RUST CONVERTERS (phosphoric acid)

[Kent B]

Once I discovered that there was a product category called "rust converters" I started to jump for joy. The how-to videos and demonstrations made it look like an excellent choice for putting an end to that ugly brown patina.

I have known about naval jelly since I was a kid and have used it on occasion to solve small rusty problems. When I started reading about "rust converters" I envisioned a space-age technology that must have been the newest invention to fight the war against rust.

What I found out after reading a little further is that most of these products are mainly "phosphoric acid" based chemicals. Further reading revealed that the age-old "naval jelly" is the same thing. It is just a thicker viscosity.

Now that I have put 2 and 2 together I am looking for the most recent or modern version of a "rust converter". Old time remedies are wonderful but they can be improved upon by technology. Unfortunately my "happy balloon" was deflated slightly when I found out that there was no "new" miracle cure for the age old ferrous oxide disease.

I have managed to pick up a couple of products that were available at the local hardware stores, TSC, and discount auto parts stores. My goal is through personal application combined with research on the internet forums to find out what will be my best choice for restoring my old Ford 1710 2wd tractor.
I found JASCO PREP & PRIMER at Lowes
and RUST KUTTER at Tractor Supply.
I ordered Permatex 81773 Rust Treatment from Amazon.com
I know that there are more out there so I would like to find feedback from other people and see what they are using.

The parts are in various degrees of rust but overall only approximately 10% (not counting the wheels) of my tractors surface is in need of rust removal. The wheels, of course, are the most heavily rusted areas. They will get the most attention. Other rusted areas will get their share of love but the feet will get double.

If you have any personal preference please comment. I would love to hear from you.

Kent B

 

[paulwestski]

Harbor freight sand blaster

Ospho is a green liquid. Can be sprayed on with an old windex bottle.

 

[Ted Summey]

Rust-mort, pricey but effective from auto parts store.

 

[bjr]

I second the Ospho. The company I work for uses a large quantity of this product. bjr

 

[patrick_g]

I use Rustoleum brand hammertone finish paint. It goes on over light rust (not flaky chunks falling off rust) without a primer and I have some I put on rusty square tubing used for columns to hold up a concrete porch slab from a patio 12 foot below. It is now 10 years old and looks nearly new, no rust showing, not defects in the paint coating. I paint fence posts with it and just yesterday an antenna tower. It is available at Lowes in quarts as black or silver. They have other colors in spray cans. I had some silver tinted as dark green as they could and it is a light aqua metallic green, kinda nice. IF you are looking at the "right stuff" it will say goes on over rust right on the label.

Years ago I used Rustoleum brand rusty metal primer on the keel bolts of my sailboat. They were exposed to salt water in the bilge. Several years later there was no corrosion. There had been corrosion (which I cleaned off) prior to painting with the rusty metal primer. It painted on looking sort of milky but the areas where there was rust turned purple, so dark that it looked black (may have been, it was hard to tell.) It it stays corrosion free when constantly varying from salt water immersion to drying with salt residue for several years then it is good stuff.

Past

 

[Kent B]

Harbor freight sand blaster

Ospho is a green liquid. Can be sprayed on with an old windex bottle.

I have a small sandblaster, I forget the name, but it has a siphon type vacuum that takes away from the air pressure. I might just hook up the vacuum hose to my shop vac. and use all my air pressure for blasting. I have a 60 gallon husky 240v that puts out a high cfm. I picked up a bag of black-diamond today from TSC.

I like the idea of the thin liquid treatment like Ospho and the others. It looks like that would get down in the pores well.

 

[paulwestski]

Yeah ospho works real well and is relatively inexpensive.
We were building Navy hovercraft hangars years ago, and the cast iron drain grates for the the long trench drains had set out on pallets for a few months and had a ton of surface rust on them. We took a large rubber maid rectangular tub and poured five gallons of Ospho in the tub, and then dipped the grates and let them dry.
Once dry they had a small amount of white powder on them from the chemical reaction. We gently power washed them to remove the white powder. Once they were dry they had a nice black finish on them.

 

[newbury]

Check out Rust Remover Comparison Chart

 

[k0ua]

I have never used any of the rust removers, but I have used the rust reformer. It is a milky liquid you paint on rusty, but non flaking steel, it turns it into a black "something" I don't know what, and you paint the black compound. Works well.

James K0UA

 

[Egon]

Dairy Farmers use a product containing phosphoric acid to clean the milking equipment. Seems to worK for me on rust. It's probably one of the cheaper sources for phosphoric acid.

There are other acids that will also work.

Sandblasting cleans rust off but does not neutralize the interstitial rust. Means rust just starts again underneath the paint.