Ok, I know I am going to catch some flack for posting this here, but I know I will get more feedback here then I will in the paint and body section, and since it is on a 73 ford pickup its not completely wrong. My question is simple, do rust converters work? Yesterday, I was working at blasting and priming a 73 cab. To you give you a little back ground, this particular body came out of hiding when I found it a couple of years ago. It was a 50,000 mile beauty that and elderly gentleman parked in a shed 15 years ago and forgot about. the cab corners and floor are in good shape, and I will need to do minimal repairs to the entire body. The problem I am having is simple, I am finding lots of surface rust pits as I strip it. No doubt from sitting in a damp shed for 15 years. none of the usual body rot, only a few holes to contend with. However, as I am blasting I am amazed at the pitting action. anywhere there was a rock chip, there is a pit. I dont feel like I am getting all of the rust out, I can still see a little black spec down in there deep if any of you body men know what I am talking about. I shot a coat of vinyl etch primer on the bare metal last night, and then layed in bed dreaming of rust bubbles coming through my beatiful paint job. Any thoughts? Does anybody have any hard and fast evidence that por 15, rust bullet, etc. works in a situation like this?<!-- / message --><!-- BEGIN TEMPLATE: ad_showthread_firstpost_sig --><!-- END TEMPLATE: ad_showthread_firstpost_sig --><!-- sig -->

 

Some years ago I had to work on a truck at work so I also touched up some of the frame rust. I used some Spray On aerosol rust converter and it worked awsome. Just brushed the rust to get the loose stuff off, sprayed it on and got a nice hard black surface when dry. Now I can't find the stuff anymore. I got some Duplicolor rust converter to try but it isn't near as good. I'm looking for something good also. I'm not shure how rust converter would work under a paint though. I always used it on surfaces that didn't get painted.

 

I remember permatex had a product like you are talking about. I messed around with it years ago, what I am wondering is, does anybody have any hard and fast evidence. Something like, yeah, I coated a piece of rusted tin and left it outside for 2 years and the rust didnt come back. LOL I need reassurance

 

rust requires two key ingredients air and moisture. eliminate them and no rust. so i would say a little spot of black down in a pit shouldn't be a problem unless air is allowed access to it again.

 

A friend of mine has used por-15 in the past.
It has worked really well for him, except for the last time he used it.
This last time, he prepared the surface by sandblasting and then cleaning it.
After that, the por-15 was applied. Once it cured, he was able to wipe it off with his hand.
The stuff, apparently, is formulated to be applied to rusty surfaces.

Food for thought.
Murph.

 

generally sand blasting should be the end all of rust, unless it was just a quickie spray, then you could have left rust in the pits, or you just have some stub burnt rust,

now if you want a chemical alternative to sand blasting, and a you want to make sure there is zero percent chance of any remaining rust from remaining, (this process is also great for removing rust from a number of objects from tools to car parts, to what ever)

well you will need to find your self some Phosphoric acid, its the active ingredient in rust converters/rust removers, even simple Coca Cola and Diet coke also works as well, but i have found that they both will remove rust, and at a very slow rate, go take a rust bolt and sit it in a cup of coke for a week or 2, it contains very little Phosphoric acid, for obvious reasons (its a human beverage)

http://en.wikipedia.org/wiki/Phosphoric_acid

best bet is to go to your local Home Depot or Lowe's or ??? not sure where you live? i am going to assume the U.S. so go to your local big box store like Home Depot and go to the paint area, and look for a concrete prep and etch, read the ingredients on the label, if it doesn't contain Phosphoric acid, you don't want it, it won't work,

other acids will remove rust, like muriatic acid, but they don't work as well as Phosphoric acid, and if you use Phosphoric acid, you don't run the risk of good metal being eaten, i don't suggest you leave a part in Phosphoric acid for 1 week or longer, but if you soak a part for a few hours you should notice some fast acting rust converting/rust removal

https://www.ford-trucks.com/forums/2...treatment.html

on my truck i used some concrete etch stuff, it says on the container that its a rust remover for concrete, i couldn't find Prep and Etch in Canada at our Home Depot, had to go to another store actually to find a product that contained Phosphoric acid

here is a before picture i found on the net of rust,
http://i248.photobucket.com/albums/g...t/IMG_3215.jpg

here is the after picture using the Prep and etch stuff from Home Depot,
http://i248.photobucket.com/albums/g...t/IMG_3230.jpg

