Phosphoric Acid - Where Have You Been?!

[TexasBoss]

Read a "how to" on rust treatment on another site and it recommended using a metal prep (phosphoric acid) on rusted parts. You can buy this at Home Depot for $17.99.

I bought this product (and rubber gloves) and dumped the entire gallon undiluted into a five gallon pail. I lightly brushed the surface with a wire brush, dumped the parts into the bucket and walked away. Came back in 30 minutes and OMG, the parts looked like they had been media blasted! I had a second pail with water and baking soda to neutralize the acid. I rinsed the acid bathed parts in the second pail and dryed. Below are a few before and after. 

I'm going to try this process on rusty brake parts and nuts and bolts. Wish I had known about this magic juice years ago!

P.S. I used Self Etching primer on the post acid bath parts. The acid will strip to bare metal and the parts will flash rust fairly quickly (couple of hours).

 

[Kilgon]

Looks good. Would be nice to see the parts right after the acid bath. Might want to get some "after blast' from Eastwood. It keeps metal from flash rusting after stripping. Works great. Gives you time to get a lot of parts ready for painting at one time.

 

[machattack]

Read a "how to" on rust treatment on another site and it recommended using a metal prep (phosphoric acid) on rusted parts. You can buy this at Home Depot for $17.99.

I bought this product (and rubber gloves) and dumped the entire gallon undiluted into a five gallon pail. I lightly brushed the surface with a wire brush, dumped the parts into the bucket and walked away. Came back in 30 minutes and OMG, the parts looked like they had been media blasted! I had a second pail with water and baking soda to neutralize the acid. I rinsed the acid bathed parts in the second pail and dryed. Below are a few before and after. 

I'm going to try this process on rusty brake parts and nuts and bolts. Wish I had known about this magic juice years ago!

P.S. I used Self Etching primer on the post acid bath parts. The acid will strip to bare metal and the parts will flash rust fairly quickly (couple of hours).

 

[machattack]

Your absolutely correct!!

I started out mixing my own from acid then found this a year and half ago. I also use it straight. I about wet my pants in happiness when I used it the first time.

Texas boss.........Thank you for sharing your discovery with others. You helped a lot of folks with this gesture.

 

[keiths71]

I love that stuff, my wife calls it mr. derusto, I've been using it for years and found out one thing the hard way. I would routinely soak hardware in a cup over night. I put a batch in a cup forgot about it and went to Miami for 4 days. When I returned it was like a big green kool aid popsicle. It took hours to break it up and clean up the stuff I needed. Another good product is RBL Products restoration plus wipes or sponges. If you have bare metal sitting around, even a whole body it will keep it from rusting a good amount of time, here in florida it works well. Go to RBLProducts.com

They have a lot of cool stuff.

 

[Fabrice]

@kilgon

I use the same acid over and over weekly. What I love about it is the respect of the surface vs sandblasting.

[Would be nice to see the parts right after the acid bath]

Depends on the metal/alloy and the way the surface was treated. For most of our parts, you end up with iron phosphate layer.

A dark grey/blackish deposit (sometimes an iridescent result if you ph balance while still wet) . If you want see how that looks, I have posted many images of the parts state right after a bath or brushing, from fenders, driveshaft down to bolts&nuts.

I buy it concentrated 75% in quart with no additives, which is very handy as you can brush/apply more concentrated and gradually dilute with water as you go. Ideal for large parts such as fenders, as they usually do not fit your container For these, I let them above my container while I dilute, every drup is then collected and can be reused over and over. Bought 2 quarts, still have 1/3 of one in bottle. bath is reused weekly. It doesn't loose its magic over time, but I do see that temperature plays a big role in process. Now with cold weather, I count in hours for the same job that would take minutes during a warm summer day.

Can't really think about a more effective and cost saving way to remove rust. I know I want nothing else.

 

[TexasBoss]

Agree about the temp and performance. The container says best if used above 65 degrees. Fortunately living in South Texas means I could conceivably use it on Christmas Day. I agree with reuse. I strained my leftovers through a paint strainer and it appears just as strong in repeated applications.

 

[Kilgon]

@kilgon

I use the same acid over and over weekly. What I love about it is the respect of the surface vs sandblasting.

[Would be nice to see the parts right after the acid bath]

Depends on the metal/alloy and the way the surface was treated. For most of our parts, you end up with iron phosphate layer.

A dark grey/blackish deposit (sometimes an iridescent result if you ph balance while still wet) . If you want see how that looks, I have posted many images of the parts state right after a bath or brushing, from fenders, driveshaft down to bolts&nuts.

