Of you who have used a rust removal or coverter product on a large surface (body, fenders, frame) what do you have to say about it?
The stuff from Ace Hardware that is non toxic called evapo-rust really works well... if you can soak the part. Otherwise, you will need to scrub and keep it moist all the time for it to work.
I've used naval jelly (which doesn't work very well) and I've used ospho (phosphoric acid) which does work well, if you let it soak the part as well... (but, the ospho stuff had a chemical reaction in my head and left the part with black gunk in it that I had to sand blast out (yuck)).
So, I would use the evapo-rust stuff... But, I don't know how "reusable" it is once you've used it?
I've tried Ospho 4-5 times on different parts and for some reason it never dried very well. I did this in the Summer when temperatures were warm and I wonder if our usual high humidity was the culprit? All of these parts were meticulously cleaned and only had the lightest of surface rust but the Ospho left the surface with a light gummy residue.....Michael Pawelek
So, so far the evapo-rust is the best product. I too have used the naval jelly and I was not impressed at all.
I know many here frown on Muriatic Acid, but I have been using it for rust removal on my Model T projects since 1970 and, in my opinion, nothing works better. I soak smaller parts in it or paint it on larger areas. It removes only the rust all the way down to the bottom of the pit, leaving the good metal untouched. After the rust has been removed down to the bare metal, I neutralize it with a solution of baking soda in water until it stops bubbling, rinse with clean water, dry with a towel and then quick dry the area or part with a heat gun to minimize the appearance of surface rust. The part or area is then ready for priming or painting.
I have become accustomed to the fumes whereby they hardly bother me at all, but if you find you can't tolerate them, work outdoors and set up a fan to blow the fumes away from you...or hold your breath. Also, the fumes can cause your other bare metal parts or tools to rust so keep it away from your toolbox and when not using the Muriatic Acid keep it in closed containers so the fumes cannot escape. Jim
Ortho Phosphoric acid , that black gunk that Micheal was mentioning, is in effect the rust that was left inside of the head in a converted state (neutralised), maybe best to have left it there, as new rust will form around that area that you sandblasted back out.
If you use this product ensure you have gloves ( surgical are the best for this) and use in a well ventilated area,
If you have had a freeze crack in the top of the block that you had fixed , this product works well to create a barrier over the top of the inside of this repair, kind of insulating it from a fast return.
This info to the best of my knowledge is correct BUT always ask the question prior to usage.....
The thing about Evapo-rust, beside excellent results is that it's non-toxic, non-caustic & is resuable for several times.
As some of you may know, I restore old gas pumps. On my gas pump forum Oldgas.com, a vendor posted his rust remover. Some people called it spam, and took offense to his post. I asked for, and received, some free samples. As I only received, a few four ounce bottles, my experience with it is VERY limited. With that said, my experiences with this product, have been excelent. It is as easy as they say, and it works as good as they say.
Here is a link.
Again, I want to stress, that my experiences are limited. I have only used it on small parts. I have not used it on large parts, or, in large quantities, because I haven't had the time to undertake a large project yet. But I do plan on using it again.
I have no connection with this product, nor do I receive any compensation for my reccomendations.
I've used Blue Lightning rust remover on items small enough to submerge in a gallon of the stuff. It removes rust very well, but not paint. You can google it to find the website.
Well. I hate to disagree David, but the black gunk was so massive that it clogged the head completely. so, leaving it in was not an option. I would hope that the antifreeze stuff or the water wetter stuff is made so that most of the rust would not form again, but I could be wrong... I just don't think that if you are going to use it on internal cooling parts, that require hot water moving through it, or on large body parts, that require being clean from debris/rust to be painted, that you would want this black residue left behind to interfere with a nice paint job or a good cooling system. Now on other things it may be a good idea such as Nuts/bolts/brackets/etc.. that need cleaned up.
but, evapo-rust sure is hard to beat and you can leave your hands in it if you have to... it seems to me that it is a citrus product???? not sure but it leaves a sticky residue on your hands that easily washes off in water.
Sorry Micheal , l should have said when it is dried to the surface, as you mention yours was a significant amount more that l thought, yes this was the correct thing to do, but leaving the Ortho Phosphoric Acid to dry ( rolling the head or block to ensure a good overall internal coverage) will give you an extremely good barrier, just not for big gluggy stuff and again if you choose to use it, it will burn your skin if prolonged usage without a set of impervious gloves.
Maybe the product we( Micheal and David ) are talking about are similar but O P Acid will dry , but leave a hard black coating not a gummy surface as Micheal has describing with ospho, maybe they are different items, good luck anyway.
I once accepted an acid treatment product's claim that application would leave behind a surface that "paint tightly adheres to". While, I still find it indespensible for chasing into the pits of sandblasted items to keep them from quickly breaking out again with an oxide coating and for giving them an extended shelf life before recoating, I've also learned that eventual paint is easily chipped from those treated surfaces--even though I had carefully wiped or wire brushed them clean of excess product. I now lightly reblast before use and I doubt many would disagree if I stated that nothing grabs and holds paint better than a freshly blasted surface.
Jim and others, If your senses register the odor of any acid you're working with, it's working on your esophagus and lung tissue--cumulative damage that likely will catch up to your indifference, before you reach the end. Organic vapor cartridges available for better quality masks will provide adequate protection. A lifetime member of the Careless Club, when the smoke hung low over CA last summer, and my neighbors all were able to tough it out, I was forced to gasp and cough my way to residency in another state for weeks at a time. Be kind to yourselves!