On Mon, 7 Feb 1994, Scott Fisher wrote:
> I'm pretty sure that Hammerite does make a crinkle-finish paint.
> If not, I discovered how to do crinkle-finish without the special
> paint, as part of my continuing study on How To Ruin Paint.
>
Maybe they do, but I have not seen Hammerite wrinkle finish here yet.
> > > I put the hammertone paint over bare metal. By bare, I
>
> If you did use Hammerite brand paint, you're basically stuck with
> it. That stuff is supposed to be virtually indestructible -- rust
I think I (WRG) threw a monkey wrench into the works. I mentioned
Hammerite as an example of hammertone paint. The original poster never
mentioned any brand, and I don't in fact think he/she used hammertone
paint, much less Hammerite.
> Ah, but in the hands of a Trained Paint-Ruining Master, even ordinary
> primer can turn smooth-finish semi-gloss black into crinkle finish! Just
> take a look at the front cross-member of my MGB sometime! :-)
>
Hmmm... Let me just say this about that. As part of the exceptional march
of technology, paints are getting so technically advanced that some paints
are not compatible with themselves unless conditions are dead nuts
perfect. In general, one must follow directions compulsively. It is the
painter's equivalent of RTFM.
I am not just talking about the "paint systems" that say for professional
use only. For example, rustoleum makes a lovely semi-gloss black in spray
bombs, which is just the right luster for under bonnet parts. But the
package says (now this is from memory, so bear with me if I don't have it
quite right) that, should you wish to apply a second coat, you should
either put it on within 30 min, or wait a couple of days. And by Jove, if
you recoat it in an hour and a half, it will wrinkle up and lift and do
every mean, nasty, ugly thing you can think of, forcing you to remove
everything and start over. In fact, if the weather is cooler than package
specs, it takes longer than 2 days before it can be recoated. Rustoleum
has also made a primer that is only marginally compatible with Rustoleum
or anybody else's finish paint (zinc chromate for lightly rusted metal).
It dries slower and works much worse than their primer for heavily rusted
metal (red). I shall never know of what they were thinking.
Many modern acrylic enamels are incompatible with themselves ("recoat
sensitive"). In other words, paint something with acrylic enamel. Decide
on another coat for more protection. Presto: wrinkles, cursing. The cure
is to recoat early, or not at all, or to risk life and limb by using
cyanoacrylate hardener.
Take home messages:
Avoid rustoleum yellow zinc-chromate primer; it will give you and your
paint hives. There is no right way to use this stuff.
Embrace rustoleum red rusty metal primer. It is great stuff, if you let
it dry a *long* time. Either a) use rustoleum finishes on it, per
directions, or b) let it dry several days or weeks, then coat with any
enamel paint. But not lacquer.
Never apply lacquer over fresh enamel, it will lift. The exception is
some types of catalyzed enamel ("epoxy") primers, over which lacquer can
be painted, if done according to directions. If SF1 applied lacquer type
primer over fresh enamel, the basic incompatibility is why it lifted.
Avoid DuP*** etch-type primer (the mustard colored stuff) like the plague.
This is interesting stuff, in the same sense that a good case of the flu
is interesting. Bondo won't stick to it. I painted a nonchip coating
over it, and the primer dissolved turning the whole bottom of the car to
slime. I am not real sure paint will stick to to the etch primer. I
expect primer to sit there and do its job, I don't expect it to erupt in a
massive case of zits when the going gets a little tough. OK, I am
overstating the case. Some people swear by this stuff, but all I ever
have been able to do is swear at it. As always, YMMV.
Hammerite may be great; it needs no primer. There is a companion product
called Smoothrite, but I don't know if it's imported here yet. I have
heard it is so hard that it is prone to chip when used on undercarriages.
Ditzler/PPG DP40 or DP50 epoxy primers are really nifty. Waterproof, hard
as nails, no sand if you recoat soon enough, take just about any finish
coat. You can apply bondo over the primer, in fact it is recommended that
you do this. Can be thinned and used as no sand sealer, just before
finish paint, decreasing likelihood of lifting. Costs like the devil, but
worth every penny. Wear a good activated charcoal mask with fresh
cartridges, keep windows open.
Lacquer type primer surfacers are fine for building up the surface after
epoxy priming, but I wouldn't use them as the only primer over metal.
As you use the above info, keep in mind it is worth about what you paid
for it.
Ray Gibbons
Gibbons's rule of auto painting: Sand with 360 wet and dry, epoxy prime,
sand with 400, apply primer surfacer and guide coat, sand with 500, apply
catalyzed enamel, color sand with 1200, buff, wax, all with painstaking
care and according to directions. The paint will lift in 6 months. But
that wee place where you got finish paint overspray on well-waxed chrome
will be there until you die.
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