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Discussion Starter #1
I have a 40 Chevy coupe I recently puchased. The previous owner chemically stripped the car over a years time without cleaning off any of the stripper residue or priming the metal after stripping. Now I have splouches of pitted rust on the car. Is there a recommended chemical that i can use on the rust. I tried muratic acid on a spot and it turned it yellow. I really don't want to sandblast if I don't have to. I have been buffing it with a 80 grit sanding disk but I am afraid the pitting will came back after a time.
Thanks for any help you may be able to give.

Totter
 

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Contact POR 15 they make products that will seal the metal and prevent further surface rust. Their phone number is 1-800-457-6715. I am sure they have a website if you just dink around you will find it. GOOD LUCK Dave E Shank
 

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the por stuff looks just like the rust reformer i've used in the past. napa carries their brand, i'm sure many other places will also have their brand name of the same thing. just knock off any scale, dirt, etc, have a clean surface, coat with a brush or rag, let it dry, scuff it smooth with some sand paper being careful not to go too deep as to take the product out of the pitted area. then primer or bondo as needed. it works great, i've used it around window frames on a couple of elcaminos i've painted. good luck, dan
 

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Okay, if i have a bare metal car and it has some spots of rust like that, this stuff will remove it and it won't come back? and then can i just go and do my painting?
 

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I had a VERY long and informative article on this typed in and was ZAPPED out of the discussion for some reason or another. I will retype it in word format and post in a little while. :) I think it might have something to do with the endless pop up adds for gambling, etc :mad:
:mad: :mad: :mad: :mad: :mad: Johnny

[ July 28, 2002: Message edited by: johnny 1986 ]</p>
 

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Discussion Starter #8
Thanks for all the replys guys. I plan on priming this thing with PPG DP90 when I get the rust under control. Is that compatible with the different things you all are suggesting.
Johnny 1986---I,m looking forward to the article you are going to write.
Don Meyer--- this OSPHO that you talk about. Where can you purchase it. I think it might be on the right track. everthing I have read talks about treating the rust and covering it with a phosporous coating.

As I said earlier, I tried Muratic acid on one spot. Now I can buff it back off to bare metal and the next day, it's back to it's yellowish rusty look. I thought I read someplace that you should wipd it down with baking soda and water to neautralize it. Has anyone have any info on this?

I have used the por 15 product on the underside of a 69 Firebird that I am also doing. It is a great product but I don't know if I want to coat the whole exterior of the coupe with it. I'm not sure of the reaction with the DP90 and I think I read somewhere that it has some bad reactions to ultra violet rays If not coated right away.

I have also seen where Eastwood has a product called Oxisolve. It is also suppose to tansform
rust into good metal, onse again I think this is bacause of that phosphate coating that Don Meyer was talking about.
 

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All the above posts are correct. I will add to them as I did before, but got shut out for some reason or another. Here we go.
My first and most important message to relay is to do your project “a panel at a time” The reason for this is you will end up with a much better job and you also will not get tired of it and settle for second place. Always remember SECOND PLACE is the FIRST LOSER. Back to the car. Start by getting some REAL GOOD CHEMICAL RESISTANT GLOVES & SAFETY EYEWEAR of some kind. You sure don’t want to have EYE PROBLEMS when your finished. Next get the roughest Scoth-Brite (red) and either Comet, Bonami or Ajax and scrub with it and water until you end up with a surface that the water does not bead up ANYWHERE. At this time, you can pick out any rust scales that might be present and proceed. The nooks and crannys are the most important if you want all your hard work to show up in the end result. This is referred to as a “waterbreak free” surface in the aircraft industry. This process is used on all aircraft from the small crop duster to the space shuttle. Once you are at this step, grab a new or “soap free” piece of Scotch-Brite and scrub with clean water from the water hose if possible. If not possible, be sure to have A LOT of water jugs on hand. Remember the water break free surface, this is the MOST important step in your project! It insures anything that is on top of it will adhere to it and anything added on top of that will adhere also. Do not let this air dry, I have found that CLEAN shop air is the fastest,easiest and best. Make sure it is CLEAN! By this, I mean, If you blow dry it with an air compressor that does not have a drier or moisture trap on it, you will just be blowing compressor oil on the surface and nothing sticks to oil.
The next steps will be referencing Dupont products as that is what comes to mind. I know I will hear some rebuttals on this, but “chemicals are chemicals” I am aware of some seeming they are watered down and quite possibly so. It is not my intention to endorse one or the other. Once you have arrived at a dry, clean surface, get some phosphoric acid. (some trade names as follows: Ospho, Metal-Conditioner (Dupont), Metal-Prep(PPG). There are a lot of others, just make sure the label states “PHOSPHORIC ACID”. Follow the instructions to the letter on the dilution and while your at it PUT ON THE SAFETY EYEWEAR I have already mentioned. Start scrubbing with the solution following the instructions on the label. Do not let this solution air dry nor dry it with compressed air. Once you are at this step, you can go get some Vari-Prime(Dupont) and spray this on as per the label. Don’t figure “more” is better, it is not. And if you disregard this, you will be real sorry and your billfold will be thinner and also you will have to go buy more Scotch-Brite,etc and start all over again! This is a two part catalyzed primer and is most definitely dangerous to your health. WEAR A RESPIRATOR that is compliant for the chemicals being used. Once you are at this point, you can start doing the required body work as in filling small imperfections, rust pits, bondoing very small dents and so on, at your leisure. ONE panel at a time. Can you imagine trying all this on an entire vehicle? You would either have a bunch of money tied up in a project that is not good or you would have a number 2 job. Always remember: Second Place is the FIRST LOSER. I hope I have not bored anyone with such a long answer to a “seemingly” simple answer. There is a lot more to the Autobody business than a lot of people believe. If there is any typo's it is because I did not want to take the chance and get shut down again. Anyone can reach me at

