Question regarding steel posts

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I'm looking to fab up a cantilever steel gate for access to my backyard.  While strolling through downtown today, I noticed that many fence and railing posts were simply set in concrete.  My question is do I need to treat the steel with anything before I set the post in concrete?  I just can see why the steel post wouldn't rust from the moisture in the cement.  I can paint it before setting it, but what about the interior of the post.  Seems like the steel needs to be dipped into some type of inhibitant.  Not looking to use galvanized steel.  Any help is certainly appreciated!
Reply:A post in concrete won't rust - there's no oxygen to promote the rusting process.  Ever seen rebar on a construction site, such as a bridge deck?  It's usually rusty when it's put in the form and concrete is poured around it.
Reply:Ahhh...good point.  I did however, saw some posts that had rust at the very bottom...right where the steel came out from the concrete.  I assume this is from moisture getting inside the post (condensation or poor welds) and pooling atop the concrete inside the post?  Or possibly vibrations cause the paint to rub off at that location?  Just don't want to make the same mistakes that obviously others have.  Thanks for your reply.  As soon as I read "rebar" I was, "Doh!" LOL.
Reply:One guarantee about using steel - it's gonna rust eventually.  If you can cap the top, that will help, or even better, fill the post with concrete.  At the base, taper the concrete so water will run away from the post.
Reply:You could use a galvanized post and just cold gal the weld areas before painting.Or you could get your finished post hot dipped.sorry didnt read the end of your post.
Reply:a steel post WILL rust in concrete over time.  Most of the time it is from the inside out.  I have replaced far too many over the years that did that very thing. See if you can find a couple gallons of cold galvanizing paint, or good epoxy paint.  Put it in a bucket and dip the post in the depth that you will have them in the concrete.  That will give you some protection inside and out.I'm a Lover, Fighter, Wild horse Rider, and a pretty good welding man......
Reply:On gate post and other critical weight bearing post I pour a footer, and mount to a footer.  Several advantages to this method aside from rust control... I did a thread on my cantilever gate about a year ago.  "my first cantilever gate" I think it was titled.
Reply:Originally Posted by crashmcwhly...While strolling through downtown today, I noticed that many fence and railing posts were simply set in concrete....
Reply:As with wood posts set in concrete make sure the concrete is sloped on the top surface around the steel pipe to prevent moisture puddling at the pipe.  The climate has much to do with corrosion rates.  Below 40 F corrosion rates are low.  Combine that with a dry climate and it will last a lifetime.  I was amazed to read that arctic tundra conditions are almost as good as traditional desert climate.
Reply:This is probably a dumb thing to do and I willingly admit it, but...I built a fence out of square hollow sections in concrete about 10 years ago. The posts were sealed on the bottom.I put the posts in, concreted around them, and then poured a couple of litres of sump oil down each one.Scott
Reply:Originally Posted by scott brunsdonThis is probably a dumb thing to do and I willingly admit it, but...I built a fence out of square hollow sections in concrete about 10 years ago. The posts were sealed on the bottom.I put the posts in, concreted around them, and then poured a couple of litres of sump oil down each one.Scott
Reply:I haven't been around this stuff in years.I seem to recall some code things about exposed metal coming into contact with a wet pour.  Concrete is corrosive.Also I remember some things about whether the mix was waterproof.  I think concrete is considered "waterproof" at maybe 6sacks/yard and up.  Might be up around 7 sacks.Also used to see a lot of the coated rebar.  I'm not sure whether it was coated to prevent the lime from corroding it, or because of water contact.It's been years and years, and I'm probably way off the markSomebody here must know something about it"Any day above ground is a good day"http://www.farmersamm.com/
Reply:It was a shared fence on a house I rented out. Thinking back, that fence would have gone up in the early 90s. Last year the neighbours did a renovation and the builder had to pull the fence down. I happened to be there the day he was doing it and heard him cursing the ******** who filled the posts up with oil.'Who me? I didn't do it, honest.'Of course, I did make the observation that the oil seemed to stop them rusting and that whoever did it must have been pretty clever.Last edited by scott brunsdon; 05-12-2009 at 10:13 PM.
Reply:Something they used to do with barges was put old oil in the bilges then while in dry dock sink them by opening the seacocks.  The oil would float on top of the bilge water and coat the inside of the barge.  afterward they would pump out the bilge water leaving the bilge coated in oil.  Not really a "green" thing to do but in times past....   Tubular airframes were also filled with linseed oil and drained with the same idea in mind.
Reply:Originally Posted by scott brunsdonThis is probably a dumb thing to do and I willingly admit it, but...I built a fence out of square hollow sections in concrete about 10 years ago. The posts were sealed on the bottom.I put the posts in, concreted around them, and then poured a couple of litres of sump oil down each one.Scott