Your question is far too vague, but painting steel is not rocket science.
However, here are some rules. Don't paint over mill
scale or rust. If the steel has not been shot blasted, it still has mill scale
on it and that will lift on its own, so it must be
removed. Wire brushing and grinding is slow and ineffective for this. Sand and
shot blasting to white metal is much better.
Purpose rusting helps to lift the mill scale and makes blasting faster. If rust
exists and cannot be removed. The use of muratic
acid works well. If that cannot be used, then it can be converted with
converters. In the case of chemical use, the chemicals need
to be washed away with water and neutralized with a soda and then washed again.
After all of these processes, you have a short
window of time to get the first coat of etching primer applied before corrosion
sets in. Depending on prevailing conditions, that
window is between 20 minutes and 2 hours. Whatever paint system you elect to
use, you must follow the manufacturer's directions
verbatim. Do not take short cuts. The first paint applied is critical to the
paint scheme being applied and all the other ones
which may occur later on. You probably think I'm really anal about this and well
over the top. I am not. Take short cuts and you
will learn the hard way. Many times these rules are not followed, but only in
the cases where the failure will occur on some one
else's dime or ignorance is present..
Confirmed: sanding these parts 24 hours after spraying 2nd coat and the paint
is not dry. Gummed up the sand paper.
Boy, does this Rustoleum paint dry slowly... It says 48 hours, but at this
rate it looks like it will be longer.
Is Krylon a better choice? Or...?
Rustoleum is good paint. There are other heavy-duty enamels, from the
majors, but most straight alkyds are going to take a long time to dry hard.
That's just enamel. Rustoleum probably is slower to dry than most. In many
applications, they don't use a second coat. It's better to use a good
primer, and then the top coat will lay on a lot thicker than each coat used
without primer. Get a compatible primer made for use with the enamel.
There are a lot of industrial-type paint systems out there today, including
several polyurethane systems that are tough and that produce a nice finish.
Probably the toughest is two-part polyurethane, which comes in brushable
versions. Don't touch the spray-coat versions unless you study it well. It's
highly toxic and you can't protect yourself with just a respirator. But the
brush-on is safe.
I like plain, old-fashioned enamel. But I use it with primer.
On Tue, 1 Sep 2009 19:23:25 -0700, Ed Huntress wrote
It's odd: same series Rustoleum paint, one flat white, one gloss
The flat white dries very quickly. I've applied additional coats as quickly
as 1, 3, 4, 6 hours without sanding, with no evidence of wrinkling.
The gloss orange, on the other hand, is 72 hours and counting, with no
evidence of complete drying. It is still possible to dig in a thumbnail and
see its impression. (This is outdoors in 80 degrees with pretty low
I think I'll strip and try Krylon, or an automotive paint supplier's enamel
in a Harbor Freight DIY spray can. The Rustoleum is going back to Orchard
Yet another thing I've done, on electrical enclosures that had to look
real spiffy, is to buy a case of beer for the guy at the local body
shop and have him paint it for me. No muss, no fuss, no respirator,
and a damned good job.
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