I'm not sure what a "salt rig" is, but if you mean a water softener to get the iron out of water, then click here
Or a rust disolver? Click here.
And Caterpillar uses a special goop on one of their PayLoaders that has to work in salt mines, etc. Click here.
But to be on topic here, you're probably talking about:
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Several manufacturers offer rust-conversion chemicals. Mar-Hyde One Step, Permatex (Loctite) Extend, POR-15 and Plasti-Kote’s Neutra-Rust are brush-on chemicals that react with rust to form a tough, black-polymer barrier that prevents the rust from spreading.
RestoMotive Laboratories offers a floorpan and trunk restoration kit that allows you to repair minor-rusted metal. The kit comes with all the simple handtools and chemicals (including its POR-15 rust conversion) to remove rust and neutralize, putty and paint your floorpan.
RestoMotive Laboratories (POR-15)
P.O. Box 1235
Morristown, NJ 07962-1235
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