View Full Version : Rust Removing using Phosphoric Acid
Rods56
11-23-2010, 09:55 AM
Hi all...
Ran across this on another forum and I thought I would give it a try...boy, does it work!
I ordered a gallon of MILKSTONE PHOSPHORIC ACID from Tractor Supply for $12.00. Fnally got it in and I dipped a small heavily rusted part in to it full strength....last night around 8:30 PM and checked it this morning around 5:00 AM...it looked 'brand new'
I am going to take some photos of before/after to post so that you may see the results...they use this stuff in dairy's to clean milking machines! Someone told me that it will dissolve concrete too! (He used it to clean concrete mixer trucks)
In metal work...rust is going to happen...this stuff does a great job...just use common sense and use self-protective gloves, face shield, apron...and you should be fine. ;)
:?Rods56:?
whateg01
11-23-2010, 11:01 AM
I've used diluted HCl (watered down muriatic) for rust removal. The thing I was always cautioned about was that even after neutralizing it, it would continue to dissolve the metal. I've never heard that about phosphoric acid, but always wondered. Phosphoric should be safer though. What did you use to neutralize it afterward? Or did you just rinse well?
Sure easier than trying to coat small parts with naval jelly.
Dave
jlrussell4
11-23-2010, 02:00 PM
I tried white vinegar. It works great and it's inexpensive.
oldgoaly
11-23-2010, 02:49 PM
I've used phosphoric, still use it. The problem I have had is I forget how long it has been in there. now using molasses, rinse with water, then slosh in the phosphoric tank (55gal barrel) Savogran "Crete-nu" is the stuff I have been using diluted in water. The deer in the area "know" there is molasses in the shop! tt
Dawai
11-23-2010, 07:57 PM
Don't forget the safties.. I used some eastwood Phosphor.. got a bright red burn on my arm and I was not even aware I had gotten against the hood I was working on.. down the hinge seam...
sometimes... that is the best way to change rust to something else to coat over it. (don't it change it to a phosphate)?
Most the rust has came back in places on the 41 chevy I derusted in Soda and electrical current.. that is the crappy primer I used thou not sealing it.. I think.. the other parts I went ahead and painted are fine. Or ya just can't see it yet..
Peter Miles
11-23-2010, 09:41 PM
Hi all...
Ran across this on another forum and I thought I would give it a try...boy, does it work!
I ordered a gallon of MILKSTONE PHOSPHORIC ACID from Tractor Supply for $12.00. Fnally got it in and I dipped a small heavily rusted part in to it full strength....last night around 8:30 PM and checked it this morning around 5:00 AM...it looked 'brand new'
I am going to take some photos of before/after to post so that you may see the results...they use this stuff in dairy's to clean milking machines! Someone told me that it will dissolve concrete too! (He used it to clean concrete mixer trucks)
In metal work...rust is going to happen...this stuff does a great job...just use common sense and use self-protective gloves, face shield, apron...and you should be fine. ;)
:?Rods56:?
Keep in mind that the dairy equipment that is being cleaned with that stuff is either stainless steel or glass (transparent lines so that you can see the milk running through them.
shortbus
11-24-2010, 08:17 AM
Isn't that basically what "OSPHO" is? It's also the main ingredient of "parkerizing" used in the military.
http://preventrust.info/ospho-rust-primer/
cary
oldgoaly
11-24-2010, 01:24 PM
Rod,
looking at your pics it seems pretty quick acting, if you have a barrel handy, rinse your parts of into it, then you could used the diluted solution for things your not in a hurry for. Does it seem temperature sensitive? my molasses has slowed down since it has cooled off here. Before you think we have a pic problem, here is a link to Rod's pics http://www.metalmeet.com/forum/album.php?albumid=253 tt
Roger J.
11-24-2010, 01:37 PM
I'm certainly no pro at this stuff,, but I've been using Picklex 20 for a few years now. It won't remove heavy rust on a panel, but for light surface rust it works really well. Best of all, there's no need to rinse the surface with water afterward. Just spray it on (lightly), hit it with a red rag, let it set for a few seconds, and wipe it off.
It's no miracle worker though. In high humidity, you will most likely get some surface rust forming after a while.
pokerporouski
02-02-2011, 04:39 PM
Hey everyone, this is my first post but to through my 2 cents worth in. I have used muratic acid to clean motorcycle gas tanks for years but you have to run water in them for a while to make sure it stops eating after the rust is gone. The kits you buy to kreme a tank is muratic acid with white viniger to delute but it is cheaper to get it form lowe's or home depot than in the kreme kit.
Rasper
02-03-2011, 04:39 PM
I use muriatic acid and then an overnight soda bath. The thing I watch out for is to not use it on anything with cracks or crevices. The acid can hide in those places and cause problems later.
Richard
hogdaddy
06-09-2013, 09:40 PM
Resurecting an old thread here.
Evapo-Rust from your local Autozone works well for rust.
I have used muriatic acid and neutralized it with baking soda but watch those fumes.
I have used phosphorate acid from auto paint stores and it works well but somewhat expensive.
Hey this is my first post! :)
custommetal
06-10-2013, 06:22 AM
Just a quick comment on the phosphoric acid and muriatic acid uses. I learned to keep the containers with the acid in them sealed in plastic bags and away from anything metal. Seems the fumes will creep out from a screw cap and rust anything nearby. Baking soda is a cheap neutralizer. If you need a lot can get it at a pool supply store.
vBulletin® v3.8.6, Copyright ©2000-2013, Jelsoft Enterprises Ltd.