Are there any inexpensive rust inhibitors?

[belfert]

Are there any inexpensive rust inhibitors?  Rust Bullet looks like a good product, but I probably need a gallon at a cost of $150.  I see McMaster-Carr has a few options, but they cover a huge price range from $30 a gallon to $100 a gallon and I have no idea if they work as well as more expensive products.

I'm also considering sand blasting the steel, but that could be expensive too by the time I have that done.  The steel is not perforated, but has a fair bit of surface rust.

[bevans6]

I use dilute phosphoric acid in a spray bottle, it converts the rust to a stable compound thusly (Wikipedia);

Rust removal

Phosphoric acid may be used as a "rust converter", by direct application to rusted iron, steel tools, or surfaces. The phosphoric acid converts reddish-brown iron(III) oxide (rust) to black ferric phosphate, FePO4.

"Rust converter" is sometimes a greenish liquid suitable for dipping (in the same sort of acid bath as is used for pickling metal), but it is more often formulated as a gel, commonly called naval jelly. It is sometimes sold under other names, such as "rust remover" or "rust killer". As a thick gel, it may be applied to sloping, vertical, or even overhead surfaces.

After treatment, the black ferric-phosphate coating can be scrubbed off, leaving a fresh metal surface. Multiple applications of phosphoric acid may be required to remove all rust. The black phosphate coating can also be left in place, where it will provide moderate further corrosion resistance. (Such protection is also provided by the superficially similar Parkerizing and blued electrochemical conversion coating processes.)

I happen to use POR-15 products on my race cars, so I just buy their Metal Ready product, which is mostly Phosphoric acid anyway.  I haven't noticed it to be very expensive, I honestly don't know how much it costs.  It goes a long way in a spritz bottle.  http://www.por15.com/METAL-READY/productinfo/MRG/

Brian

[TomC]

I've had good luck with good old Rustoleum.  They make a over sound rust primer that works well. Good Luck, TomC

[Chaz]

I have a little experience in this as well.
To have my bus blasted from the top of the bays up is 300.00 I think that is a awesome price.
As for paint and rust inhibitor, I think two part polyurethane is the best. Period. It's actually water proof. Primer is not. Acid etching has proven to be a bad issue when it comes to the final paint job. "Can" cause problems.

Check out this site:
http://www.southernpolyurethanes.com/homepage.htm
It's what I use for the primer on anything. The company and the guy that owns it are exemplary. You can actually call the owner anytime and get outstanding information on paint or problems or whatever issues you encounter. He also has a few standard paints left "I think"!!.

After finding this place, I can honestly say you are messing up if you don't check them out....IMHO.

Chaz

[eddiepotts]

If it is just frame or something hidden you can use ospho. I think that's how you spell it. I get it at Home depot for around $25 a gallon if I remember right. It comes in a green bottle in the paint department. it is an acid that converts the rust to a primer then paint over it with spray can undercoating. I have used it for years on my cars and never had a problem. It will eat concrete so put something down. I looked at the Home depot site and could not find it. But here is a link to it with reviews. http://www.jamestowndistributors.com/userportal/show_product.do?pid=557&familyName=Ospho+Metal+Treatment

[bevans6]

Ospho is another phosphoric acid product, there are a ton of them and I think they all work about the same.  As noted above, if you need to have show quality paint over it, you have to be really careful about how you prep after this kind of stuff.  I just use brush on paint like Rustoleum or POR-15 over it.

Brian

[Songman]

I've used RustGrip and really like it. It is heavily used in marine and off-shore applications. Anything that can stand up to that can certainly stand up to my projects. I also used their thermal coating called SuperTherm. SuperTherm stops 99% UV, 92% Visual Light heat, and 92% conductive heat and cold. Additionally, it blocks 68% of sound waves. These products are made in Canada. I have a friend here in SoCal who is a distributor if anyone is interested. I have used both of these and will definitely use them on any future bus project.

http://www.eaglecoatings.net/content/rustgrip.htm
http://www.eaglecoatings.net/content/supertherm.htm

I don't know if I would call these inexpensive. They are around $100 per gallon. But for what they offer I think it is a very good deal.

[steve wardwell]

we owned a steel hulled schooner for 10 years and swear by a rust inhibitor called  Coreaseal.  We would remove all loose rust apply coreaseal  with a brush and paint in the correct color 2 days later. 5 times better than ospho  and seals tight and held up against the salt water. I know of a shipyard that will  slightly rust a new boat then apply coreaseal to aid in the adhesion of the next layers of paint to the hulls for a long lasting paint job.........s.......

[Busted Knuckle]

While I have no particular experience in this area, I tend to stick by the old rule "Ya get what ya pay for!" or vise versa "If ya don't wanna pay, it ain't gonna pay!"
  BK 

But @ $30 gallon what ya got to lose? If it don't work pony up and buy something that does! It's a gamble either way, but hey so is owning a bus!

[divinerightstrip]

I am saving up for some rustbullet myself. I used it when restoring my rabbit, and I was so happy with the quality of the product. Better than rustoleum, por-15, etc. A little goes a long way.

I recommend "doing it once, and doing it right"

[steve wardwell]

"I recommend "doing it once, and doing it right"................................................................AMEN !!!                                                                                                                                                      

[robertglines1]

to open up a can of worms....back in the day---we used diesel fuel sprayed on rusted barges (fresh water) let set a couple days then sprayed with enamel (oil based paint)did a good job on a large area that is abused and subject to year round weather..still do this on antique equipment..the diesel stopped the rust and soaked in and help enamel ad-hear..for what its worth...we also use a large tank with baking soda water mix and run 12 volt Thur piece to be DE- rusted to clean old rusted parts.leaves bare metal...old time practices..rite or wrong.it works for us..the modern way is for sure much better..trivia      

[belfert]

This is actually for the used trailer I bought to pull behind my bus.  I am basically rebuilding the entire trailer.  I am replacing all of the aluminum skin on the entire trailer.  While the skin is off I need to fix all of the corrosion/rust issues.  Most of the rust is just heavy surface rust, but I actually have to cut out and replace a few pieces.  

I would prefer not to spend $150 to $200 on Rust Bullet because I have already spent a fair bit of money on the trailer.  For the bus it would be less of an issue.  I'm thinking I will just use a wire brush in my grinder to remove what I can and then use Rustoleum rusty metal primer.  Most of the frame should be nice and dry with new aluminum skins.

I'll have spent between 50% and 60% of the cost of a new trailer when I am done.

[grantgoold]

Living in the west without salt!

Grant

[belfert]

Cost is just one reason I don't want to use Rust Bullet.  The other reason is the time required to get the Rust Bullet.  Shipping would take three or four days.  I am still hoping to be reinstalling the skin by Monday.

I started removing the old skin last night and discovered the rust is worse than I had thought.  I'm not sure how the uprights behind the skin are rusty all the way to the roof.  I understand why the bottom is rusty due to the salt exposure.  I don't think I will have any more rust issues with the parts covered by the aluminum skin if I clean and paint it.

I hate salt.  I never realized salt could cause that much corrosion to aluminum.