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Long term primer coat

Discussion in 'The Hokey Ass Message Board' started by mercjoe, Nov 22, 2007.

  1. mercjoe
    Joined: Aug 17, 2006
    Posts: 1,377

    mercjoe
    Member

    Wax over primer ? that sounds rough. I think I'll pass this one
    How often did you have to wax it ? no chalk ?

    Thanks
    Diego


     
  2. overspray
    Joined: Jan 14, 2003
    Posts: 1,429

    overspray
    ALLIANCE MEMBER

    Sorry guys, but this thread has some scary advise.

    For you guys that are convinced on epoxy, please do some more reading on PPG's website and others. The DPLF primers do not have the solids to provide protection from chemicals and weather. If you spend some time looking at some of the industrial epoxy primers available from PPG and other manufacturers, you will find products with 4-8 times the solids content and more protection from salt, chemicals, UV and moisture in a good 2 part epoxy. Also, the amount/thickness of the coating is critical to the protection. 2 coats of DPLF ain't squat (about 1 mil). You need lots more to give adequate protection.

    Putting wax on a pourous product like primer will impregnate wax, silicones and oils into it. This will usually end up a nightmare later requiring stripping everything off to metal. I do see the point of doing this "back in the Day", but that was then. (Deuce coupe bodies were about $50 bucks, too.)


    If I was in Brazil (and was fluent in Spanish to read the tech sheets) I would check with companies that provide primer and topcoats for building steel, like bridges, storage tanks, ships and other structures that need to be protected from the weather. See what would be a good product then horsetrade with the applicators (painters) for enough product to do the car. You should be able to come up with a good 2 part paint or primer in low gloss that trips your trigger color wise, chock full of lead, chromate and other good stuff that we in the states have have legislated out of our products and made our domestic coatings less than they used to be.

    overspray
     
  3. mercjoe
    Joined: Aug 17, 2006
    Posts: 1,377

    mercjoe
    Member

    Hi Spray,

    So, what do you recommend from PPG ?


    Thans
    Diego
    PS: Brazil = portuguese, Argentina = Spanish.
    Not the same country ;)

     
  4. overspray
    Joined: Jan 14, 2003
    Posts: 1,429

    overspray
    ALLIANCE MEMBER

    Ahhh yes--I did remember after I posted---Portuguese.

    If PPG is available and you think an epoxy will fit the bill-

    here's one that has 3 to 4 times the build per coat of DPLF:

    http://www.pwpaints.com/images/downloads/dep351-fl305.pdf

    You can still do better than the 351 epoxy. I couldn't get into the PPG site to get the other primer numbers. Try the PPG site later on. There are several PPG primers used in fleet aircraft and industrial applications with much higher solids as well as other manufacturers (Dupont-Sherwin Williams-BASF-Akzo-Nobel-etc) that have world wide distributor networks.

    When you read a product information sheet look at the:

    Lbs per gallon of solids-the higher the solids content usually means more corrosion protection as well as fill.

    film build per coat (dry)- 5 mils or greater per coat is really thick and more thickness means more protection. Look to get around 6 to 10 mils total for good protection. This also gives you something to sand on later.

    dry time/must be sanded to recoat or apply topcoat- if the cure time when it needs to be sanded in order for good adhesion of a topcoat is short, the resin probably has good chemical, moisture, and solvent resistance. Some of the chemical, moisture, and solvent resistance information may also be listed on the sheet.

    I mentioned primers for steel, ships, bridges and tanks, because those coatings are made to withstand more weather and abuse. It should also make you think outside the box of automotive paint and primer.

    If you find something local, with a tech sheet in English, email me the link and I'll try decipher it enough to see if it's a viable choice.

    And when you get right down to it--Paint is the best "primer". As someone already mentioned, a good quality 2 part single stage urethane topcoat (flattened if you like).

    I like to get everyone thinking about other products and possibilities. It helps on the learning curve and keeps you from getting in a rut on one type of product.

    overspray
     
  5. mercjoe
    Joined: Aug 17, 2006
    Posts: 1,377

    mercjoe
    Member

    Thanks for all the advice spray, but in a few words, if paint is the better primer I shoul really consider using a single stage black paint/flat clear over the red oxide and forget about the epoxy primer ?
    I know my red oxide foundation is not good so I wanna go with the cheapest solution. Should the paint/clear be much more expensive than the epoxy primer ?


