Need to paint some rusted steel

[alpaca]

I am making a couple largish (~3x5ft) target stands out of 1x1 steel tubing. It is pretty much covered in rust and is pitted. It doesn't need to be showroom quality and I do not want to spend a ton of time grinding off all the rust or spend a lot of money on it. The paint is inevitably going to be damaged by fragmented bullets around where the steel targets will be hanging, but I still want to make it look nice.

Advice? I was thinking about quickly going over it with a 36 grit disk on a die grinder to get all the loose rust off and then using some sort of rust remover/sealer type primer and then spray painting it but I don't really know what to use.

 

[Bobcatter]

I agree with the disc to knock off the loose stuff. I've used a product called Krud Kutter that you spray on, it chemically reacts (strong odors, do it outside) and converts the rust to black material. You can then paint over that if you like. I got the Krud Kutter off Amazon for about $12 a quart. They make other stuff available at you local auto parts, but Krud Kutter seemed to be a stronger solution to me.
Also, the spray undercoating makes a nice flat finish and smooths it over. It might be too sticky if you have to handle the parts thought. Good shooting!

 

[tarbellb]

I like to use my 5" orbital sander with a 60-120 grit. Its quick and knocks off most the rust. Any left over, super deep stuff I then hit with my grinder and a flap disc.

Wear a respirator or mask!

I think using some sort of metal treatment after will net you better results. I usually do a wipe down with some denatured alcohol.

 

[Zeke]

Knotted wire wheel then the phosphoric acid. Rinse, prime and paint.

 

[TheEquineFencer]

Use a mask of some sort, the lead dust is not really good for you.

 

[creativecars]

Wire cup brush on a grinder... done in 10 min.
Wipe clean with thinner.
Brush/ spray a coat of Rust-Oleum Rusty Metal Primer
Paint the color of your choice.

 

[alpaca]

It's not rusted through but there is seriously a lot of rust on it, not just surface rust. It has been sitting outside for god knows how long. I seriously doubt there is any way to take it down to the metal short of sandblasting that won't take hours.

Wire cup brush on a grinder... done in 10 min.
Wipe clean with thinner.
Brush/ spray a coat of Rust-Oleum Rusty Metal Primer
Paint the color of your choice.

Is a wire cup brush that much faster than a 3" 36 grit disk on a grinder? I spent a solid 5 minutes grinding off rust just so I could weld 2 **** joints.

Knotted wire wheel then the phosphoric acid. Rinse, prime and paint.

just spray the acid on and rinse it off?

 

[theoldwizard1]

Hand helg wire brush to get the loose stuff off. Spray Rustoleum red oxide primer. Your choice of Rustoleum ant-rust top coat.

Cheap. Fast.

 

[Zeke]

just spray the acid on and rinse it off?

Well, there is a bit of time needed for the acid to work. The secret is to keep it wet using plastic wrap, trash bags, cling wrap, whatever. Give it some time. An hour may be sufficient.

Hand helg wire brush to get the loose stuff off. Spray Rustoleum red oxide primer. Your choice of Rustoleum ant-rust top coat.

Cheap. Fast.

RS RO primer is not necessarily a rust converter primer, but I believe RS does have such a product.

 

[dadsEH]

Why bother!

 

[creativecars]

It's not rusted through but there is seriously a lot of rust on it, not just surface rust. It has been sitting outside for god knows how long. I seriously doubt there is any way to take it down to the metal short of sandblasting that won't take hours.



Is a wire cup brush that much faster than a 3" 36 grit disk on a grinder? I spent a solid 5 minutes grinding off rust just so I could weld 2 **** joints.



just spray the acid on and rinse it off?

Well you are not going to get every speck, but a good part of it and yes it does go pretty quickly. The rusty metal primer does work best with a bit of rust, so the spots left from the wire brush will be ok. I have a 4" cup brush on a bigger 7/9" grinder that I use for trailer frames. It will give you a workout, hold on tight.

 

[Eriehunter]

I just used a wire cup wheel in my grinder to get the loose stuff and dust off, washed with de-greaser and water then brush painted it with Chassis Saver paint. Chassis Saver is a rust encapsulating paint, it will need to be top coated or it will turn chalky with exposure to uv rays.

 

[zkling]

What I would do is clamp them all together side by side and then to the ground or something stable. Then run a cup brush in a 4.5" grinder over them, flip 90° and repeat. Shoot with rustoleum rusty metal primer (the brown stuff) and then a color top coat or 3.

Word of caution, hopefully your shooters can keep it on target. I made up a few real nice stands only to get completely destroyed in <20 shots from taking a friend that had never shot a high power rifle before shooting. A few hours of work down the drain.

 

[BlackjackNA]

1. Molasses, (fermented) Simply brush on, as many coats as possible... I'm doing this with my trailer frame now - seems to be working.

2. Formula 3000 (the can states wonderful results from painting directly on rusted material.

 

[n8n]

electrolytic? Will take a day or so, but most of it is just cookin' in the tank, you can be sipping on a tasty beverage and watching football while it's doing its thing.

 

[PT Doc]

If you don't want to invest time then wire cup or wheel, flap disc then prime and paint.

 

[that-guy]

get as much of the loose **** off as you can. then coat with POR-15...if need be, sand the POR-15 and paint over top of it. that stuff is hard as rock after it cures

 

[alpaca]

What type of por-15 would work best? There seem to be a lot of types.

 

[404]

I use ospho most of the time.. Paint over with any oil based paint (not water based paint) The advantage is you can verify all the rust has been converted before painting over and hiding everything.. sometimes a second coat of ospho is appropriate.

Regards,
404

http://www.ospho.com/

 

[countryroad82]

For quickie **** jobs I will hit the loose stuff with a scraper, knock at it with a cup brush on a grinder, if I'm in a good mood I'll wipe it down with laquer thinner and shoot my paint.