Definitly watching this one closely, great start!
Just one question, what is an oxalic bath?
For the powdered type (which is like Comet or BonAmi) you can buy
Barkeepers Friend. Anyhow the active ingredient is oxalic acid. This is for stuff you actually want to scrub.
If I want to wash an old patina without removing any solid paint I will use CLR. But I don’t do that much because I like fresh shiny paint.
I think “patina vehicles” are interesting to look at, but I don’t want to own one.
The oxalic acid is terrific for removing water spots from glass aquariums, which is why I buy it.
I have a big bottle of swimming pool cleaner, which is phosphoric acid mixed with soap, and I use this for stuff where I want the rust to blacken. it’s also great for taking the rust stains off your concrete because it literally removes a layer of concrete. You can use it as a paint prep if you degrease afterwards.
If you have a slippery concrete walk, you can roughen it lightly by applying phosphoric acid solution and then washing it off with water.
Before painting fresh metal I usually use Jasco metal prep, which is a solution of phosphoric acid alcohol and water. I think they changed the name a few years back and it is called Jasco prep and primer now, but I have used this for 40 years.
Even if you sand metal it can have rust in the pores that you can’t see. This converts the rust in the pores to hard, black, iron phosphate and rusty pinholes will not pop out later through your paint.
Don’t get that stuff in your eyes folks! It takes the skin off your hands fast enough, So take the necessary precautions.
