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Discussion Starter #1
i have got a few new reproduction parts such as a hood and fender that came with the regular black coating on it. I assume this is what they call e-coat right? What type of primer should i put on these parts. I will be painting a few bare metal parts with 2k etching primer then 2k acrylic urethane primer both made by transtar. Can i use the same process on the coated repo parts or should i do something different?
Also is this transtar stuff any good?
thanks
 

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Troll Hunter
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You can probably just shoot your color coat on the e-coat, after a light scuffing. Since you are shooting other parts you should be able to use the primer/sealer you are using on them.
 

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Yes Transtar is a good product.

You have three options on your e-coated panels.

Best option:
1)Clean with a wax and grease remover than with a GRAY scuff pad sand the panels and spray a wet coat of epoxy. (No acid etch) Than paint over the epoxy.
This will be the MOST durable finish for the long run.

2nd best:
2) Scuff with 180-320 and shoot a coat of your 2k primer than sand and paint.

Last choice:
3) Yes you could scuff and shoot paint over the e-coat but how strong this will be long term depends on a lot of factors out of your control. newer car parts are done this way every day in shops but your doing I assu-me a classic so best to pull out all stops.
 

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BarryK said:
Yes Transtar is a good product.

You have three options on your e-coated panels.

Best option:
1)Clean with a wax and grease remover than with a GRAY scuff pad sand the panels and spray a wet coat of epoxy. (No acid etch) Than paint over the epoxy.
This will be the MOST durable finish for the long run.
Why would you clean with a grease/wax remover first?? That should be the last step prior to shooting.. Scuff with gray scotch bright first then clean with grease/wax remover then shoot your primer..:sweat:
 

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Brian Martin,Freelance adviser
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You should ALWAYS clean first as well. If you don't, you will sand the contaminants INTO the substrate!

Wax and grease remover is CHEAP. Like an old painter I worked with as an aprentice used to say (barking like a drill sargent) "You can never get a car too clean ".

One thing that hasn't been mentioned, is this REALLY "E" coat? These are reproduction parts, we don't know what quality they are, that black primer may be junk for all we know.

At the very least, do a solvent test with a rag wet with lacquer thinner. Rub it well on this primer and see if it softens or transfers to the rag. If this is the case, and it off and apply a good epoxy primer.
 

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Shop Owner And Troll Hunter
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I've never had any luck painting over e coat, I remove it on everything.

Troy

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If you don't make mistakes. your not doing anything.

69 SS/RS full custom Camaro 98 ISCA Grand Champion
69 SS/RS BB Camaro wifes driver
66 Elcamino 350/all dz parts,ac,windows,loaded,my driver
69 SS Chevelle BB conv.fresh frame off
26 T sedan street rod
 

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Brian Martin,Freelance adviser
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Troy, "E" coat is zinc rich and a very good base for your following undercoats. You don't have to even grind it off when welding on it, you can strike an arc with a mig right on it!
 

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Shop Owner And Troll Hunter
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Yeh I know, but like I said I never had any luck leaving it on.

A lot of parts are dipped and hung up, that lets the e coat just run of, which leaves an uneven thickness that sometimes shows through the finished paint job. So I just take it off and start out smooth.

Troy

__________________
If you don't make mistakes. your not doing anything.

69 SS/RS full custom Camaro 98 ISCA Grand Champion
69 SS/RS BB Camaro wifes driver
66 Elcamino 350/all dz parts,ac,windows,loaded,my driver
69 SS Chevelle BB conv.fresh frame off
26 T sedan street rod
 

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The idea of e-coat is apply in an exact mil for maximum corrosion and adhesion .
This is why auto manufacturers want you to scuff with a gray pad so you take very little off. Their real preference is you wash it with wax and grease remover and don't sand it and use a sealer or primer that sticks to e-coat without sanding.

In past where people have had bad experiences with e-coat has been where they sand with 180 and take a lot of the e-coat off than use lacquer primer over the rest. Since those days are gone
it should not be a concern.
 

