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The Ospho Solution..(rust removal)

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#1 ·
This is the start of a thread dedicated to successful rust removal using ospho,a water based phosphric acid product I've been using professionally for many years.
Ospho has some advantages over other methods, mainly a DIY can do it at home inexpensively with little mess,fairly easily.
I'll try to answer any questions and offer some advice on the successful use of this product.
.....First,I'll start with the most common use : To remove surface rust That has accumulated on unprotected steel....Then heavly rusted and pitted metal,and using it to prevent surface rust of freshly stripped steel...
...
The pics below show the trunk floor and wheel wells I made for my old car.After making the pieces and screwing them together ,it got cold out and I put the car up for a couple months and the steel got pretty rusty.
In the interest of time I'll just do a spot to show how its done and what Materials you'll need.Bare with me I'm a newbie with the computer.
 

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#187 ·
That is what I am thinking too, get it all out. I just picked up some Black Diamond media material and I am very happy with it's performance. I will see if I can come up with some Starblast and give it a try too.

Brian
 
#188 ·
Shine, what is the brand name of the Starblast? When I google it I get a few different ones, Clemtex, Marco, and Dupont, and that is just a quick google so I guess it's a pretty popular name. The Marco is $80 for a 50lb pail.:pain: double :pain::pain: The Black diamond I picked up was only $7.88 so that is quite a shock.

Brian
 
#195 ·
I agree with that...you have to remember how easy it is to screw something up especially for someone with little experiance. thats the whole reason for this thread,to help ospho users get good quality work.
I completely understand how someone (even a seasond pro )could use this one time,screw it up and hate the product ,all the time it was user error and has nothing to do with the product at all....Heres a good example I epoxied some fenders and didnt use ospho and the primer pulled off with the tape...I didnt blame the primer I looked more closely at what '"I" did wrong and found out first hand you cant spray epoxy when its 50 degrees out.Now if I was some old hard headed fossil I would have simply said that brand of epoxy SUCKS and thats it...
Ive seen old lacquer primer guys screw up epoxy and refuse to ever use it again and they are still using lacquer,it makes me cringe...
Ive mixed epoxy up at 4:1 when it was supposed to be mixed at 1:1 also ...mistakes happen..
 
#197 ·
What is so different with the Ospho?

Here is from their tech sheet. Nothing about removing or neutralizing!

RUSTED METALS - OSPHO is a rust-inhibiting coating - NOT A PAINT You do not have to remove tight rust. Merely remove loose paint and rust scale, dirt, oil, grease and other accumulations with a wire brush - apply a coat of OSPHO as it comes in the container - let dry overnight, then apply whatever paint system you desire. When applied to rusted surfaces, OSPHO causes iron oxide (rust) to chemically change to iron phosphate - an inert, hard substance that turns the metal black. Where rust is exceedingly heavy, two coats of OSPHO may be necessary to thoroughly penetrate and blacken the surface to be painted. A dry, powdery, grayish-white surface usually develops; this is normal - brush off any loose powder before paint application.

And from PPG's two versions.

DX579: Metal Cleaner
DX579 is a multi-purpose phosphoric acid based
cleaner and prepaint conditioner for most metals.
It can be used to deep clean a metal surface prior
to paint or to prepare a surface for a subsequent
chemical coating. DX579 is blue in color and
could lighten over time.


Apply Metal Cleaner (DX579) mixed 1:2 with water.
Allow to react 2–3 minutes, then rinse. Water should
sheet over entire surface. For Galvanized or Galvaneal,
use abrasive pad while applying.


DX520: Metal Conditioner
DX520 is a phosphoric acid based coating chemical
that will produce a zinc phosphate coating on
galvanized or steel surfaces. DX520 contains a
small amount of detergent which aids in the
removal of light soils and oils and promotes the
formation of a uniform zinc phosphate coating.
DX520 is pale green in color and may turn darker
over time.


Apply Metal Conditioner (DX520) straight from the
container. Allow to react 1–2 minutes, then rinse
well and dry. For Galvanized or Galvaneal use an
abrasive pad. Prime with DPLF Epoxy Primer in the
same day


What's funny is it doesn't say what to rinse with!

