What is the best chemical for removal/treating rust from steel other than sandblasting. I have a small area on myC3 frame. Im planning on possibly restoring it in a few years. Just want to keep it from getting worse for now.

 

All depends on where it is located...and...if there are factory seams or welded lap joints around this rusted area. The reason I am concerned about seams...is if you want to use the POR-15 system. It requires using a cleaner and acid etch...and then rinsing it with water BEFORE you apply the POR-15 product. And with the acid etch (which I have used numerous times) I usually use it when the body is off the frame and the owner chooses NOT to have it sand blasted and power coated....so I can thoroughly wash out the frame and dry it.

I have...in some cases...coated the rusted area with wheel bearing grease and that was all I did...due to the same reason. The car was going to be repaired in the near future...and the grease slowed down or at least stopped the advancement of the rust. but the grease needed to be checked from time to time to make sure it was sealing out the chance of water/moisture getting to the rust. Once again location of the rust and severity of corrosion does play into how it needs to be handled....in my opinion.

Mar-hyde also sells a product called "rust converter" (which is white like milk) that can be applied and converts the rust to a black oxide primer. I have used it also with good results and still use it in certain situations

Hope this was some aid.

DUB

 

An angle grinder with a wire-wheel will take all the rust off leaving clean metal. It has to be an angle grinder, a drill will not have the needed speed.

 

Some rust on the floor boards abd on the frame, the side away from the body. Which of those products can I get locally or easier to find?

 

Check your local paint and body supply stores. I am sure they are aware if the products I have mentioned ...unless they have been hiding under a rock for years. Once again...not knowing the extent of rust scale...it is hard to advise you in what would be the best method...i.e. light surface rust vs. heavy scale.

DUB

 

I live 50 miles from the closest supply store. Ill have to pack a lunch and take a trip. LOL! The rust is light surface rust on the frame and area of 3" x 6". However, I decided to replace the carpet and there is rust around the seat track mount hole medium to heavy scale and one area has a hole throgh it and it's not for the seat track bolt.

 

I work on board ships and deal with rust and corrosion on a daily basis. Of course we have access to industrial removers and converters that aren't generally available to the public; but most use phosphoric acid as an active ingrediant. Phosphoric acid is also used in most over the counter products available in local hardware stores.

Rust, ferrous oxide, is chemically very active and will continue to generate more rust as long as any rust is present. Merely encapsulating it is a temporary solution at best. To stop rust, all the rust must be removed and or chemically converted.

Physically remove all the rust possible mechanically, sand or media blast, wire brush, wire wheel, heavy grit sandpaper, dental picks, whatever. But you will never get all the rust removed simply because the last of the rust is in pits, below the working surface . If the base metal is thick enough you can grind down and remove the surface layer of metal , along with the pits it contains. But this is not always possible or desireable.

Phosphoric acid converts the remaining rust to a stable, inert, ferrous phosphate which is hard, black in color and paintable. Most treatments such as naval jelly or (I suspect) POR contain phoshoric acid in a paintable binder, typically milky white in color, which, while it provides a one step process to convert and encapsulate any rust with a paintable surface, cannot penetrate down into all the pits, allowing active rust to remain, waiting only to resurface at a later date.

My favorite treatment to reach and penetrate these rust pits is OSPHO, or it's civilian counter part, Jasco Metal Prep which is available in hardware stores. It is liquid, can be applied multiple times if necessary, and will penatrate pits, seams and crevices where the others cannot. And it will "dissolve" rust. BUT at the end, it must be throughly rinsed with water, and blown dry with compressed air or a heat gun.

At this point a primer can be applied; for cost and ease of application, Rustoleum "Rusty Metal Primer" brown in color, followed by Rustoleum "Clean Metal Primer, white in color. A top coat of Rustleum enamel is a good choice. Both these primers are waterproof, whereas most spray can "automotive" primers are not. Of course more durable epoxy based primers and top coats are available.

 

Thanks,This is a bunch of good information. I've seen the Jasco metal prep at the local hardware store. I'm getting a gallon tomorrow.

 

Good info. I've also had very good results with the rustoleum brush-on primer and top coats.

 

I just bought a bottle of OSPHO at my hardware store, the instruction on the bottle say nothing about rinsing it off, in fact they say just the opposite, apply as many coats as needed, let dry overnight, then prime and paint

I tried it in a few spots on my car and seems to work really well, I'll let you know when I try it on my floor boards, they need the help bad.

 

Where you need to rinse it off is where it is on bare metal not rust.

On the bare metal it will not convert to black like it will on rust and it will stay wet. Therefore you should rinse and wipe the residue off of the those areas.

 

ok, got ya. thanks

 

http://3mcollision.com/catalogsearch...rust+converter

 

just bought a gallon of OSPHO for 39 bucks at a marine store. I have a rust phobia I have much to try it on first is diff cover on my Excursion! Keep you posted. The other cars, trucks, and heavy equipment.