Anyone have experience with Rust Doctor?

[Boomer]

Has anyone used this product, and what is your opinion of it?

[Brian Evans]

Boomer, I use the POR-15 equivalent which is just dilute phosphoric acid.  Accomplishes about the same thing.  It's good for surface rust but does nothing for structural rust.  It is good metal prep for priming, though.

Brian

[joemc7ab]

Brian / Mark

      I have used por15 upon recommendation from a friend.  I used it on the hitch platform and also the engine cooler. What I used is paint, not metal prep even though I coated over top for protection.
       Thusfar it is holding up well. It should because it is pricey.

                                     Joe.

[Larry_d]

Boomer
I have been using Rust Bullet, silver in color and brush on, works good to stop rust action. Haven't used it on anything that was rusted thru.
Larry

[gusc]

Walmart sells latex based Rust Converter in the auto body repair/paint section in small bottles, about 8/16 oz as I remember. It is not cheap by the gallon but large quantities will not keep unless used up quickly.

It goes by many names but it is all latex based which means it can be cleaned up with water before it sets up. After it dries it forms a very hard black crust over rust. It can be painted or not, doesn't seem to make much difference. There must be rust for it to work, it will not work on bare metal.

I used Naval Jelly (Phosphoric acid) for many, many years and it is nothing but a big pain - and it doesn't last.

Once I found rust converter I quit looking. Some of the newer names may be better, but I doubt it, and they are very expensive.

I use it on rusted battery boxes and fittings, the only thing I've ever used that stops that rust cold.

If it doesn't say it is latex based and makes a hard black crust I don't buy it. It is very thick and is easily applied with a brush or small roller. It also comes in spray cans but can thicken and become unusable in a short time. Wear gloves, it burns the skin and will burn into concrete floors, but is easily washed off with water.

Rustoleum never worked for me and a test by Consumer Reports said it didn't work any better than plain paint. Maybe it has improved, but I gave up on it long ago.

[robertglines1]

when you /where you can't get to it places  I have used diesel fuel forever on antique equipment. easy to paint over with oil based paint after initial evaporation.  I got ideal on River after watching them do it to barges.  FWIW  no scientific reason.  Let it soak in thru the rust,   Paint seals the smell  and future exposure.

[gusc]

Interesting, never heard that one. How long do you let it evaporate before painting?

For areas never needing paint I use the commercial aircraft corrosion preventive Corrosion-X.

It works great but is a heck of a lot more costly than diesel:)

[Boomer]

Well, I use Rust Bullet on all new metal and intend to do that here on the new sheet metal.  But the old crusty frame and cross members I decided to use Ospho instead of Rust Doctor.  Looks like they are about the same product.  Product evaluations say to apply with a brush or use a spray bottle then work it in with a scotchbrite and let sit till a hard black finish appears.  29.00 per gallon, plus shipping and will do a large area.

[gusc]

Boomer,

If it is cleanable with water before setting it is latex rust converter no matter what the name.

I noticed today in WM that Rustoleum has a small bottle of rust converter now in the auto body repair section that they call Rust Reformer?

If it is water soluble and turns to a black coating on rust it is all the same stuff and far better than anything else I've seen. Naval Jelly is worthless as any other phosphoric acid based stuff.