81773 Rust Treatment, 16 oz.

Stops Rust in Its Tracks I’ve used several rust converters over the years, and the Permatex 81773 Rust Treatment stands out for its simplicity and effectiveness. The 16 oz. bottle is a good size for multiple small projects, and the liquid goes on easily with a brush or spray. It’s thin enough to penetrate rough surfaces yet not so watery that it runs everywhere. On an old lawn tool and a couple of car parts, I applied it directly over rusty metal after brushing off loose flakes. The treatment dries to a black protective coating that seals the rust and leaves a paintable surface. It doesn’t just cover rust—it neutralizes it, which is key if you want your repair to last. Once cured, it’s much easier to topcoat with paint than sanding back to bare metal. The odor is noticeable but not overpowering, so I’d still suggest good ventilation if you’re using it indoors. Dry time is fairly quick; within a few hours I could handle the treated parts. The finish is a bit uneven if brushed on too thick, so thin coats work best. Bottom line: A reliable, easy-to-use rust converter that turns flaky surfaces into a solid base for painting or long-term protection. Great value for automotive, tools, or household metal projects.

This rust converter works as advertized. I had a 40 year old replacement hood that had been painted by the factory with lacquer and had not withstood the test of time after being parked outside in the weather & sun for 40 years. The hood was covered with surface rust so a very quick sanding followed by painting it with this created a primer & paint-ready finish. Just remember if you brush it on it WILL leave brush strokes you'll have to sand off or make sure there are no brush marks in applying it.

Great product. But mostly if you follow instructions closely. I'm ordering a new bottle for the mower decks on my tractors. I used this product three years ago to keep the 20-year-old replacement floor pans in my '89 F150 from rusting through. This has been a little miracle for me. Make sure you prepare the surface properly and use plenty of ventilation. I recently pulled the carpet and the pads of my truck to reapply, and the floors were still 90% rust free. I wire brushed them, removed any loose stuff on the surface and gave them a new spray making sure to hit all the hard to reach places. Make sure the cabin of your vehicle doesn't leak because wet carpets and pads are a sure fire way to rust out your floor pans.

Works great but make sure you prime and paint after 24 hours or it will start rusting again. It covers a lot of area and will last along time if you store it correctly.

Works well. With any rust repair you aren't gonna have perfection theres always something that is more damaged than you want ived used this for years and it will convert and well, i have always removed as much rust as i can first, then just paint it on. The dry black layer it leaves is your indication that it worked.

I have used this product for two decades if not more. I keep cars a long time. I used to live in the rust belt (Michigan). I would skin the vehicle with sheet metal, but first I would wire brush it and get the the perimeter of the hole close to good metal. Then I would pop rivet the new sheeting over the hole. I used matching color of Rustoleum and my neighbor would comment on what a good job it was. One of these restoration would last ten years.

I used this product on the advice of Catalina Direct's DVD on refinishing a C-22 sailboat keel. I removed all the rust that I could from the cast iron keel with a 4.1/2" Makita angle grinder down to bare metal. There were pitted areas that resembled tooth decay that could not be accessed, so those were left as-is. I painted one side of the keel with 81773 Rust Treatment and allowed it to dry. It turned the keel into a beautiful black color and I was excited about the results. However, the next day it seemed the surface was fragile. Attempts to "roughen" the surface in preparation for an epoxy barrier coat saw the product flaking off at the areas where it was applied over bare metal. At this point I was skeptical and decided to do a test (as I had many more layers of various epoxy and body filling products yet to be applied). I applied a 12"x12" square of West System 105/205 marine epoxy over a sample area and allowed it to cure. I then came back with various tools to try to remove the epoxy. I was absolutely amazed at the quality of the bond. I was able to scratch down to the bare metal with a screwdriver and mallet, but attempts to "lift" the epoxy off the metal were utter failures. I tried using paint scrapers and even a razor scraper. The epoxy itself would fail before the bond to the metal, and I am convinced that the product works as advertised. I don't pretend to be a chemist, but I believe the epoxy either penetrated the Permatex product or absorbed it into the epoxy. Many users have complained that it's not for automotive bodywork. I don't believe this is correct. The product is not suitable for direct exposure to the elements. It needs a primer of some sort over it before paint can be applied. My experience was with epoxy, and I would predict that an epoxy primer would suffice, but other types might work as well. Unfortunately, the Permatex website is near useless when looking for answers. I'd say to test a section and see what happens.

If you aren't familiar with this class of rust treatment products, this is a rust converter, not remover. It works by chemically reacting with the oxidized iron and producing a black paint-like surface. In the absence of rust, it just produces some staining. This product does not remove rust, so you need to prepare the surface by first removing loose rust. The product is water based. That means cleanup is fairly easy before it has dried. (I usually apply it with a foam brush, which I then rinse off after.) But this also means that if you apply too much product on horizontal surfaces, the pooled product can actually cause more rust. Additionally, the product directions do warn to let an item fully dry before top coating. And that you can't top coat with water-based paints, unless you use an oil-based primer. This Permatex 81773 version doesn't seem to behave any differently from other brands of rust converters that have the same milky tan appearance. The product page here claims this version is "Body Filler Compatible," but the bottle itself makes no mention of that. More importantly, it says, "NOT RECOMMENDED FOR AUTOMOTIVE EXTERIOR SHEET METAL REPAIRS." (No explanation for why this is the case.) Ummm...that kind of makes the body filler issue irrelevant, as automotive exterior sheet metal is the primary place where you use body filler. I thought maybe Amazon sent the wrong product, but I verified the item number matches.