Hot Rod Forum banner
Status
Not open for further replies.

The Ospho Solution..(rust removal)

353K views 664 replies 61 participants last post by  Lizer 
#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.
 

Attachments

See less See more
4
#246 ·
Its actually more accurate to ask...... How many tried SPI and and switched to something else???? when something comes accross that is better I'll use it ...something tjhat has all the qualities of SPI epoxy that you can weld thru would be great but I'm not holding my breath...you think I want to do things the hard way? Heck no...
Heres some old pics showing what you need for heavy surface rust(No pitts) ...All I did was spray some ospho on ,scrubb it in with a red suff pad and wipe off with a paper shop towel (CLEAN ONES):nono: Took about a minuteand you can see the rust running off as soon as it hits the rusty steel ...I dont understand why you guys are having such a hard time with it..
 

Attachments

#251 ·
There is no question in my mind it will do exactly what you say on rusty metal Mike. The question I think Brian and I have is how to easily clean old heavily pitted rusted metal. When you have deep pits I doubt even a cup wheel gets to the bottom of them. I have used Rust Mort for years and I do not doubt that Ospho could be better but I do think that the challenge with both products is:

First, to reach the rusty areas in the bottom of the pits and getting the rust loose so it is removed and not just the surface converted.

Secondly, Once the metal is clean to make sure it is neutralized and there is no acid left that can effect the Epoxy curing.

I really appreciate both your input as well as Barry K's. If it weren't for Barry coming back and explaining that the issue with using an acid is the problem with getting it properly neutralized there really would be a lot of confusion at this point.

Potentially, the Ospho has all kinds of value to the project I am working on.

John
 
#254 ·
My point also..... as I said I'll give it an honest shot but the bars been set pretty high...I've tried quite a few in the past and if something comes along thats better ......well you know me ....and my big mouth....I'll be starting a new thread telling everyone all about it just like I always do....You gotta realize something, these two products are THE most important step in doing a quality job that lasts, so having the best is very important.... Way more important than my pride or just being right, if im wrong I'll be the first to admit it...I've never went along with the clan just because I'm a member as a matter of fact if I can see through the Empirers new cloths I'll stand up and say so, thats one thing everyone can always count on with me...
 
#249 ·
It gave me a flash back to the time I poured toilet bowl cleaner and bleach in my sink at an apartment I was living in 25 years ago. I will NEVER make that mistake again!

Brian
 
#252 ·
About 6 years ago I had a lab tech who was measuring out some formaldehyde. She was a very good tech, but spilled a bit when pouring it out. I bet she didn't spill more than 20-50 ml and we had to evacuate that entire half of the building lest your mucosa get burned away and permanently preserved.
 
#250 ·
Sometimes the rust grows over the paint film like a algae. You would bet $100 that there's absolutely no paint on that panel when you spray paint remover against it the paint it comes to the surface then acids will work I spent many years sharing a booth with Capt. Lee and he sold Rust away and Metal prep these two were excellent products. Sometimes he we get a display and the rust would not budge As for pitting the acid will clean it up nicely and follow it with 2/3 coats of Mastercoat Primer/surfacer then K200 and your topcoats. this is how you treat hoods , roofs and deck lids.
 
#253 ·
Thank you Lizer for the honorable mention its appreciated I hope someone will PM me with a rusty hood thats pitted so I can show you how to level it all up without the use of any kind of fillers. Brian would you be willing to spray some pitted sheet-metal to demonstrate this for me. If you have some junk behind your house I'd like you to apply a couple of coats and throw it back outside for a while
 
#256 ·
That's what I plan on doing, and painting right over the Ospho like they say in their tech sheet. There is nothing but nothing that show you what a product is capable of than abuse. If it holds up to abuse, without the abuse it's a sure thing right?

Brian
 
#258 ·
One of the thing I want to make clear here. Just as Mike (Deadbodyman) has done here, and made it very clear. There ARE people who are going to go out and use these products. There are posts on every forum on the net about products like these along with the magic paint products like POR15. IF one of these products is going to be used, and we know it will, why not make sure it's used properly? I have fought and fought it, but with Mike's description of Ospho damn it, he is convincing, one he isn't peeing in the wind, he REALLY knows what he is talking about. And that isn't just because he has used it, that means CRAP to me, so what you have done it a million times (like the sanding the basecoat discussions) but what he says and how he says it convinces me there is way more to his words than just "I did it and it works", MUCH more to it.

