opinions on rust conversion paint????

[LutzTD]

I have some I-beams that are going to be sitting for a while. I got them used and they have a year or two worth of surface rust. Would it be better to wire brush them, primer and paint them or use a rust conversion paint. I have heard the new conversion paints are pretty darn good.

thanx

 

[djjsr]

I'd use POR-15.

 

[OldmanB]

I'd use POR-15.

Good stuff, but don't plan on doing any welding after without much grinding,the fumes are a killer on the lungs.
Brian

 

[tcianci]

POR 15 for sure. I got an I beam about 12 years ago to use with a trolley for my engine hoist. It was surface rusted. I wire brushed it and then did the cleaner, prep and POR 15 topcoat. It is as nice today as the day I painted it, shiny black. Follow their instructions and you won't be disapointed.

 

[Old Moparz]

Another product to consider is made by PM Industries called Mastercoat. I've used this on many car parts & the rusty steel lally columns in my basement. A friend turned me onto it about 20 years ago & said he likes it better than POR 15.

http://www.masterseriescoatings.com/index/

I bought high temperature coating from them but have not tried it yet. Hope to this winter & will see if it's any good.

 

[Kevin54]

Wire brush, use some Naval Jelly, clean real well, then paint.

I'm not as huge fan of Por-15, Chassis Saver, or any other that states "rust encapsulating". All that type of paint does is seal the existing paint from air and keeps it from rusting more, or so they say. The rust is still on the base material. If thick enough rust, it can still chip off and then you are left with an exposed portion of metal.''

If you want it to look good, clean it so it is as smooth as possible. Use something that cleans rust. If anything, spend some money on a few bottles of CLR to get it removed, or if close to someone that does sandblasting, hit them up.

You will be much happier if done correctly instead of taking a shortcut to cover the rust.

Just my two pennies on that though. Take it for what it's worth.

 

[fflintstone]

I like POR-15 and other encapsulating paints.
Conversion paints are actually different and use a chemical reaction to “convert” rust to a inert state.

Both work well if applied properly. Neither type is a be all end all for rust. Top coat is essential for POR-15 it will photo degrade otherwise. Conversion paints need topcoat as well.

IMO either will work fine for structural steel.

They are also good at slowing rust out on a car that is already starting to go, but need to remain in service till time and funds allow proper restoration or retirement.

 

[Gary S]

I have never tried POR-15, but I have had some good results from a product by DURO, called Extend.
I tried it on some auto body rust about 25 years ago, and it worked. The sheet metal I treated 25 years ago has survived because it neutralized the rust.
I bought another bottle of it a couple of years ago to use on another project, but with only two years time, it would be too soon to know if the current product is as good as yesteryear's product was.

 

[LutzTD]

Wire brush, use some Naval Jelly, clean real well, then paint.

I'm not as huge fan of Por-15, Chassis Saver, or any other that states "rust encapsulating". All that type of paint does is seal the existing paint from air and keeps it from rusting more, or so they say. The rust is still on the base material. If thick enough rust, it can still chip off and then you are left with an exposed portion of metal.''

If you want it to look good, clean it so it is as smooth as possible. Use something that cleans rust. If anything, spend some money on a few bottles of CLR to get it removed, or if close to someone that does sandblasting, hit them up.

You will be much happier if done correctly instead of taking a shortcut to cover the rust.

Just my two pennies on that though. Take it for what it's worth.

Ive never tried CLR on big stuff, the beams are 20 feet long. They have been sitting outside for quite a while,and they are covered in a thick surface rust. I did not see any issues of more than surface rust, no delamination or anything, but the ends are buried in sand. I just want to understand what I will need to do to make these usable. My first thought was to wire brush off the rust and paint, but if I could just paint maybe they would be more worth while.....

 

[Angelfire]

I would remove the rust and then paint well. At least that way, you know exactly what you've got. I tried POR-15 and will never touch the stuff again. Peeled off in sheets after following all the directions to a T. I find in the 4 wheeling world, about half the folks love it, and about half hate it. YMMV of course.