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OK what is the differance between Epoxy primer and Self etching primer? Which should I use for the Cowl repaire while I have it open? It is the Dynacorn Cowl I just bought for 423 bucks at Mustangs unlimitted.

Auto Zone seems to only have the self etching primer. Is this what I use?

And Seem sealer where do I get that? Does Auto zone carry that too?

thanks.
 

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OK what is the differance between Epoxy primer and Self etching primer? Which should I use for the Cowl repaire while I have it open? It is the Dynacorn Cowl I just bought for 423 bucks at Mustangs unlimitted.

Auto Zone seems to only have the self etching primer. Is this what I use?

And Seem sealer where do I get that? Does Auto zone carry that too?

thanks.
Hi,
Does your cowl have an "E" coat? If so, wipe it clean using a paint cleaner. You want to use a cleaner that does not leave any residue. Autobody supply stores sell a metal cleaner that's just for this purpose. Then shoot it with an epoxy primer. Some folks will remove the "E" coat, but, I don't think it's really necessary, as long as, it's intact.
Good Luck!
 

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You need to scuff black primer they have on it and just use an epoxy primer over it. The autobody supply store should have the sealer you need. Seal AFTER you prime.
 

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Use wax and grease remover for cleaning before painting. You can get it at the paint supply store too.
 

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40 year body tech

E stands for epoxy scuff panels with red scuff pads cleans with a good chem. Cleaner apply 2 med.coats of ppg epoxy primer. It comes in red,gray,white,black and white.so your colors are cover.be sure to use weld thur. Prime if you are welding.try to find flo grade seam sealer for inner seams 3m brand work the best
 

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Self etching primer has acid in it to make it adhere to the metal. Epoxy is a better primer. If you clean your metal and scuff it good the epoxy will hold very well. I don't know if you can buy epoxy in rattle cans though.

The only bad thing that I know about the epoxy is that sunlight will deteriorate it.

Check this site out.

www.hotrodders.com
 

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Autozone has seam sealer, but you have to ask for it, or at least I did. They keep it behind the counter, but all they have is the tube (like caulk). I had to order the brushable from Eastwood.
 

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Autozone has seam sealer, but you have to ask for it, or at least I did. They keep it behind the counter, but all they have is the tube (like caulk). I had to order the brushable from Eastwood.
ditto on the Eastwood part... that and some POR-15, my cowl is untouchable!! hahaha
 

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First thing is forget AutoZone for paint supplies. Unless you are way back in the sticks, there will be a autobody/paint supply store somewhere close. These people can be your best friend. Other than that, all good advice already posted.
 

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If you use Por 15 on new metal, make damn sure that your metal is roughed up with COARSE abrasive-like 40 grit! That is what their original instructions said! That stuff will peel if it is NOT thoroughly roughed up. It wasn't meant to be put on new metal. Epoxy primer and a coat of same band urethane color coat is best. Make sure that your seams around the high hats are sealed-after the primer as mentioned.
Yeah, Auto Zone, Advance are not paint stores. Go to an automotive paint store.
 

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The "E" in e-coat is for electrostatic, not epoxy. It's the method of application.

Self-etching primer and epoxy primer are not an either/or thing. They are designed to work together. Typically self etching primer is applied first to bare metal. The acid bonds to the metal and neutralizes any microscopic rust. Epoxy is applied over the self etching to then seal and prepare for subsequent layers.

You will get different answers from different people but I remove the e-coat and start from scratch. I do not trust an expensive, time consuming paint job to assembly line primer. A paint job is only as good as it's base coat.

Rattle can paint will never be as durable as spray gun paint. It is air drying as opposed to catalyst hardening.

Pick your topcoat first. Then sticking to the same brand work their system back to the metal. Using the primers suggested by the top coat manufacturer ensures all the paint layers will play well together, and give you your best shot at a lasting paint job.
 

