10
« on: April 26, 2013, 08:57:12 PM »
I'm not a Rust expert...I never got my NACE certification, but I did have to follow those industry guidelines....I did a year long stint as a coating supervisor at a pipe company that produced various diameter steel pipes for water transmission that were guaranteed to last buried in the ground for 100 years without corrosion....NWPipe.
I ran one of the coating shops. �Since then I've been convinced that physical prepping is far better than anything else. �That can come in the form of scraping, sanding, grinding, blasting, etc.
We used a Graco system with a two part polyurethane that had a paint and a catalyst that were painted onto the steel pipe on two different nozzles....when they met at the point of impact on the pipe they formed a chemical reaction of over 300 degrees.......and it dried fast. �30 minutes later we would do a pull test consisting of a 1" circular dolly glued onto the paint. �Usually it would take well over 1-4000 lbs of pressure to pull the paint from the pipe. �In most cases, the dolly just ripped off of the adhesive that was glued to the paint on the pipe and the paint remained bonded physically to the steel pipe due to the surface prep.
Bottom line....most of us don't have a $25K industrial paint system in our garages. �But most coatings adhere physically not chemically to the metal. �When you prep for paint, there's got to be a rough surface for it to bond to. � I'd rather use spray Rust-Oleum on a properly prepped surface than powder coating (the usual answer) which IMHO is way overrated....its just not that tough and flakes too much. �Just ensure the humidity is below 85%, everything is dry and have at it with what ever paint you have.....
PS....my advice only applies to tinkerers like myself....if anyone ever follows anything I say and loses at a Concours D'Elegance because of their paint, then just remember,,,,,,I told you not to listen to me. � �;D
Show Posts
