Alternate Rust Removal Techniques

[motorheadmike]

Because the Monte has developed some surface rust I started investigating alternate means of removing rust. I am talking about not using a mechanical means (grinder or wire wheel or the like ) as I hate the mess it makes. Basically this means chemical in one form or another.

Vinegar, Citric Acid, Muriatic Acid, and Aluminum Foil (here is how that works https://www.reddit.com/r/LifeProTip..._get_rid_of_rust_by_rubbing_it_with_aluminum/).

1. A straight vinegar soak for 2 hours did nothing - 24hrs might yield a result;
2. Didn't even try Citric Acid might make a good paste for a vertical surface (could mix it with flour);
3. Muriatic by itself works well after just a few minutes when applied and gently agitated with a toothbrush ( but doesn't penetrate well - a wire brush can be used to break up scale);
4. Aluminum foil with vinegar took a massive amount of elbow grease to cut through to a level surface (it didn't so much as leave a noticeable scratch, the scratches shown were from the previous owner hand sanding off the original paint);
5. Muratic acid, followed by aluminum foil and vinegar (cuts down to the next layer), and more muriatic acid seems to do the trick (very smooth and level);
6. Is just muriatic acid, and vinegar/foil rubbed over the roof, you can see that the paint is still there. (same degree of material removal occurred);
7. The tools I used.

I am going to strip portions of the car with paint stripper, then treat with muriatic acid, vinegar and foil, muriatic acid again, and finally some POR-15 Metal Prep (to create a zinc phosphate coating), then primer, minor bodywork, and paint.

Should be interesting.

NOTE: I strongly recommend that if you are going to use muriatic acid that you use as little as possible, meaning put just a few mL into a suitable container and don't get any more until you need it. A little goes a long way and work slowly. This will reduced the risks to your person (noxious fumes and physical damage), and makes clean up/control easier in the event of a spill. Also keep a neutralizing agent handy - I have baking soda within arms reach. PPE is huge too - use a respirator (in a well ventilated area), gloves, and eye protection.

If you are in a rush - just get out the grinder.

 

[MrSony]

#8 C4

 

[Wraith]

If it's not too deep try Ospho and a wire brush, if it's deep use multiple applications. It's worked well for minor pitting on my project, I trust it more than the Por15 products.

 

[ed1948]

I've used sandpaper, wire wheels and rust converter, (like Naval Jelly), products to attack surface rust on the 95 GTI I restored 10 years ago. After 9 years only one tiny spot formed a rust bubble. I used POR 15 on the chassis seam surface rust where it also was successful in beating back the nasty rust. My opinion is that any good product will work well as long as the prep work is done thoroughly.
The way I understand the rust treatment process is to aggressively remove the surface layer of rust and then chemically treat it repeatedly and then cover it with good primer and topcoat. Ideally the metal should be 100% rust free (no rusty pits) and then immediately coated with paint. That will thin the metal somewhat which I don't prefer. That is why I depend on chemicals to neutralize the oxidation and good topcoats to seal.

I also use brass brushes to derust surfaces.

 

[motorheadmike]

Added a few more details/thoughts to the original post - after having had a chance to sleep on it.

 

[axisg]

for anything that will fit in a plastic barrel ( or in my case the biggest rubbermaid tub I could find ) I like to use electrolysis. Works great for brackets, air cleaners, again anything you can hang in the solution without touching the sides or bottom in a water-tight non-metal bin. I've been using the same solution for 2-3 years now. I also use PH Boost ( Hot Tub / Pool Chemical ) as I had it on the shelf. Its also great because the unit is submersed getting to the impossible to reach areas.


http://www.instructables.com/id/Electrolytic-Rust-Removal-aka-Magic/
+ tons of vids on youtube

 

[Crd80BU]

Because the Monte has developed some surface rust I started investigating alternate means of removing rust. I am talking about not using a mechanical means (grinder or wire wheel or the like ) as I hate the mess it makes. Basically this means chemical in one form or another.

Vinegar, Citric Acid, Muriatic Acid, and Aluminum Foil (here is how that works https://www.reddit.com/r/LifeProTip..._get_rid_of_rust_by_rubbing_it_with_aluminum/).

1. A straight vinegar soak for 2 hours did nothing - 24hrs might yield a result;
2. Didn't even try Citric Acid might make a good paste for a vertical surface (could mix it with flour);
3. Muriatic by itself works well after just a few minutes when applied and gently agitated with a toothbrush ( but doesn't penetrate well - a wire brush can be used to break up scale);
4. Aluminum foil with vinegar took a massive amount of elbow grease to cut through to a level surface (it didn't so much as leave a noticeable scratch, the scratches shown were from the previous owner hand sanding off the original paint);
5. Muratic acid, followed by aluminum foil and vinegar (cuts down to the next layer), and more muriatic acid seems to do the trick (very smooth and level);
6. Is just muriatic acid, and vinegar/foil rubbed over the roof, you can see that the paint is still there. (same degree of material removal occurred);
7. The tools I used.

I am going to strip portions of the car with paint stripper, then treat with muriatic acid, vinegar and foil, muriatic acid again, and finally some POR-15 Metal Prep (to create a zinc phosphate coating), then primer, minor bodywork, and paint.

Should be interesting.

NOTE: I strongly recommend that if you are going to use muriatic acid that you use as little as possible, meaning put just a few mL into a suitable container and don't get any more until you need it. A little goes a long way and work slowly. This will reduced the risks to your person (noxious fumes and physical damage), and makes clean up/control easier in the event of a spill. Also keep a neutralizing agent handy - I have baking soda within arms reach. PPE is huge too - use a respirator (in a well ventilated area), gloves, and eye protection.

If you are in a rush - just get out the grinder.

I used Phosphoric Acid got it at the farm supply store

 

[V8 Rumble]

I used evaporust and the rustoleum rust disolver worth great results when I did the frame off on my malibu. These plus your methods save a lot of money and time trying to locate parts.

 

[motorheadmike]

I used evaporust and the rustoleum rust disolver worth great results when I did the frame off on my malibu. These plus your methods save a lot of money and time trying to locate parts.

Tried those too and like them for smaller stuff. The problem is like straight vinegar they need the parts to soak (and become progressively weaker with time/use - thus the requirement for the bath). On a horizontal surfaces of large panels there is just no way to soak them (short of going to a commercial building and having them hot tank the car).

The other benefits of chemical stripping vs. mechanical stripping is the amount of heat introduced into the parts and the amount of material removed. You can go too far too quickly with a machine.

 

[Wraith]

There are much better options than vinegar, it's an acid by nature but an organic one at that. Phosphoric or muratic would be a better option, most acids aren't a pure/one acid only, the majority are a combo along with a wetting agent/surfactant to assist. Naval jelly is a good option without getting creative and mixing your own which I do quite a bit.