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Self-etching primer and epoxy primer are not an either/or thing. They are designed to work together. Typically self etching primer is applied first to bare metal. The acid bonds to the metal and neutralizes any microscopic rust. Epoxy is applied over the self etching to then seal and prepare for subsequent layers.
I'm not saying that the way you do your primer won't work but there are a lot of professional people who put epoxy primer over bare metal.

This if from a paint company.

http://www.southernpolyurethanes.com/perfect%20paint.htm
Bare metal is always best cleaned with #700-1 Waterborne Wax and Grease Remover then let it set 30-60 minutes before applying the epoxy!
Perfect Paint Job
All bare metals and aluminum should have 80 grit DA scratches.
 

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I guess I could have said that differently. My response was to your "epoxy is a better primer" statement. It's not better, it's designed for a different purpose. What I meant was it's not a case of use epoxy or use etch primer. They're different items meant to work together. Not in place of one another.

Of course a lot of professional people skip the etch primer. They are far more concerned with total cost than someone working on their own prized possession. Personally I think etching primer is a valuable first step in getting the best possible paint job. Can you skip it, sure. But I wouldn't.
 

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Etch primers are for using on new, smooth, non sanded metals. It is designed to save on production times by not having to sand the new metal for the primer to "bite" in to the metal. Once you have sanded new metal, you have etched it. On new panels, I sand the majority of the EDP off and apply two coats of SPI epoxy then some primer. After a day or two apply a few good topcoats of your favorite topcoat before welding on the top of the cowl.
A good place for etch primer would be somewhere like new floor pan sections that come in raw metal with no EDP. You could use etch primer on these areas without having to sand them down first. I opted out to just sand mine down with 80 grit on a DA sander then I epoxy primed them. BUT, you have to make sure you get EVERY nook and cranny or those areas can flake off.
After 15 years in the bodyshop business, I learned a few tricks.
 

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+1 on epoxy primer over prep'd metal. I like to use a random orbital sander with 40 grit to rough up new metal. Never had an issue with the epoxy peeling off.
 

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Etch primers are for using on new, smooth, non sanded metals. It is designed to save on production times by not having to sand the new metal for the primer to "bite" in to the metal. Once you have sanded new metal, you have etched it. On new panels, I sand the majority of the EDP off and apply two coats of SPI epoxy then some primer. After a day or two apply a few good topcoats of your favorite topcoat before welding on the top of the cowl.
A good place for etch primer would be somewhere like new floor pan sections that come in raw metal with no EDP. You could use etch primer on these areas without having to sand them down first. I opted out to just sand mine down with 80 grit on a DA sander then I epoxy primed them. BUT, you have to make sure you get EVERY nook and cranny or those areas can flake off.
After 15 years in the bodyshop business, I learned a few tricks.
From PPG's Tech Sheet.
DX1791 may be applied over:
· Properly cleaned and sanded Steel
· Properly cleaned and sanded Galvanized Metal
· Properly cleaned and sanded Aluminum
 

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read the P-sheet from PPG's epoxy primer. clean and sanded metal is an acceptable substrate as long as you spray the needed film build. i always spray two reduced coats.

no need for an etch primer.
It says "acceptable", not the only or the best way.

https://buyat.ppg.com/refinishProductCatalog/ViewProduct.aspx?ProductID=ebd75e7f-7489-4334-a387-73f8653e2a34

be sure to read the p-sheet of whatever product you use. the above epoxy specifically states to NOT top coat over some of their etch primers.
That p-sheet also states it can be applied over DP1791, their most commonly used etch primer. Obviously you would want the correct etch primer.

PPG's tech sheet also states: "Chemical treatment or the use of a conversion coating will enhance the adhesion and performance of the finished system."

When I started my project I knew the amount of work that went into painting a car. I wanted the absolute best shot at having a successful outcome. I had a lengthy email conversation with a tech at PPG. Because of it's obvious etching properties and it's ability to neutralize microscopic corrosion, he suggested starting with DX1791 etch primer. So that's what I am doing. You certainly can skip that step and many, if not most do. But I want the odds tilted as much as possible in my favor.
 
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