Brian
 
#198 ·
ospho, metal prep , naval jelly , milkstone they're all the same thing. a wetting solution containing approx 5% phosphoric acid . they have been around for ever. apply and let set but keep wet then rinse with water . when using alkyd base paints it is no big deal but no one has used that on cars for 40 years. but with epoxies and urethanes the acid has to go. each mfg will state in their tech sheets to rinse thoroughly with water. same goes for chemstrip or soda .
to anyone reading these threads , a simple call to your paint mfg will answer the question . every one i know of will insist you neutralize the acid or chemstrip / soda before applying their product . if you dont you can forget any help or warranty .
 
#199 ·
Very true, I plan on using some ospho but will be removing it. But I am also going to be doing some tests using it exactly as they describe and see how that goes too. Just for the fun of it. :D


Brian
 
#204 ·
some additional tips

Hi Barry Am I the so-called expert who you asked about? I hope not.As far as rust removal, couple of tricks if you have a rusty hood or fender soak a absorbent rag and drape it over the rusted area. If it's wet its working. Sometimes rust won't budge it looks like solid surface rust but the acid won't touch it. It's got paint under it. Spray paint remover watch the paint surface scrape and remove paint. Apply the Ospho, Rust Cure, or my personal favorite Mastercoat Rust Remover and prep and the rust will dissolve. Denatured alcohol can be used to neutralize these products when a water rinse would result in flash rust.
 
#205 ·
Hi Barry Am I the so-called expert who you asked about? I hope not.As far as rust removal, couple of tricks if you have a rusty hood or fender soak a absorbent rag and drape it over the rusted area. If it's wet its working. Sometimes rust won't budge it looks like solid surface rust but the acid won't touch it. It's got paint under it. Spray paint remover watch the paint surface scrape and remove paint. Apply the Ospho, Rust Cure, or my personal favorite Mastercoat Rust Remover and prep and the rust will dissolve. Denatured alcohol can be used to neutralize these products when a water rinse would result in flash rust.
Pay no attention to me, all the lies and BS I have seen you post in the last month, tells me you have no clue about paint at all.

NOTHING I say will ever have anything to do with you.
If igornance is bless you must be estactic.
Have a good day.
 
#206 ·
Barry your real class act, now you call me a liar after all the BS that you ran with your trolls. Quick review, doesn't adhere well under 65°, salt spray testing B117 435 hours and blistering occurred ,not too impressive I hope you were joking about flash rust being the painters best friend.I'll put my Mastercoat primer against yours any day the week. As far as rust work your epoxy is not the answer. Since when is a production paint job so desirable on a build. Paint jobs that we do on cars go 20 years ,not your average 7 to 10 year production job.. Vintage car sof Fort Mill South Carolina learned that years ago. So run your mouth all you like as far as I'm concerned I would not use your product and I wouldn't deal with you as a persons. So rant all you like Sorry I won't be here listen to your crap I have a busy day planned kma:evil::spank:
 
#213 ·
#214 ·
#215 ·
It took me a while to find it available in single quarts or gallons. In site after site and the one place I found locally who could get it, it was by the case, 12 quarts (at $25 each locally) and four gallons, that is the only way I could get it until I found it on Amazon.
Brian
 
#218 ·
So I got my first use of the ospho today. On the nice clean bare metal it looks great, on the rust, not so. But where this is I don't think it's a big deal being it won't be exposed and all. And less than half of this roof will be used as I see it now anyway. I will have another roof to clean up like this and splice them together.





Mike, But this is what it looked like as I walked out of the garage tonight.





I am thinking it simply needs to be sanded more. I sanded it with a DA and 40, then 80, then sprayed the Ospho and scuffed it with a red scuff pad. I wiped it up sprayed more and scuffed it again, then wiped that up and sprayed it again leaving it.

The bare metal spots you see were right down the middle of the roof. I am thinking that area got sanded twice as much being I did one side then the other.

I have to tell you, I have never worked with anything like this. Here in sunny California I am not kidding you, this is not something I have had to do. But this cab sat out in my wrecking yard behind my garage for almost 20 years. :(

Brian
 
#219 ·
So I got my first use of the ospho today. On the nice clean bare metal it looks great, on the rust, not so. But where this is I don't think it's a big deal being it won't be exposed and all. And less than half of this roof will be used as I see it now anyway. I will have another roof to clean up like this and splice them together.

Mike, But this is what it looked like as I walked out of the garage tonight.

I am thinking it simply needs to be sanded more. I sanded it with a DA and 40, then 80, then sprayed the Ospho and scuffed it with a red scuff pad. I wiped it up sprayed more and scuffed it again, then wiped that up and sprayed it again leaving it.

