I read thru most of Randy Ferguson's excellent post on how to use Naval Jelly which is used to dissolve (surface?) rust.
The implication in that thread seemed to be that rust "convertors" didn't work very well?
It seems to me that they are intended for 2 different (but similar) purposes. I see naval jelly being used on accessible areas to remove surface and "flash" rust, while rust treatment would be used in all of the "nooks and crannies" to seal and protect? This might also be good for pitted areas?
My impression of the naval jelly is that you have to make REAL sure that you rinse it off very well, or any moisture later would re-activate the acid?
I have never used either of these products yet, but plan to do so quite soon. Can anyone confirm or deny my beliefs? I'd really like to do this right...
I did a little bit of my own research on these items at Permatex's website as well as pulling a couple of bottles of of the shelf at our NAPA store. Here is what I have found:
Permatex Canada uses NJ-1C (UPC 80594) as a part number for the 236 ml size and calls it "Rust Dissolver Gel".
"Contains Phosphoric Acid ..."
"Rust Dissolver Gel removes rust by powerful chemical action. Applies easily with a brush. Rinse rust away in just minutes. Adheres to vertical surfaces. Provides 24 hour flash-rust protection for priming, painting or other finishing."
Rust Treatment (I believe this to be the same as "Rust Mort" that several others have mentioned.)
Permatex Canada uses 81387 as a part number for the 946 ml (1 US QT) size and calls it "Rust Treatment" - "Destroys Rust!".
"Contains Vinylidene Acrylic Copolymer ... Barium Sulfate ... and a whole lot of other nasty-sounding stuff
... cancer-causing, birth defects, reproductive harm..."
- Destroys old rust and prevents new rust.
- Can be used with body fillers and fibreglass
- Dries to a tough protective primer coating
- Seals and protects metal.
There is a lot of good information in the directions as well, but I don't have the time to type it all out right now.
Highlights (paraphrased in my own words):
Scrape or wipe dirt and oils.
Sand or wire brush rust.
Pour into seperate container, do NOT contaminate the unused portion - chemical reaction.
Brush or sponge a thin layer. Apply carefully, product will stain surrounding paint. Remove splatters with water and detergent immediately.
A black coating will appear in 15-30 mins, apply a second coat within 20 mins.
Allow 24 hrs protected from moisture before topcoating.
Acrylic Latex paint requires a primer/sealer before painting.
Laquer/Enamel may be painted without a primer.
AUTOMOTIVE APPLICATIONS: Allow an extra 24 hrs drying time before topcoating. Use sandable primer and 120 grit paper before topcoating.
Thanks for taking the time to read all of this, and all replies, comments, and advice will be greatly appreciated!