Its not just acid, its phosphoric acid, which is mild in the acid family. The stronger acids are very corrosive, so you want to stick with something strong enough to do the job, but not strong enough to be corrosive, and phosphoric fits the bill very well----as long as you get rid of the residue. Do a little search on the site.
There is a lot of water in it that evaporates and leaves the residue, so you have to stay after it to keep it wet. If you need it to stay wet on a vertical surface, you can cover it up with cellophane wrap and that will extend the time between rewetting it.
Some are reusable like Master Series, but are more expensive, and most are not reusable, like Ospho, Evapo Rust, and Prep and Etch
It works great after blasting to make sure all the rust is gone, and water wash and rinse after phosphoric is a lot safer than wash and rinse after blasting.
That won't rust any quicker than any other part of the car.
There is a lot of water in it that evaporates and leaves the residue, so you have to stay after it to keep it wet. If you need it to stay wet on a vertical surface, you can cover it up with cellophane wrap and that will extend the time between rewetting it.
Some are reusable like Master Series, but are more expensive, and most are not reusable, like Ospho, Evapo Rust, and Prep and Etch
It works great after blasting to make sure all the rust is gone, and water wash and rinse after phosphoric is a lot safer than wash and rinse after blasting.


That won't rust any quicker than any other part of the car.