Protecting metal prior to priming

[mhorowit]

Faced with a wait of weeks or months from the time I prepare a steel surface and the time I do the priming, I asked my A&P for suggestions; he suggested linseed oil. Clean it off with MEK prior to priming. or Motor oil, cleaned with break cleaner, then MEK. As others have warned, something like lacquer sprayed on puts a barrier between the metal and the primer. MikeH (and now for a power nap)

[Ragwing nut]

Re: Protecting metal prior to priming

Don't use linseed oil, you will never get it all off. Go to your local auto body store and get a wipe on acid wash conversion coating for bare metal prep. It will stabilze the bare metal until you are ready to paint. No tgoing to give a name, cause it will vary depending on who it is from.

Mike

[mhorowit]

Re: Protecting metal prior to priming

Don't use linseed oil, you will never get it all off. Go to your local auto body store and get a wipe on acid wash conversion coating for bare metal prep. It will stabilze the bare metal until you are ready to paint. No tgoing to give a name, cause it will vary depending on who it is from.

Mike

And that coating isn't going to cause an interferance between the metal and the primer? - MikeH

[flyguy]

Re: Protecting metal prior to priming

Mike,
Is the metal completely bare or are there some small pits?
What I'm thinking is the conversion coating stuff that is available if there are any tiny spots of rust left. It is made to go under primer. It will hold up for a long time if you keep liquid water off of it.
DC

[Ragwing nut]

Re: Protecting metal prior to priming

And that coating isn't going to cause an interferance between the metal and the primer? - MikeH

No it actually helps paint adhesion to steel as alodine does for aluminum

Mike

[Ragwing nut]

Re: Protecting metal prior to priming

Mike,
Is the metal completely bare or are there some small pits?
What I'm thinking is the conversion coating stuff that is available if there are any tiny spots of rust left. It is made to go under primer. It will hold up for a long time if you keep liquid water off of it.
DC

Only can be used on bare metal. It will withstand moisture as long as it is not sitting in water.

Mike

[Jim Doody]

Re: Protecting metal prior to priming

Your local NAPA store carries Martin-Senour paint products, #7220 self-etching primer is availible in a spray can. It is a convenient way to protect your project from rusting and can be topcoated with an epoxy primer when ready. Jim

http://www.martinsenour-autopaint.com/ap/tecnique.htm

[flyguy]

Re: Protecting metal prior to priming

Mike,
The conversion coating I am thinking about is specifically made for converting any minor rust that is left after brushing or sanding the loose stuff off. It was originally made by Permatex and then Napa put their label on it and finally several other companies came out with their version. It turns any pits or rust that doesn't come off to a hard black material with a hard glossy overcoating. It isn't made for bare material, but will just turn it blue or gray or black depending on mfgr.
I'm sure it isn't certified for aircraft, but then.....
I think we discussed it before for use on small, non-critical parts. Really nice thing about it--if there are any small crevices that you can't get completely rust free, bingo, problem solved.
DC

[mhorowit]

Re: Protecting metal prior to priming

Don't use linseed oil, you will never get it all off. Go to your local auto body store and get a wipe on acid wash conversion coating for bare metal prep. It will stabilze the bare metal until you are ready to paint. No tgoing to give a name, cause it will vary depending on who it is from.

Mike

Mike - The conversion coating I'm aware of requires there be some rust to convert!. I'f I"m putting this conversion coat over clean metal, I don't see that it's going to do anything for me except form a coating that could interfer with the primer. Your thoughts? - MikeH

[Ragwing nut]

Re: Protecting metal prior to priming

Mike - The conversion coating I'm aware of requires there be some rust to convert!. I'f I"m putting this conversion coat over clean metal, I don't see that it's going to do anything for me except form a coating that could interfer with the primer. Your thoughts? - MikeH

Not the same stuff. Here is a link to Blue Lightning. It will hold bare metal from rusting they say up to a year. I have used it on a '68 Camaro that has been in bare metal for 3 years and has no rust where treated.http://blulightning.com/