Best way to remove surface rust ?

What is the best way(or products) to remove surface rust from under a truck ?

Does anyone have a detailed step by step method to treat it…removing, protecting etc ?

 

Friction

 

On smooth surfaces, sandpaper and WD40 works pretty good. On a rough surface you might want to try a wire brush instead of the sandpaper.

 

Spray it with wd-40 then apply friction ?

 

Short of dry ice or sand blasting, there's grinding, sanding, needle scaling and a lot of elbow grease. Then a coating of some rust preventer like POR-15

 

Just spray it with fluid film or wool wax on a warm day. A good coating will cut off the oxygen supply and the rust will remain dormant. This is why we need to replace as the undercoating wears off. It doesn’t cure it , if it’s already there. Rust is like metal cancer, you never really get it all. You learn to control it.

 

Yes. You'll get most of it but there is no way to get all of it. You'll have to coat it with something so it doesn't rust again. Do not use undercoating.

Any pictures on how bad the rust is?

 

yeah I’ll try to take some pics, but really I want to paint under the truck black so it looks better.. at what point am I safe to paint it

 

The worst thing that happens if you paint it too early is you waste your time. If you can get to bare shiny metal using a wire wheel, sandpaper or some other method, clean with a solvent, let dry, apply primer, then black paint. If you can't get to shiny metal and instead are left with pitted corrosion, still clean with solvent but use something like rustoleum rust reformer, then black paint

 

After removing the rust from the back of a truck frame we pressure washed it then sprayed it with POR-15 Rust Remover and let it sit for 20-30 min. After that we pressure washed the frame again and then let it dry for a couple days prior to coating it with POR-15 Rust Prevent. I'm not trying to advocate for POR. It's what we could find in our local stores. Once all is done the intent is to Fluid Film. I normally work with the regular FF, but I know they make a black FF.

I guess it depends on how big of an area you are dealing with.
My son's Duramax project yielded three 5-gallon buckets of rust swept up from the driveway and that's just from just the back end of the truck. We're just starting to deal with under the cab.

 

Baking soda blasting can be done at home if you have a big enough compressor and either open space or neighbors who don't mind the noise and debris.

Harbor freight even sells large bags of blasting soda and the blasting gun they sell is super cheap and works.

You must wear PPE when doing this or you won't live long.

 

Technically the best way is to burn it off with a laser cleaner. May not be the most economical way, but you did ask for the best way...

 

Interesting.... I had never heard of baking soda blasting. I take it you've had good experiences with HF's soda blaster.
I tried HF's 20 LBS abrasive blaster and though it sucked so it was returned. Nozzles would wear quickly and it would clog with the larger grits. Plus, without media recovery it didn't seem cost effective for a large area.

 

Baking soda is not abrasive in the usual sense, so you don't have problems related to abrasives.

It does clump but a bump/shake of it usually fixes that.