[Spits] Primer Vs Etch Primer?

[Doug Braun]

Etch primer is meant for bare metal.  It is supposed
to etch the metal a little bit so that the primer will
have a rougher surface to stick to.  It is not
generally meant to do anything for rust.

I have tried some of the Dupli-Color self-etching
primer, but it has a lot of filler, so it is not very
hard or strong.  I tried painting some chassis parts
with it, followed by black epoxy enamel, and I found
they chipped very easily.

BTW, I once bought some Rust-Oleum "Rust Reformer"
spray paint, which is supposed to "instantly convert
rust to a protected, paintable surface!" I sprayed
some on a rusty piece of metal, an later I could
scrape it off and find the rust still underneath.  It
did not seem to behave any different than normal spray
paint.

I have also seen those milky-looking water-based
products that neutralize the rust and turn it black. 
That's fine, but afterwards you have a latex-based
primer on your car.  Is that really a good idea?

I am pretty cynical about any product that is supposed
to be painted over rust and make it effectively go
away.  I am working on restoring a '31 Ford, and I
sandblasted and soda-blasted the body and chassis to
bare metal and used 2-part epoxy primer.  But to do
this, I had to take the car totally apart, and it's
taken about 2 years so far.

For my Spitfire, when I notice some of the original
paint peeling off of the chassis,  I take out my
trusty can of Hammerite and touch it up...

Doug Braun
'72 Spit

--- Nick Moseley <nmoseley at dccnet.com> wrote:

> My question is: what is the difference between
> "regular" primer, and "etch"
> primer? I saw a show recently where they sprayed on
> etch primer in the
> expectation that it would neutralize surface rust,
> and leave a primed
> surface. It was an Eastwood product, but I see Etch
> primer for sale at my
> FLAPS.