Bests & Worsts Reviews from Amazon

I have tried a number of 'so called' rust converters in a variety of applications. The most difficult is when you have heavy farm equipment that is well rusted. The real problem is when you wire brush the steel with a heavy duty SS wire wheel using an angle grinder, you cannot get to the bottom of the rust pits. This is a big problem because if you don't get the rust out of those pits all the work is for naught because it will just rust through again in a year or two. So, my objective was to find some way to fix that problem. To start with I am a chemist so I understand the oxidation process and the difficulty of getting that under control. Simply put, you must intimately coat the entire surface of the metal with a good oxidation resistant primer. Intimately - meaning there can be NO rust...not even a little tiny bit or it will just rust through again. After using various rust removers I found that none will get down into those rust pits and completely remove heavy rust - NONE. Some worked fairly well on flat smooth metal but NONE would remove the heavy rust from the bottom of those rust pits. Many were 1/16" deep so even a wire wheel can't get into them. And, I'm not about to grind 1/16" of metal off of 1/4" plate steel. Next, I went to rust converters. There are a number of these on the market. One of those that was highly rated on the internet would work in some areas but not in others. In some cases it actually generated copious amounts of an orange-ish corrosion that was self replicating once I started it with that 'highly rated' rust converter. I was not impressed. The last thing I tried was the VHT rust converter. Frankly, I didn't have high hopes. However, this stuff did exactly what was claimed. Where there wasn't any rust it simply went on as a clear primer...and in those areas it bonded very well. Where there was heavy rust...especially in the bottom of those rust pits...the rust converted to a very hard black material (I believe it is iron sulphate)...in any event it is 'hard as nails' and actually much harder and, it prevents future rust from forming. This is amazing stuff and I recommend it highly. Note well, the can suggests more than one light coat to make sure you get everything covered. Because of the nature of the problem I was dealing with, I first put on a heavy coated to make sure the heavy rust in the bottom of those pits was completely saturated. Then I would sand the surface to make sure it was smooth and give it another light coat. Then, for added assurance, I used another primer available on Amazon called self-etching grey primer by Rustoleum. This is also a great product. I really like it's leveling and sanding properties. Since then I learned that VHT also has a self-etching primer, so I will try that soon. Finally, I finish with a couple coats of a good quality spray paint. I ran experiments repeatedly on all combinations of these and found that the VHT rust converter followed by the self-etching primer provides excellent rust protection and very good bonding. Be sure to follow the instructions because with these reactive materials you must apply the next coat within minutes to insure the layers react to one another. This maximizes the bond and prevents inclusion of any foreign material (including moisture) that could initiate rusting later on. From my experience, THIS is the best product on the market. Also see my comment on one star reviews under the question about how Rustoleum and VHT rust converters compare. PS Never try to do this kind of work on a foggy morning where moisture is condensing on surfaces...you will be wasting your time! UPDATE 9/6/2016: It's been almost two years since my initial experiments and I received a question from Sarah "How has this held up?" Very good question and a timely one as well...now, first a little background; I have a John Deere 950 with a 60" pull behind mower. The top of that mower deck where the leaves tend to set and hold moisture was badly rusted. However it was NOT pitted like the back blade. I sanded the mower deck down to bare metal, primed it and painted it using John Deere primer and paint. That job was done 2 1/2 years ago and I did NOT use any VHT rust converter. [See first two photos.] Rusted right through the new primer and paint. This mower is covered during winter months. Now the 'back blade''; this is where I used VHT rust converter. I decided to just try it out on one side of the top of the back blade. I've still done nothing to the other side. The third photo show the result of wire brushing, VHT primer, Rustoleum self-reacting primer and then the final John Deere green paint. Almost two years later it is flawless...no sign of rust. And remember, this equipment sits out in the elements all year round. Fourth picture is the other side which I've done nothing to...that is the way both sides looked before I started. Rather an impressive testimony to the combo of VHT rust inhibitor and Rustoleum self-reacting primer before painting!