Primer/Sealer/Gloss was RE: <VV> Old rims question.

[James Davis]

Unless you work fast in a climate controlled, shop that is the way to 
go.  Almost all primers, except the urethanes and epoxies are porous.  In 
the typical situation, they absorb enough moisture in 48 hours so that 
paint bubbling is just a matter of time.  Sealers are usually acrylic and I 
would not mix systems.  With nude metal, I shoot it with two thin coats of 
self etching primer, then cover it with a medium coat of urethane 
primer-sealer.  Bondo sticks well and you can take your time. I have gone 
as long four years between an epoxy primer and final coat with no ill 
effects.  If you don't have a Hobby Air respirator system for urethane, 
then use a mask and epoxy primer.  Just don't spray epoxy then the 
temperature is below 60 degrees and wait about a week before the 
Bondo.  Most fillers are porous so seal then as soon as you can.  I use a 
rattle can of clear and sand it off before the final blocking.  That way 
you can take your time and do it in widely separated stages.   "Metal to 
Metal" is the only non porous body filler I know of.  In the DuPont primer 
line, the self-etch is Varaprime, the urethane is Uro, and the epoxy is 
Colar.  Come to think of my Rampside tailgate has been in Colar for almost 
15 years and no rust.
Jim Davis


At 08:15 PM 2/9/2005, Joel Rushworth wrote:
>A couple of guys up here have taken to using a sealer on the car before the
>mud and primer go on.  The idea being that bondo absorbs moisture and they
>want to put a barrier between it and the metal.
>
>Comments?
>
>Regards,
>Joel