andy everett wrote in message ...
This Saturday I will rent a large sand blast set-up and blast 500 lb. of
steel ornamental fence and gate which will be set up outside. I stopped
by a NAPA auto store and bought "Rust Treatment, Destroys Rust". The
stuff is supposed to turn the surface metal black after two coats.
Should I use this stuff or should I just paint on a primer after sand
blasting, is this rust treatment step worth the effort?

My experience with the rust converters is they only give you a black
surface where there is actual rust -- otherwise, nothing happens
except the surface gets etched slightly from the phosphoric acid.
You'd still have to prime and paint (or at least, I did, when I used
this stuff on my boat).

After sand blasting I suspect there will be trace amounts of oil on the
fence from the air compressor. If I spray the gate and fence with an
airless sprayer with some paint thinner will that remove most of the
surface oil, there are too many cracks and crevices to wipe it by hand?

If you use an oil-base primer like Rustoleum rusty metal red primer,
small amounts of oil won't bother it.

Will Rustoleum brand paint and primer sprayed from an airless sprayer
give good results, from this newsgroups it seems that the best paint for
exterior metal is an automotive type finish, though some people have
said they got good results from Rustoleum.

Yes. I did the very rusty fire escape on a building we renovated in
DC about ten years ago, first wire-brushing with a cup brush and angle
grinder, then 2 coats of Rustoleum rusty metal primer and 2 coats of
satin black. It was just starting to show traces of primer color
again when we sold the building last year. No visible rust. I
consider that to be excellent paint performance.

I just finished doing the same thing to the fences and gate around the
new (to us--circa 1885) house we bought here in San Francisco. Heavy
cup brushing, 2 coats of rusty metal primer, and 2 finish coats. A
good portion of the fence looks like it could be original, or at least
old enough to be forge-welded and riveted iron rather than
stick-welded steel. Hopefully, the paint will last as long as the
last job did, but I've been told that the CA formula for Rustoleum is
different, due to the VOC restrictions, so I guess I'll have to wait
and see.

Regards,

Bob

Thank you in advance for any help or suggestions.