    Thanks again
    Diego
    PS: Im in Argentina !!!! not Brazil !!! ;)




     
  6. Slide
    Joined: May 11, 2004
    Posts: 3,021

    Slide
    Member

    I'll agree with overspray on this. Paint is definitely the best "primer" if you are going to drive the car in "primer" for more than backing it in/out of your garage. I re-primed my 52 sedan several times due to the chalking and fading. I drove the car every day and it sat out in the Texas sun all day while I was at work, so I'd get about 2 months from the old DP (before "LF") primers, but then I went to PPG's K93 tintable primer, which uses single-stage colorant to make relatively dark colors possible. I did that 3 times, each time using a higher concentration of colorant vs. primer, and each time it lasted longer. The last time I shot it, it was almost entirely basecoat, and it still looks good in the hands of the car's present owner (though he doesn't leave it out as much as I did).

    Primers don't have UV protectors built-in, so there's your worst enemy when it comes to keeping your stuff look good. I highly recommend running some flattening agent in some single-stage paint (in any color you choose!) if you think it might be a while before you get the car painted "for real". The only issue is, with darker colors, it's hard to match the same "sheen" when doing spot repairs. On the other hand, you can control how flat/satin/semi-gloss you want it by varying the amount of flattener in your mix. You can make black look so flat your car will look like it's covered in soot, or you can go with a more satin or semi-gloss look.
     
  7. mercjoe
    Joined: Aug 17, 2006
    Posts: 1,377

    mercjoe
    Member

    Thanks Slide,

    The flatenning agent, besides flatening the paint, has any
    protection capablities ? sorr for the stupid question, but Im a total ignorant on paints, I already said that I think :eek:

    Thanks !!
    Diego

     
  8. mercjoe
    Joined: Aug 17, 2006
    Posts: 1,377

    mercjoe
    Member

    I'll go with black PPG DPLF90. I think its gonna hold ok over the red oxide for a year or two.

    Thanks all guys
    Diego
     
  9. Slide
    Joined: May 11, 2004
    Posts: 3,021

    Slide
    Member

    No offense, Diego, but you might need to go back and read what others posted in this thread if you need a year or two (which usually means 3-4 years for most people!) from your primer. DP90LF will degrade faster than any primer I know of. It does OK as a sealer coat under paint, and prevents rust while you have the car in the shop working on it, but that's about all it's good for.

    For what you are saying you want to do, I think you could find a much better product for much less money (unless PPG products are much less expensive in Argentina than they are here in the US).

    If you just want flat black, ask your paint supply store for the stuff they use to paint Muscle Car hoods or the headlight nacelles in mid-1980's Mustangs & Camaros. It's usually a satin black paint, but it will hold up to UV, and it will be relatively easy to paint over it when it comes time for the final paint job.
     
  10. SlowandLow63
    Joined: Sep 18, 2004
    Posts: 5,958

    SlowandLow63
    Member
    from Central NJ

    I never thought of anything like that. I started on DP-90, when it was still tougher than it is now, and then moved on to HOK 2-part epoxy primer which I love. I think it builds 3-4 mils per coat which is fine with me. High solids and easy sanding. I don't think I'll ever switch again, but I never though to think outside the automotive box.

    Mercjoe, I missed the part where you are looking for 1-2 years outside from the product. You might be better of with a single stage flattened product. The recoat won't be very hectic if you use a decent product. I just don't think DP-90 will hold 2 years outside.

    To keep it cheap, order OMNI MTK. Its single stage and cheaper than PPG and will definitely hold 1-2 years or more. OMNI is a line from PPG and if your dealers stock PPG they probably stock OMNI. Tell the rep you want it in semi or flat and all you need to do is spray. Its almost exactly like Hot Rod Flatz without the price or the name.
     
  11. MCjim
    Joined: Jun 4, 2006
    Posts: 1,163

    MCjim
    Member
    from soCal

    Two year old DP90

    [​IMG]
     
  12. mercjoe
    Joined: Aug 17, 2006
    Posts: 1,377

    mercjoe
    Member

    I now Slide, Ive read all responses but Im really sonfused at this point. The paint shop guy says the epoxy primer will give much more protection than paint.....



     
  13. old wood 51
    Joined: Aug 26, 2007
    Posts: 368

    old wood 51
    Member
    from NAPA CA.