I buy it concentrated 75% in quart with no additives, which is very handy as you can brush/apply more concentrated and gradually dilute with water as you go. Ideal for large parts such as fenders, as they usually do not fit your container For these, I let them above my container while I dilute, every drup is then collected and can be reused over and over. Bought 2 quarts, still have 1/3 of one in bottle. bath is reused weekly. It doesn't loose its magic over time, but I do see that temperature plays a big role in process. Now with cold weather, I count in hours for the same job that would take minutes during a warm summer day.

Can't really think about a more effective and cost saving way to remove rust. I know I want nothing else.

Sounds great and from your build post I know what you are replying to as for the strip finish.   Would of been nice to have know about this stuff about 2 years ago!  Of course,  if I would have and should have searched this site I'm for sure I would have found a previous post on it.  :whistling:   Now I'm going to have to let something get rusty so I can go buy some and use it.   rofl

 

[Mister 4x4]

"Where has it been?"

Sorry - my fault.  I used it all on mine.  Looks like the market is finally beginning to recover.

lollerz

 

[Hemikiller]

To prevent, or at least ******, flash rust, use a product with a zinc component, which forms a zinc phosphate finish on the dipped parts. It's not a long term solution, but also eliminates the need to any sort of etching primer. Two products that have the zinc are Metal Blast from Rust Bullet

https://www.amazon.com/Rust-Bullet-Treatment-Remover-Plastic/dp/B001BPY8FG/ref=sxts_sxwds-bia?gclid=CjwKCAiAob3vBRAUEiwAIbs5ThFsqWuBWNsjCH-bpMtPq8udIV8jcw06dEhuLickm4kVV_6hrss6YBoC9UUQAvD_BwE&hvadid=176359691167&hvdev=c&hvlocphy=1014739&hvnetw=g&hvpos=1t1&hvqmt=e&hvrand=13028671546608631478&hvtargid=kwd-16244178032&hydadcr=25271_9775796&keywords=rust+bullet+metal+blast&pd_rd_i=B001BPY8FG&pd_rd_r=3579bda1-29c9-4f59-9481-29ef29ff4ef2&pd_rd_w=qrdLU&pd_rd_wg=F0yUl&pf_rd_p=1cb3f32a-ccfd-479b-8a13-b22f56c942c6&pf_rd_r=DKNNTNKK49NATMNPJDH3&psc=1&qid=1575999386

... and Metal Prep from POR15

https://www.amazon.com/POR-15-40201-Metal-Prep-gal/dp/B00J594B52/ref=sr_1_1_sspa?keywords=metal%2Bprep%2Bpor15&qid=1575999419&s=industrial&sr=1-1-spons&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUExMDJRVE02Nk42UDZEJmVuY3J5cHRlZElkPUEwMDI5OTA2SjdBMzdMSTk1RVJSJmVuY3J5cHRlZEFkSWQ9QTA1NDU2NDkyTEJSNExNM0VBSkMxJndpZGdldE5hbWU9c3BfYXRmJmFjdGlvbj1jbGlja1JlZGlyZWN0JmRvTm90TG9nQ2xpY2s9dHJ1ZQ&th=1

I find that the Rust Bullet product outperforms the POR-15 by a fair margin. It works like POR-15 used to.

 

[TommyK]

Just be sure to look at compatibility with primer and topcoats when using phosphorous based rest remover/preventer products.

 

[keiths71]

I agree, On body panels I use it, wipe it down with damp rags, let dry then sand it thoroughly with 180,then clean it and follow up with a hinkle wipe or axalta ps 4000 wipe, I like Axalta 2580cr zinc chromate epoxy. not an inexpensive product but worth the peice of mind. I wouldn't worry about primering over the Kleen strip on other things like misc parts, trailer hitch etc.

 

[Carolina_Mountain_Mustangs]

I have used on rusted engine block that I could not get the pistons out. Let it set and knocked the piston out next day. Do be safe when using and wear goggles to keep out of eyes. That is also one of the acids in molasses that makes it work just lots slower.

I see you cleaned the hood latch and parking brake. You should get the Iron phosphate chemicals and treat them like Ford did. They used that on any parts that they did not want to stick because of paint. Hood hinges, upper shock caps, gas pedal, emergency brake, hood latch. Yes you can paint but there was a reason Ford did not paint them. 