So I am open to see this, I am not going to take it for granted and paint over it on my hood, I am going to take this very seriously as it CAN cause catastrophic failure. And it doesn't happen next week, your finished cars paint can fail in a year or two, I do NOT want to have anything to do with that! So I am taking it slow, and I am going to listen to what Mike says about it and follow this closely.

And what Pat is saying as well, we are going to learn something here.

If you have any doubts, or more importantly, you SHOULD have doubts. If you use these products thinking they are magic and you don't have to follow the rules, you are going to be very disappointed.

I just wanted to make this clear.

Brian
 
#262 ·
Yep, that is the part I like the most about the idea of using Ospho, I am on my way out to the garage to wire brush my rust as instructed by Dr. Ospho (Deadbodyman).

Brian
 
#264 ·
OK Mike. Don't be too hard on me for comparing apples to oranges. I have a bottle of Rust Mort but no Ospho so I played today with what I had.

Picture one is of an untreated brace and one that was wire wheeled and treated with rust Mort.



The next picture shows the treated support in such a way you can see where some of the metal has been cleaned to shiney silver metal.



This last picture shows what is under the black coating when I scuffed it with a piece of 40 grit paper.



There is indeed still rust under the black coating which indicates the Rust Mort did not convert it all the way through in all places .....BUT, The rust is not under all of it. You can see where I uncovered shiney metal in places. I believe that retreating tomorrow will get rid of most of the remaining rust and for sure doing it tomorrow and tne next day would..... NOW, If Ospho is indeed stronger than the Rust Mort it would appear to me that Mike is right and this could be a very successful treatment for some pretty heavily rusted metal.

This is kind of exciting.

John
 
#265 ·
John, here it is for 10.36 a quart.

Mike, ok, I re-wet a section of roof and wire wheeled it. I don't have a small grinder anymore (loaned it to my brother when I closed up my shop and he wore it out!) do I got one for my drill. This is a stiff bristle wheel and with my drill I could really bare down on it so I have to assume this is good enough. If you think I need a real grinder I'll get one, I guess it wouldn't hurt anyway.







But it really didn't look like the ospho was removing the rust any more than if I just wire wheeled it without the ospho. Nothing magical was happening that's for sure. But the I guess it's going to "convert" it when it goes black and that's good enough on this particular spot anyway huh?

I did a couple of test panels I plan on epoxy priming one and bringing the other to work to have them prime and paint it. Then I will be doing a scratch test and see how it holds up. At that time I will throw it up on the roof and see how it hangs in there over time.



Brian
 
#266 ·
there's a huge difference between a wheel on a drill and on an angle grinder. I see you're using a pneumatic drill so I don't know how much faster that spins than the corded DeWalt I used to use. However, it is no match for a 12,000 rpm angle grinder. That will remove a lot more rust a lot faster and better than something on a drill. I bought a cheap Black and Decker angle grinder, you can get them for around $30. It was practically disposable. I'm on my second one now though.
 
#270 · (Edited)
I gotta make this quick because I'm running late this morning...Brian you'll need those smaller wheels later on and for edging and tight spots I have a whole collection of wire wheels the problem you might be having is the bristles arnt stiff enough and the drill is too fast and just polishing the rusted spots...try slowing it down and really pressing it down into the pits...get the black out..but you wont get shiny steel on a lot of it ...,it'll be darker but not black...heres a pic for you to compare...to zoom in click the last pic then clic again you can see the pitts clearly thats ready for primer....if your trying to get it to look like new steel your wasting your time but whats NOT badly rusted sure looks like new steel...
John that rust mort seems to be working pretty well I dont know which is stronger the reason I prefer Ospho is because when I used it everything turned black even the good metal mabee I did something wrong back then it was over 15 yrs ago so I may have to revise my opinion of it....
 