    ...epoxy primer will protect bare metal ,better than paint over bare metal,.paint will protect better over primer; what is under the red oxide? bare metal or old paint? if you want to go cheap try industrial type paint. can you get AKZO sikkens paint down your way? (not cheap) BTW chroma-one is Dupont single stage. "paintjobs are only as good as the prep underneath"
     
  14. mercjoe
    Joined: Aug 17, 2006
    Posts: 1,377

    mercjoe
    Member

    Hi Old W,

    There's nothing under the red oxide..., metal. the eopxy over the red oxide will fail protecting the metal ?

    D.


     
  15. overspray
    Joined: Jan 14, 2003
    Posts: 1,429

    overspray
    ALLIANCE MEMBER

    Must be a salesman--he sure does not understand paint or coatings.

    Get some less expensive paint (single stage-with flattener if you like) 2 part, with a hardner/catalyst, and pick out a shade you like. You are probably going to have to start over after the 2 years or so, and strip it in order to do a good job.

    What brands of paint are available to you and can you paint?

    overspray
     
  16. mercjoe
    Joined: Aug 17, 2006
    Posts: 1,377

    mercjoe
    Member

    That I can remember Sherwin williams, PPG.



     
  17. overspray
    Joined: Jan 14, 2003
    Posts: 1,429

    overspray
    ALLIANCE MEMBER


    Both of these companies should have a good single stage paint with hardner that will do the job at moderate cost. Find out what's available and post the information. The preparation for, and application of the paint will be the next things you need to address. Since you are in "IT", you should be able to research some information and bring back some questions here, to help get you on track. Whether you spray yourself or not you should gain some knowledge.

    overspray
     
  18. mercjoe
    Joined: Aug 17, 2006
    Posts: 1,377

    mercjoe
    Member

    I want to get some knowledge for sure OS.

    Cant find much info on paint stores sites.. , actually no single stage paints. I'll call tomorrow and post what Ive found.

    Thanks a lot
    D.

     
  19. mercjoe
    Joined: Aug 17, 2006
    Posts: 1,377

    mercjoe
    Member

    Now Overspray, explain me one thing. Is the single stage paint better in my case because of the red oxide or is it always better paint than epoxy primer ? (I mean for this kind of SOS paint jobs). I guess the epoxy primer would be better if the body was bared as another HAMBER posted earlier today.., is that it ?

    Thanks
    D.


     
  20. Ratherman
    Joined: Feb 23, 2007
    Posts: 145

    Ratherman
    Member
    from WI

    Here is purple-tinted primer - sorry - it's been 20 years - don't remember the brand - with a clear coat and dulling agent. Makes it nice to clean/wipe off...

    P6103707 (Medium).JPG
     
  21. SlowandLow63
    Joined: Sep 18, 2004
    Posts: 5,958

    SlowandLow63
    Member
    from Central NJ

    In lieu of Overspray, the single stage is better in this case because you are looking for somehting to seal out moisture which epoxy primer can do only for a short time. The only thing that has to do with the red oxide is that you don;t know whats underneath. Other than that, it really has no affect.

    You start with bare steel. You need something (epoxy primer for me in your case the red oxide and whatever is underneath) to adhere to the bare steel, then you apply a surfacer to bridge the gap from primer to topcoat. This ensures good adhesion of your topcoat. Then you topcoat which seals everything from moisture, UVs, etc. In your case you can skip the surfacer because its only temporary.
     
  22. mercjoe
    Joined: Aug 17, 2006
    Posts: 1,377

    mercjoe
    Member

    What about some clear over the epoxy primer ?
     
  23. overspray
    Joined: Jan 14, 2003
    Posts: 1,429

    overspray
    ALLIANCE MEMBER

    By George--I think he's got it!


    Clear over primer is more work and expense with less results--for what you are trying to accomplish for a short term coating.

    A lot of guys are really for epoxy primer, but very few realize that there are so many epoxy primers with varying ranges of durability and protection. The protection and durability come mainly from the film thickness that you apply to the car body, based on the solids content of the primer. The DPLF from PPG is around .5 mil per coat dry film. You would need 8 to 10 coats to get even moderate protection from exposure to moisture and weather. And this product has NO lead which lessens the overall durability. It is also pourous and will absorb moisture with long term exposure to the elements.

