Rust Removal With Phosphoric Acid

[Ulma Doctor]

i have only used naval jelly, it leaves a white colored finish after rinsing off.
i like the idea of an acid soak!
thanks for posting all the info guys!

 

[jim18655]

Some tile and grout cleaners are phosphoric acid.

 

[Ulma Doctor]

I really like those compound calipers you have there Micke, i have not seen any like them.

 

[John Hasler]

Is it just a soak or is there any scrubbing/wirebrushing involved?

I wire brush any scale and of course the object must be completely free of oil or grease. If you want the patina do not scrub or even wipe after removing the part from the acid. Rinse it and let it dry.

Sometimes I take the part out, scrub it, and then put it back for more soaking.

 

[ch2co]

I really like those compound calipers you have there Micke, i have not seen any like them.

Thanks for pointing these out, I was so awed by their patina, I was blind to what parts I was really looking at. Those are some mighty cool calipers, I want them!

Chuck the grumpy old guy

 

[RodSME]

I've been using a product called Ospho for years. It's a phosphoric acid wash. I've had a quart bottle for some time and it is about gone. I basically do the same thing Micke S does. First, I make sure the part is free of oil and contaminants. If you don't, the result will be blotchy. Then, I use Scotch-brite dipped in the Ospho and scrub the rust if there is a buildup. If there is a thin film of rust or none, I just wet it down and leave it for an hour or so. Afterwards, I wipe off the liquid till its dry. You wind up with a nice grey finish. Make sure you wear eye protection and nitrile disposable gloves. I live in sunny, humid Florida and my shop is in the garage. With this coating, I don't have a rust problem. I do the top of my table saw, drill press, etc., even my Jacob's chuck. I also do my hand tools.

As I remember, I bought the Ospho in an auto paint supplies store. I visited the West Marine web site and they have it for sale too.

http://www.westmarine.com/buy/ospho--rust-converter-metal-primer--P012222196

 

[Plas62]

Do you use the phosphoric acid at 100% strength or dilute it with water?

 

[John Hasler]

Do you use the phosphoric acid at 100% strength or dilute it with water?

I dilute mine, but of course that depends on the concentration of the particular product.

 

[Uglydog]

All,
Thank you.
Likely less expensive than the alternatives I've been using, and perhaps more effective!!

Daryl
MN

 

[RodSME]

Do you use the phosphoric acid at 100% strength or dilute it with water?

I apply it full strength.