When we made beer kegs they go through an acid bath to remove any traces of iron from the tooling process and clean the surface of the steel. We had people on that line that had nose bleeds all the time the fumes ate up the inside of their nose. Some of the customers also required a citrus wash after the acid to remove any traces of the acid with another acid, lol. Another reason we got out of the business too many medical issues. If you have kids be sure to lock it up just in case. Keep you something to eye wash right there also.

 

[NOT A T5]

I have used on rusted engine block that I could not get the pistons out. Let it set and knocked the piston out next day. Do be safe when using and wear goggles to keep out of eyes. That is also one of the acids in molasses that makes it work just lots slower.

I see you cleaned the hood latch and parking brake. You should get the Iron phosphate chemicals and treat them like Ford did. They used that on any parts that they did not want to stick because of paint. Hood hinges, upper shock caps, gas pedal, emergency brake, hood latch. Yes you can paint but there was a reason Ford did not paint them. 

When we made beer kegs they go through an acid bath to remove any traces of iron from the tooling process and clean the surface of the steel. We had people on that line that had nose bleeds all the time the fumes ate up the inside of their nose. Some of the customers also required a citrus wash after the acid to remove any traces of the acid with another acid, lol. Another reason we got out of the business too many medical issues. If you have kids be sure to lock it up just in case. Keep you something to eye wash right there also.

Excuse me? Neutralizing an acid with another acid? To neutralize an acid you need to use a caustic like NaOH (Sodium Hydroxide) or KOH (Potassium Hydroxide) etc !

Perhaps they went out of business because for not wearing proper PPE!!!

 

[92GTS-R]

After +reading this thread I have just purchased (what I think is the same product) in the UK



If I brush this onto the front floor pan aeras of the car, what do I have to use to neutralise the Acid once it turns the area grey?

There is the mention of water and baking soda?  What is the correct mix? 

Being in the UK  American known Products are not available.

 

[Don C]

A product I use, that is a 20% solution, says to wipe or rinse with water.

https://www.rustoleum.com/~/media/DigitalEncyclopedia/Documents/RustoleumUSA/TDS/English/CBG/Krud%20Kutter/KRK-02_The_Must_for_Rust_TDS.ashx

 

[Jeff73Mach1]

Good stuff. If your parts are dirty, degrease and pressure wash first and it will both work faster, better and your acid will last longer. protest your eyes and skin, but diluted, it isn't that bad if you get a bit on the skin.

For larger parts, you can put them in a kiddy pool and use a cheap pump to circulate it over the part.

 

[Carolina_Mountain_Mustangs]

I have used on rusted engine block that I could not get the pistons out. Let it set and knocked the piston out next day. Do be safe when using and wear goggles to keep out of eyes. That is also one of the acids in molasses that makes it work just lots slower.

I see you cleaned the hood latch and parking brake. You should get the Iron phosphate chemicals and treat them like Ford did. They used that on any parts that they did not want to stick because of paint. Hood hinges, upper shock caps, gas pedal, emergency brake, hood latch. Yes you can paint but there was a reason Ford did not paint them. 

When we made beer kegs they go through an acid bath to remove any traces of iron from the tooling process and clean the surface of the steel. We had people on that line that had nose bleeds all the time the fumes ate up the inside of their nose. Some of the customers also required a citrus wash after the acid to remove any traces of the acid with another acid, lol. Another reason we got out of the business too many medical issues. If you have kids be sure to lock it up just in case. Keep you something to eye wash right there also.

Excuse me? Neutralizing an acid with another acid? To neutralize an acid you need to use a caustic like NaOH (Sodium Hydroxide) or KOH (Potassium Hydroxide) etc !

Perhaps they went out of business because for not wearing proper PPE!!!

Never said that. I said after the Acid bath, that is required by government regulations for a food container, it went to citirs wash. The acid wash included many washes after the acid dip and were dried then went to the citrus wash. I think that was Budweiser that wanted that citrus.

We did not go out of business the owners got an offer they could not refuse and made millions on the deal . They had to agree not to open another business to compete or we would have put them out of business. Frankie is who bought it they make lots of sinks but soon found out kegs were not sinks. The business was Spartanburg Stainless Products, Inc. which before that was Firestone probably make kegs for 50 years. We had to send one of the engineers to help them get going they were totally lost.

BTW there was no breathing PPE required on the wash line, safety glasses, rubber gloves, shield, aprons & ear plugs. OSHA did not require respirators just huge vent s sucking all the steam out. Would eat the roof off and corrode the radio towers out back. Hey the government writes the rules they are not so smart sometimes.