    PPG and Sherwin Willams both have "other" epoxy primers with more solids content that will leave a film thickness of 1.5 to 4 mils per coat dry film (you would need to apply 3 to 4 coats), but they are still primers and will not last long term when exposed to the weather and moisture.

    There are industrial epoxy primers with extremely high solids that have more protection (bridge, ship, construction primers).

    The "I'll clearcoat the primer for UV protection" theory is flawed because the UV screener addatives have a short term "life span" in the product and DO NOT last more than 6 to 12 months (as they deteriorate). Clearcoat lets light pass thru it which breaks down what ever is under it. It does give more protection than just primer, but it increases the cost and time to do the job. A good 2 part single stage paint with some good solids/pigments is still the most economical choice--cost versus protection.

    Do the "weight test". Pick up a gallon of white paint-- a gallon of red Paint-- a gallon of black paint, and see which is the heaviest (usually the white-titanium dioxide is a heavy white pigment used in paint and primer). The heavier the product the more solids and probably more protection. The same applies to primers. Pick up a gallon of different primers and compare the weight. The heavier primer will have more solids and most likely more protection.

    The idea is, that when you have more material (solids/weight) between the sun and weather--and the metal of the car, it takes longer for the moisture and elements to degrade the coating and affect the metal.

    overspray
     
  24. langy
    Joined: Apr 27, 2006
    Posts: 5,730

    langy
    Member Emeritus

    I have a friend that blasted & Epoxy primered his 50 Ford 15 years ago and it still look's perfect, We then did the filler work and then Epoxy primed again to seal it, Its now just sits in the corner of the workshop waiting for him to get his ass in gear and flat the guidecoat !!!
     
  25. Slide
    Joined: May 11, 2004
    Posts: 3,021

    Slide
    Member

    To add a bit to overspray's comments (which are spot-on):

    Epoxy primer will protect the metal from rust, etc.

    But you still need something to protect the primer from UV and moisture (if it's going to be exposed to such). Clearcoat over the primer will act kinda like "sun tan lotion" in that it will give you more time in the sun before you get burned, but with enough exposure, you'll still get burned.

    If you keep the car indoors except a couple hours on every other weekend, the primer won't get enough UV's to tear it up, but if it stays outside during daylight hours for a couple hours a day a couple days or more each week, then you'll be sanding & re-shooting pretty soon.

    Best scenario would be bare metal + primer sealer + some kind of paint.

    A common misconception is that everything has to go back down to bare metal every time you re-shoot the car. As long as the prep work is done correctly, and you're not having any problems with whatever is already there, and you're using a compatible product over what's on the car, you should be fine to just scuff the surface and remove any contaminants and shoot right over that.
     
  26. mercjoe
    Joined: Aug 17, 2006
    Posts: 1,377

    mercjoe
    Member

    Ok guys, thanks all for your help. I'll be putting black PPG primer (not epoxy) over and see how good it holds. As I said the car wont see the light more than 2 days a week, and never rain. I dont mind about having to sand and retouching once or twice in the next couple of years. I'll then see what to do..., I just want to put the car together and run it. I'll take the most care so the body doesnt ruin a bit.

    Thanks again
    Diego
     
  27. Petejoe
    Joined: Nov 27, 2002
    Posts: 12,438

    Petejoe
    Member
    from Zoar, Ohio

    This one is 6 years old now and I used Zero Rust with an addition of clearcoat to give a semi gloss effect and to fight the sun issues.
    Its finally starting to have some effect on the top.
    You can add a flat clear to do the same if you prefer a flat finish.
    Zero rust will not allow moisture penetration and is ready to be painted over with any aftermarket paint.
    If fact. I am getting ready to wet sand and paint this winter with a shiny color.

    [​IMG]
     
  28. mercjoe
    Joined: Aug 17, 2006
    Posts: 1,377

    mercjoe
    Member

    Is zero rust a kind of primer ?

     
  29. mercjoe
    Joined: Aug 17, 2006
    Posts: 1,377

    mercjoe
    Member

    Ok Overspray, followed your advice.

    I'll be shooting some paint after all. Though I'll give it the primer coat also since there quite a lot of imperfections I wanna hide even its temporarely. I'll be using PPG Deltron D839 primer over the red oxide. Then a PPG single stage (DG line?) flat black paint

    Diego


     
  30. Poopy
    Joined: Dec 18, 2006
    Posts: 28

    Poopy
    Member
    from abbotsford

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