Attachments

#272 ·
I gotta make this quick because I'm running late this morning...Brian you'll need those smaller wheels later on and for edging and tight spots I have a whole collection of wire wheels the problem you might be having is the bristles arnt stiff enough and the drill is too fast and just polishing the rusted spots...try slowing it down and really pressing it down into the pits...get the black out..but you wont get shiny steel on a lot of it ...,it'll be darker but not black...heres a pic for you to compare...to zoom in click the last pic then clic again you can see the pitts clearly thats ready for primer....if your trying to get it to look like new steel your wasting your time but whats NOT badly rusted sure looks like new steel...
John that rust mort seems to be working pretty well I dont know which is stronger the reason I prefer Ospho is because when I used it everything turned black even the good metal mabee I did something wrong back then it was over 15 yrs ago so I may have to revise my opinion of it....

That is exactly what I was thinking, they are pretty stiff, as they were the stiffest they had in that 1/4" mandrel driven wheel. They have stiffer ones with a 3/8" (or is it 7/16"?) for the small grinders I think. I don't have a single tool that uses it so I got the one I did. My only working electric is a MONSTER I use for the shrinking disc I don't even want to think about using for this. But I'll get myself the smaller electric, I need one anyway.

Thanks guys!

Brian
 
#273 ·
I see it, and that is what I am getting if you look at what I have done. But damn it's still a lot of work, no magic yet. I am hoping Skyco comes out with a magic wand that takes away the rust, that's what I am thinking we need.

Brian

 
#274 ·
You would not believe how gitty I am right now! A solution to this whole friggin thing just hit me! In the midst of working on this roof and having it kick my ever loving butt it hit me that I am more than willing to open up my wallet and have the floor and firewall sand blasted at the local blaster. But how the heck will I have it done, mark off the panels I don't want them to touch, ok, but I want the bottom of the floor done and how will I have them do that, roll the cab over to do it? Do the floor first, get it back and epoxy prime it, then bring it back for the rest? Then it hit me this morning, add a couple of braces of tubing up off the cart I made for the cab and bolt the cab to it leaning on it's back! WHOOO HOOOO, holy schimmolly what a great idea!

I'll do the roof and get it all welded on, then modify the cart to bolt the cab laying on it's back up off the cart. Put it on the tow truck over to the sand blasters, they blast the floor underside and top, cowl inside out, the door jambs, then I bring it over to the shop and epoxy prime the whole cab in the booth, WHOOO HOOOOO!

Back to your normally scheduled thread...........

Brian
 
  • Like
Reactions: John long
#275 ·
Okay DBM here are some photos like I said earlier at about the 50 min. mark. Notice my red shop rag turned bluish black. Years ago with a lot of rust treatments when it turned black you had this scratch it to make sure there was no rust beneath it. I don't see that anymore on the directions. You just can't beat white metal and a little zinc residue to combat rust. I take it a step further I seal it with an airtight seal followed by an automotive primer then paint. I call the double whammy.
 

Attachments

#277 ·
Ok Mike, I was going to stop by HF and get an angle grinder but you know how I feel about that place. So I went over to my REAL hardware store in town and the guy gave me a discount on a Dewalt 4.5 inch angle grinder for $49.99, so now I need to know which wire wheel.

One like this, super aggressive "knotted wire"



Or the little tamer one like this.



These suckers aren't cheap so I am asking instead of just buying blindly.

Brian
 
#278 ·
I was just looking for some grinding wheels on line and came across a discussion on these little grinders and I was thrilled to see that the cheapies can vibrate a lot and guys switching to a quality grinder and it's gone. I sure as heck hate to save three dollars and 29 cents to work my body harder, it just isn't worth it!

Brian
 
#279 ·
yes, exactly! When my B&D dies I will get a better one, like DeWalt. I got a second B&D because I thought I made it leak grease by just using cheapie brushes that weren't balanced well, and this threw the rotating mechanism all out of balance and ruined it. But my second one is starting to leak grease in the same areas and I haven't used it that much. I've used expensive ones (like DeWalt) before and they are smooth.

Also, don't get the cheapie wire wheels because they aren't balanced well. And make sure the wire wheel you get is rated for the speed of your grinder, sometimes they're actually rated slower.
 
