Spray paint question...

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May 26, 2003 | 11:52 AM

Red69

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Racer

Joined: Dec 2002

Posts: 306

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From: N. Charleston SC

Spray paint question...

We all use it because it convenient.... :thumbs:

... so, what exactly does "self etching primer" do over other paints?

May 26, 2003 | 11:54 AM

79VetteMike

Melting Slicks

Joined: Jan 2003

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From: OKC Oklahoma

Re: Spray paint question... (Red69)

i think it help adhere to the paint and underlying material better.

May 26, 2003 | 11:57 AM

Greg

Just another Corvette guy

Joined: Feb 1999

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From: Palm Springs, CA.

Re: Spray paint question... (79VetteMike)

C'mon John, sill "tagging" at your age? Why don't you just throw some eggs at those annoying neighbors! :lol:

May 26, 2003 | 10:26 PM

CF6873

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From: Lancaster PA

Re: Spray paint question... (Red69)

Self etching primer typically contains an acid which will somewhat etch bare metal contributing to adhesion. It usually can be used over paint but it may take a bit longer to dry since the acid will have to evaporate instead of chemically reacting with metal. Craig

May 27, 2003 | 02:04 PM

lars

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From: At my Bar drinking and wrenching in Lafayette Colorado

Re: Spray paint question... (Red69)

As CF correctly noted above, the self-etching primers etch themselves into bare metal. They are used to create an adhesion base on bare metal surfaces and to seal bare metal. Typically, etch primer is used to cover small bare areas exposed during the final wet sanding process just prior to application of the basecoat, since basecoat will not "stick" to bare metal. Etch primer can also be used as an adhesion base on bare metal prior to application of filler materials. Etch primer is not a fill primer, so it cannot be used for "blocking" out a car. It's more of a sealer and base.

May 27, 2003 | 02:15 PM

75Rag

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From: Behind the wheel of a large automobile

Re: Spray paint question... (lars)

Would the fact that I didn't use "self etching primer" be the reason the paint on my valve covers didn't take in some areas?

May 27, 2003 | 05:06 PM

lars

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From: At my Bar drinking and wrenching in Lafayette Colorado

Re: Spray paint question... (75Rag)

Engine parts and valve covers are usually best prepped by wiping them down with a good grease remover and then shooting a coat of epoxy primer (such as PPG's "DP"-series epoxies). The epoxies are better suited to higher temperatures, and they provide a sealed barrier impervious to moisture, oil and grease. Topcoat the epoxy with a good urethane paint, such as PPG's Delstar (available in Chevy engine orange). The etch primers are thinner than the epoxy, and they are not a sealer.