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Ferguson Coachbuilding
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I know where Troy is coming from. I too used to have trouble with it, but that was back when all we used was lacquer primer or Velva-Seal before going to paint. I now just scuff it with a scotchbrite pad and go straight to sealer or epoxy, depending on the situation. I haven't had any blow off since back in the days of using lacquer. Back then, I did just as Troy does and sanded every bit of it off! We do things a little differently than most shops when edging panels. I scuff the entire surface fo new parts with a scotchbrite pad, apply sealer or epoxy to both inner and outer surfaces, allow proper flash and apply three coats of color. The parts are then hung on the car and the base is sanded with 600 grit wet along with the rest of the repair and blend areas before final color is sprayed. This cuts down on booth time for the final paint process and also tells us when the parts are hung is the color is a good match. Even though the clear isn't on the outter surface, you can still tell how well the color will blend. If it's off by very much, I will adjust it before heading into the booth to paint the car.

Randy
 

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Shop Owner And Troll Hunter
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I've never had adhesion problems. Mostly uneven mill thickness in the ecoat, like a sanded out run that shows in the gloss finish.
Some panels are alright , some arn't. If I see that it is fairly even after cutting it down I go with that.

Troy

__________________
If you don't make mistakes. your not doing anything.

69 SS/RS full custom Camaro 98 ISCA Grand Champion
69 SS/RS BB Camaro wifes driver
66 Elcamino 350/all dz parts,ac,windows,loaded,my driver
69 SS Chevelle BB conv.fresh frame off
26 T sedan street rod
 

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Discussion Starter #12
thank you all for the information again.
i am just assuming this stuff is e-coat(yes i know i should not assume anything). It is a hood and fender on a 66 mustang that were on the car when i bought it. The fender is good and smooth, the hood on the other hand started to get a lot of surface rust on it before i got it in the garage.
The reason i asked about the 2k self etching primer by transtar (part # 6111) is because on their website and catalog it says it
"performs as an excellent tie coat for any top coat system when applied over unsanded e-coat panels"
the hood i realize i will have to sand on it to remove the surface rust, but the fender is still real clean and smooth.
 

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Ferguson Coachbuilding
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That's a different ball game! Since it sounds as if it's set out for a period of time, I would strongly suggest sanding it to bare and coating with epoxy.

Randy
 

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Discussion Starter #14
oh yea, the hood i know i will have to sand to bare metal. The fender is the one i was concerned about since it is rust free.
 

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Ferguson Coachbuilding
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It may look rust free, and possibly is, but why take chances when you can have it bare in about three minutes????????
How much would it cost to repaint in six months when it looks like spider veins popping up everywhere on it??????????????????
Shortcuts aren't always a means of saving time!!!!!!!!!!!!!

Randy
 

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The first reason I always remove "e-coat" is THE COATING WAS APPLIED TO TOALLY SLICK SMOOTH STEEL. It is just a skin on the metal and has "0" impact resistance for stones, parking lot dings, etc. Any coating on steel has to have some "scratch" to hold well.

The second reason to remove it (definitely on repo-taiwan mustang parts) is at best, it is probably crappy cheap e-coat and possibly "transport coat" .

My test is is to use Jasper premium epoxy paint stripper ($8qt. Lowes, great stuff, goes dry, no mess, on most finishes*).

Hood and P fender: Jasper literally popped the "e-coat" off in sheets, cleaned up with my shop vac = ? transport primer.

D fender: Jasper just layed there wet*, no reaction, BUT it wiped off very easy to the smooth steel with steel wool = ? good e-coat.

Quarters, valance, etc., based on the above results, sanded to bare steel with 80 grit for epoxy

IF the Jasper stays wet AND it is an area that gets "0" abuse (inside quarters, back of valance?) then leave it maybe......

Last note: your new hood is going to rust from the inside out along the front inner lip due to heat/moisture/transport primer.

Stand it on its nose and pour and spray epoxy/por15/rustoleum/whatever till all the support and panel joint is totally coated

"et caveat emptor" = "and the buyer beware "

Steve
 
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