may find that the person undertaking the task was using plastic media which is commonly used on aircraft as it leaves no residue or creates a dielectric mixture. It also does not create areas of stress on the alloys - another bad thing with aircraft.

Also you need to be meticulous when using paint strippers on aluminium as many will cause entitlement (material loses its strength).

I have never used soda blasting as it does not remove rust, only paint. If you want to strip back a vehicle without damaging the metal then soda is the preferred method. The risk is the if you don't get it all out, you basically have a huge battery and the rate of corrosion will be massive.

in short: soda takes off paint but not rust. 'Sand' blasting removes rust and paint, stripper removes paint but may leave reside.

cheers,

Ian