http://i248.photobucket.com/albums/g...t/IMG_3223.jpg


http://i248.photobucket.com/albums/g...t/IMG_3224.jpg

here is the product, i couldn't find this in Canada, but from what i read Home Depot has it in the paint section, i did find a product that is basically the same thing, it worked really good, i did find that using a brush and kinda stabbing at it, so bubbles would appear was best, and before you brush it on, shake the container really good, it seemed to work even faster when i did that, it seems when its being mixed up or stirred up by a paint brush on the surface of the metal, and bubbles are formed, it works the best, when you pour the stuff on, the rust will actually fizz, its very neat,

the black stuff left behind is fine, its just converted rust, its been converted back to a neutral iron phosphate, you can take a steel brush to it, and remove it before you apply primer/paint,

now you can buy the little bottles of rust converter, and pay the same amount as you would pay for a big jug of the active ingredient chemical from Home Depot, i like to save money, and buy things in the largest quanity i can get for the cheapest amount, plus those little cans/bottles will get very expensive after you go through a few,

so let the chemical soak, but not dry, then every 15-20 mins reapply some more, and continue depending on how bad the rust is, for heavy rust, more coats are needed to penetrate,

then rinse and give the area a good wipe, then if you have a torch or heat gun, simply go over the area with some light heat to dry up the metal, thus getting all the water out of the pores,

basically this chemical process kinda works on the same Principal as Electrolytic Rust Removal, except large parts are generally hard to fit in water containers, that's where the chemical process is nice as you are not limited to part size, and generally any one can use the chemical, and you don't need as much prep or time to do the same work, now the chemical will involve more elbow grease, don't get me wrong, its not simply flicking a switch, but the electrolysis method is time consuming with setup, and takes a long amount of time, plus if your not careful, you can destroy the part you are trying to save, if you leave it on too long for example, and your limited to part size because of container size,

i hope all my info helps, if you click my youtube video link in my signature then you will get a idea on what i am involved with!

here is a video to explain the electrolysis method,

http://www.youtube.com/watch?v=R5I5WBG5HPw




-Brent

 

Ospho is a rust converter used by the US Navy. Who ever said a steel ship would not rust in a salt water enviorment? I bought a gallon of it for myself at a Dupont store I believe. A gallon will last forever.

 

Thanks for that guys, that is exactly the kind of advice I was looking for. I have always blasted to rid unwanted rust, but this one is a little menacing. I have messed around with the electrolysis process before, so I know what converted rust looks like. I think I will continue blasting, and then maybe just try the phosphoric acid for a little insurance policy. Any other opinions would be greatly appreciated.

 

It sounds like that phosphoric acid does a better job than the stuff I have which I got a few years back. It's labeled as a "polymeric rust converter" and uses tannic acid. It's used in the potato processing houses around here where the equipment is constantly exposed to a wet environment... It seems to be labeled under various different brand names but the one bottle I'm looking at now is called "Metal Medic"...

 

you can buy the rust converter in a spray can, but that stuff is expensive for the amount you get, like many other products like rust eater, rust killer etc etc,

so yeah the large amount you can buy at a good price at Home Depot, Loews, which is a concrete cleaner/etcher use's the active ingredient in the rust converter/killer/eater products which is Phosphoric acid,

its simple science, sometimes science can be interesting and helpful! who knew a chemical could eat rust? i just Google searched, what is the active ingredient in rust converter/killer/eater? then Phosphoric acid came up, so i did some reading, and went to a few links, and i was amazed,

you see i went to the local auto store, and was turned off by the high price compared to the small amount, thus i passed and tried to figure out how it worked, and what made it work, thus i got the more pure, cheaper version of a rust converter, and a better bang for your buck,

glad i could help, in the fight against rust, i try my best to help anyone i can!

"RUST NEVER SLEEPS!, BECAUSE OF PHOSPHORIC ACID!!!!"


-Brent

 

Its funny, cause I am friends with a fair amount of body shop guys, and at lunch time one of them walked into my office to borrow something....my board sander. LOL, anyways....I asked him what he thought, and he doesnt think rust converters actually work. I told him I was sandblasting and etching, apparently thats what he does. Either way I am going to try and use some phosphoric acid where I dont feel like I am getting all of the rust out of the pits.

 

he doesn't believe rust converters work? yet he uses a etching chemical? that contains Phosphoric acid? lol lol

ah well, i don't like using rust converters either, to expensive for the amount you get, i would rather use the pure active ingredient and get more bang for my buck,

just another idea,

from what i read, you can Google this, but i am thinking its also good for cleaning up chrome that has rust on it, and would be a good treatment for the inside of chrome bumpers, to stop any rust from eating through and popping up on the other side of the bumper, then a good coating of some undercoating on the inside of the bumper, would be a good treatment after the rust is neutralized/removed from the Phosphoric acid, also from what i read, Naval jelly uses Phosphoric acid, that's why it works so well, you can Google Naval jelly, they use it in the Navy on dealing with rust on ships,

-Brent