[email protected]

Johnny
:)
 

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Discussion Starter #10
Johnny:

Thanks for the info on the rust. I ahve printed it out and am putting it in my file. I do have a couple of questions for you. You state that after you scub it with Phosphric Acid, not to let it air dry or use compressed air. How do you get it dry?
Also is there a reason you recommend Dupont Vari-prime. I was planning on useing PPG Dp90 which is a two part Epoxy primer.
As I said before, I wipe down part of one fender with Muratic acid. Do you know if scubbing it with Comet or Bonami will neutralize it. Right now it keeps turning a rusty yellow.
Thanks
Bill

P.S. There are some nice programs out there on the net that are free to stop the pop ups.

[ July 28, 2002: Message edited by: Totter ]</p>
 

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I havn't been noticing any pop-ups at all... Anyway, i know my chemisty and water will dilute the acid with just a bit, but then will be neutral. Only thing is that water on bare metal makes rust, maybe that is where the baking soda comes in on that one. I am not sure what muratic acid is exactly, but as with any acid, the more water it is in the weaker it gets. At the same time however, if it isn't in any water, it will no longer be an acid and become a compound and maybe the yellow is from the stuff turning into a poweder as you let it set and the water evaporates off. Or the acid just has a residue left behind and a good flushing is in order. Good luck.
 

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Discussion Starter #12
Thanks for the response Croz. I am going to try the method that Johnny posted earlier in this thread. I will let everyone know the results.
Totter

[ July 29, 2002: Message edited by: Totter ]</p>
 

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Teh reason to use Vari-Prime is that it has an acid additive and is an etching primer; actually eats into the surface slightly and makes a very good base for future coats. That is why you omly need a very light coat. Follow it up with your epoxy and then build/sand primers and you will hve a bullet proof base for your color.
 

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Jonny, PER PAINT SCHOOL:
1. once dn to bare metal,wire brush all the rust off that you can
2. OSPHO(can get from NAPA) the surface
3. wait 48 hrs
4. DA all the the surface
5. prime w/PPG's DP primer
I would recommend that you go to your local PPG supplier & ask them. for all the products they recommend get a spec sheet......Don
 

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zerorust.com Iam painting my whole truck with this. I have tested it and it works. POR-15 has some bad stuff in it if you inhale it your DEAD. ZeroRust is easy to use thin it and spray it even on rust. Whats left in your sprayer you can pour right back into the can. Good luck!
 

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Discussion Starter #16
Well guys, this is the route I decided to take.
First I took a 80 grit grinding disk on a electric buffer (1750 rpm) and lightly ground the whole coupe being creful not to put big grind marks in the metal. Then I took ti outside and sandblasted around the all the hard to get areas and any spot that looked like it was deep pitted rust. then I took a da and 80 grit da paper and went over the fenders, and trunk ( I have these parts removed). Then I took and scrubbed the parts with a sos pad and bonami. Then I applied ppg's dx579 with a scotch brite, waited 2-3 minutes and then rinsed off the parts and then repeated the process with ppg's dx 520. Let this sit for 1-2 minutes then rinse and DRY. Then I used Variprime on all the parts. Tonight I hope to get the body done and then coat the whole thing with epoxy primer. This may seem like a long tedious process but I figure just material for the topcoat will coat me about a $1000. I plan on useing a candy apple red and anypody that knows anything about paint knows how expensive that is. Anyway, the paint is only as good as the substrate under it.
If anyone has any other suggestions or think I went to far on the way I did this I would be interested in hearing from you.
Totter
 

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I have to second Maverick's opinion - check out Zero Rust. No isocyanites in that stuff and it's a LOT cheaper.
 

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Sounds like you will have a damn good undercoat the way you have ended up doing it. You already know candy apple red is a lot higher than some others. I guarantee you it usually takes twice as much damn near every time. I have sprayed a ****load in the last 30 years of fancy paint and bodywork. And a bunch of very hard hit totals. I'll try to check the site more regular but if anybody needs some information in the middle of something, they can e-mail to [email protected] I check it more regularly

[ August 14, 2002: Message edited by: johnny 1986 ]</p>
 
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