The bare metal spots you see were right down the middle of the roof. I am thinking that area got sanded twice as much being I did one side then the other.

I have to tell you, I have never worked with anything like this. Here in sunny California I am not kidding you, this is not something I have had to do. But this cab sat out in my wrecking yard behind my garage for almost 20 years. :(

Brian
So, What is your assesment of the product, or is it to soon to tell?

John
 
#221 ·
Sanding with a DA isnt so good ,what you really need is a big ,stiff wire cup on a side grinder..so you get in the pits A Da is just gonna skin over the tops.Try a second application using the wire wheel All your doing is converting it, thats not the goal...You can apply and reapply as many times as you want I usully go three rounds on the tough stuff....I see that kind of rust every day... Thats a pretty good skin, on my 48 you could see daylight through the holes.
 
#223 ·
ospho

I live on the Gulf Coast, Ospho is used by all in the fishing boat industry. Some use it to remove rust stains on gelcoat, some spray it on whinches and places that can't paint. Ospho Does not remove rust, but it does kill it. Lowes sells Rust Kill about $25.00 gal. I buy Ospho at most local hardware stores. Boat supply stores are very expensive. I made a call to Ospho tech support along time ago, they said spray it on let it dry brush off what brushes off paint. No neutralize. I spray it on let it dry, sand it or sandblast respray let dry prime with epoxy. Don't paint over ospho that applied over good paint. Sometimes it takes days for ospho to dry. $12.00 qt. $23.00 gal. Good product don't get in a hurry or you will be messed up. Hope this helps, Steve
 
#226 ·
keep it wet while wheeling .you cant just spray it on and expct it to do all the work.Its a bit like washing dirty dishes...I really like using a pump spray bottle to apply best,and be sure to use it straight out of the bottle dont dilute it.
Being that the roof is upside down it'll hold the ospho like a bowl so your going to have plenty of working time, When your done I'd flip it over right side up and so the access can drain off...
using a side grinder with acid slings it everywhere and will ruin your cloths so wear crappy work cloths and a cheap rain coat or poncho even an plastic apron...
 
#228 ·
keep it wet while wheeling .you cant just spray it on and expct it to do all the work.Its a bit like washing dirty dishes...I really like using a pump spray bottle to apply best,and be sure to use it straight out of the bottle dont dilute it.
Being that the roof is upside down it'll hold the ospho like a bowl so your going to have plenty of working time, When your done I'd flip it over right side up and so the access can drain off...
using a side grinder with acid slings it everywhere and will ruin your cloths so wear crappy work cloths and a cheap rain coat or poncho even an plastic apron...
I scuffed it with a red scuff pad like a mad man! Just learning about this rust stuff Mike, I am not kidding you, when I look at the parts that I cut off the roof that stayed inside......and when I look at the photos at what this cab looked like when I started this project it makes me sick! It was sooooo nice, what a dumb ars I am for leaving it out. But when you have no room, you have no room, crap.

Brian

:(:mad:
 
#227 ·
Sounds like fun........not. I have to tell you, I am going to do this roof but I have decided I really need to get the cab to the sand plaster after I get it welded back together to have the floor and cowl and firewall and underside blasted. I can blast a little as I did on this roof, but damn it kicked my ever loving ****SSSSSSSS yesterday. I am too friggin old for this crap. I want to cut and weld and have fun, this stuff sucks! The real bummer is I don't know how much of this roof I am going to use. I may even use it all, I just haven't decided exactly how I am going to lengthen it, I may just go with adding metal, but I may remove the 2/3 front of it and replace it with the extra roof I have so I don't have to have a metal strip. So cleaning up all the rust in this one is a waste of time, Grrrrrrrr.

Brian
 
#231 · (Edited)
LOL,Seriously ILMAO, Its hard work for sure but I do it every day so Its not so bad ,I learn quite a few tricks over the years ,The Big wire wheel is one of the biggest helps there is ,1/2 hour to an hour tops on your roof,Your really wasting your time using the scuff pad on that... you only use the scuff pad after wards to make sure you havent missed anything...But Basicly the scuff pad is only for surface rust and other contamenets like hand prints etc....
It'll get easier ,I promise. I'm really glad your trying this but dont give up ,YET. This is EXACTLY what the whole thread is about. We'll get you there...
Any questions yet ,come on, ask me something.????
 