#283 ·
HELL YES I would, exactly, ok I am sold. They had one attachment, "diamond grinder" or something like that. It's for grinding concrete and stuff like that. I guess it almost never wears out?It looks like solid steel and it's $70! The guy (who I know and trust) told me he has one and it's the cats meow.

Brian
 
#291 ·
OK, If it is true confession time I buy the 4 1/2 inch Chicago Electric orange grinders when they are on sale at HF for 18 dollars. I have one I keep a flapper wheel on, one with a cutoff disk, one with a grinder stone and one with a wire brush. I have one new in the box in case I need a quick gift or replacement. I have only ever had one die. They have been excellent little grinders.

On the other side of the coin I would advice never ever by the Drill Master. They are not worth carrying home.

John L.
 
#302 ·
Say what you want about HF tools but having a dedicated tool for each job is so much faster and easier than changing every time you need a different attachment its crazy ,it something you'll never miss unless you've been there...I only have three side grinders John but I have so many of those 9.99 die grinders its not funny.mabee twenty or so and each one has its own tool all I do is reach in the drawer and get a different one when I want one theres no swapping or trying to find different wrenches to get the chuck loose ....its sooooo much easier ...I have an air drill from there that I've had for years and use all the time, the only bit thats ever been in it is an 1/8" double ended bit.I never would have been able to know how much faster it is if it wasnt for HF tools you can have a tool for every bit...
 
#295 ·
I retreated the body mount channel tonight. I wire brushed it good. Then I applied the Rust Mort with a spray bottle and scrubbed it in with a Scotch Bright pad. I then wire brushed it again and wiped the excess off.

I was pleasantly surprised how little brown rust I found when I cleaned it up before I treated it tonight.

Also, I did put the wire brush on the air grinder. the only issue ith that was the wire brush is standard thread and the air grinder was metric. Surprize, surprize. I did like being able to control the speed of the air grinder though.

John



 
#296 ·
O-KAY, I got some rusty worky done tonight, nothing magical so far.

I picked up this device at HF.....$5



An example of it's work.



I got this monster at the hardware store, $13



Just for fun I tried this, these little buggers always do a good job for me, it was close to worthless on this rust.



Ok, I have to say, I am lost, as far as the magic goes, it ain't happening. The wire wheel seems to "polish" the metal and not do a whole lot at all, which has been my experience in the past as well. The HF scuff wheel thingie, that sucker seems to do the best hands down.

I did go over the rust with the wire wheel and could get some of the looser stuff off. But then it took the scuff wheel thingie to really get the rust off.



This is that same spot that I have posted photos of the last few days.



Ok Mike, I don't get it, spraying the ospho doesn't seem to do anything for me. Maybe it's this rust, I know it can be different panel to panel or what not. But it really didn't seem to change much, I tried it under a number of different conditions, but just hitting the metal with the scuff wheel seemed to win hands down in removing the rust.

Brian
 
#297 ·
#300 ·
Thats true ...back then they used red oxide primer,its hard to tell whats rust and whats primer so that needs to come off one reason you want to wire wheel dry first...on vynil top cars ,many times I'll use a stripper first and wheel it while the primers soft ....Ospho wont touch paint and primer as far as removal goes...
 
#301 ·
Brian ,are you wheeling the rust while wet with the Ospho??? it needs to be wet.
using a pump bottle wet it down good and wet, then start wheeling ,rinse all the nasty stuff off with more (clean) ospho and wipe off all access with shop towel... are you spraying it on and letting it dry THEN wheeling it??? I'm at a loss as to why your having such a hard time with it...As a side benifet, you may have found something with those scuff wheels I'll have to try them. When it comes to the side grinder you want POWER not speed, the more speed you use the more it just polishes,the bristles are just skimming over the tops and not having a chance to drop down into the pits... get it going as slow as you can..
 
#307 ·
I am spraying it on and wheeling, I just don't see anything different than wheeling it dry then spraying the ospho on to protect it. All I know, is so far that scuff thingie is kicking that wire brushes butt big time!

Brian
 
Status
Not open for further replies.
You have insufficient privileges to reply here.
Top