#229 ·
One more thing

Heres a perfect example of using it right and following directions...This is a quick summary of how to use it on rust from my post a couple pages back I think it was #210

Heres what I do basicly
,heavy pitted rust......,wire wheel dry first,(to remove the loose stuff), wet and wirewheel again wipe off access,let dry and repete....
.heavy to light surface rust ....,wet and scrub with a red scotch pad,wipe access with paper shop towel ,let dry.....
.before epoxy... sand and use W&G remover twice ...tack and shoot...I always tack it looks better when done but thats just me it isnt really nessacary....I just want all the metal as clean as possible now days I've found that using solvent based AND water based W&G works even better than just solvent based alone....
You want to wipe off as much of the access as possible you want that film but you dont want too much film...it just makes it harder to get off...
I've done a lot of testing after starting this thread and by all means do them yourself and get back to us.
Mike

Brian , This is a great, Your a perfect example
I know your a pro but where did I ever say sand the rust with a DA ???? You see why people have trouble? I can only be sure you have good results if you do it the way I do .changing anything can throw the whole thing off.Now lets start over , dont substitute anything ,if I say paper shop towel dont use an old rag.etc....OK ??? :nono::nono:
 
#232 ·
Heres a perfect example of using it right and following directions...This is a quick summary of how to use it on rust from my post a couple pages back I think it was #210

Heres what I do basicly
,heavy pitted rust......,wire wheel dry first,(to remove the loose stuff), wet and wirewheel again wipe off access,let dry and repete....
.heavy to light surface rust ....,wet and scrub with a red scotch pad,wipe access with paper shop towel ,let dry.....
.before epoxy... sand and use W&G remover twice ...tack and shoot...I always tack it looks better when done but thats just me it isnt really nessacary....I just want all the metal as clean as possible now days I've found that using solvent based AND water based W&G works even better than just solvent based alone....
You want to wipe off as much of the access as possible you want that film but you dont want too much film...it just makes it harder to get off...
I've done a lot of testing after starting this thread and by all means do them yourself and get back to us.
Mike

Brian , This is a great, Your a perfect example
I know your a pro but where did I ever say sand the rust with a DA ???? You see why people have trouble? I can only be sure you have good results if you do it the way I do .changing anything can throw the whole thing off.Now lets start over , dont substitute anything ,if I say paper shop towel dont use an old rag.etc....OK ??? :nono::nono:
I was using my own professional mind with all it's brilliant intelligence. :rolleyes:

Brian
 
#230 ·
I got all I can do to keep from screaming. Ospho is a good product but it's for consumer use. I just went out in the shop took a rusty VW rim that has been laying around for years.I took an old towel laid it on the rim and poured a little Mastercoat rust remover/prep. Elapse time 50 min. down to white metal. Three years ago I wanted a rust remover that I did not have to wait all day like these new keyelation products.I wanted a prep that actually contained zinc and would dissolve surface rust in less than 5 min. without hydrochloric acid. DBM I appreciate all the education that you give and you have all my respect but there are products out there that the average body man never sees.
 
#239 ·
I'm a little new at this I will have to have my daughter post pictures when she comes in on Monday. When I refer to consumer use it means simply that it's available on the store shelf. I bought Ospho every time in Florida every year when I did the Turkey Rod run.It's a great product. I wanted something faster that actually contain zinc . My offer still goes to you and Brian Id be happy to have a sample sent to both of you with the hopes that I would get a fair assessment.In the meantime keep up the good work.PS red shop rags immediately turned black.
 
#240 · (Edited)
Of coarse I'll try it and give a fair assment of it...but you have to realize your up against my favorate product and Its the only procuct that I've ALWAYS used even as good as SPI epoxy is it comes in at my second favorate product but 1st as my favorate epoxy..so you've got some stiff compitition.
...............................................................................................................................
The rags turned black but the rusty wheels turned clean steel ??????

......................................................................................................................
Ive had an idea I'll bonce off you and the other members.
one of the biggest disadvantages of sandblasting is the mess gets everywhere so everything has to be takin apar tand just an empty shell can be blasted...Right?
Mixing the abrasive with a liquid would make an abrasive slurry that would be easier to use on a Daily driver wouldnt it....
I wonder If anyone has ever mixed Ospho and blasting media to make a slurry that when your done blasting, the steel wont rust....Hmmm
 
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