Used this formulation yesterday and it is bloody amazing! I used half a litre of acid with ethyl and it started really kicking in within about 30 minutes - my finished project is a square metre of angle and flat steel as well as a load of 1 inch square tube, about 50kg weight in total. The reaction surprised me, my workpiece got very warm to the touch. Definitely a job for outside and not the garage, this morning there was a patch of horrible black gunk stuck to the road/footpath outside the house.

What WAS surprising was the effect the spray had on the mill scale - I'd previously only cleaned the parts that needed welding so there was a lot of scale. This morning it was at least 95% gone. Also the galvanised tube had been stripped clean. So this is definately a go-to method for welding prep, way cleaner and safer than using muriatic, and lots cheaper and less effort than grinding.

The metal was left with a coating of black grit, a coarse sandpaper texture. This came off easily with light steel-brushing. I've applied a coat of epoxy primer to one side and it looks immaculate, no bumpy bits, dead flat. So I'd give this methods a huge thumbs up. I've just ordered a litre of phosphoric online, definitely worth keeping some handy.

no it doesnt work on severely corroded steel
it can be added to paints to bind the paint, the iron phosphate turns white which helps most paints stand out too

it can be used on somewhat corroded but still smooth steel parts with scrubbing using steel sponge
corroded steel beams with uneven surface, no not really. the alcohol also doesnt do anything, thats a waste of chemicals.

Why not a phosphate bath. I use it on the Gulf coast all the time. Then the greenies had it removed from Home Depot.

Dog has stage fright by the way his legs are shaking.

Should we use oil and grease remover before spraying the solution? Thanks

Rubber n electrical connection  ???

I’m based in Canada. anyone here managed to get Phosphoric Acid let me know from where thanks.

If I sprayed portions of my cars undercarriage do I need to then hit those areas with paint?

Thanks for simplifying this process . Many videos make it confusing

Thanks for the video.
The 85% concentrated phosphoric acid is highly corrosive. It can cause skin burn, respiratory irritation, and permanent eye damage.

Unlike sulfuric acid which burns instantly, concentrated phosphoric acid is notorious for a delayed burn. It can sit on skin for a minute without stinging, tricking people into thinking they are safe while it damages tissue underneath.

Even if diluted to 18%, it can cause severe eye irritations.2:45 It is used in food products at low concentrations of about 0.5%.

Safety rules for concentrated chemicals:
1. When diluting, add acid to water, NOT water to acid!
2. Wear gloves and eye protections, especially while diluting or spraying.
3. Dilution should be done based on liquid weight, not volume.
4. Take your pets away while spraying chemicals!

Nice bro. Thanks. I subscribe from Tasmania  🇦🇺

Awesome. I've got a car in the rust belt that has structural holes in the control arms and engine cradle, real bad. It still runs good so I'm hoping to stop the rust or slow it down for 9-24 months and but some time

TY 🙏

You can use regular Coke (not Pepsi)  for rust removal as well.  Put it in a tray/bucket and you can soak the rusted part in there for a day and depending on how bad the rust is - typically comes out pretty clean.   Coke has many uses :)

Rubber gloves . Safety glasses

Going to give this a try and see how it does. Do you have to spray it with epoxy primer? Or can you just prime and paint it

cool ! thanks for sharing. I'm going to try that

Straight to the point, I like it!

Thank you so much - Can't wait to try it - looks like phosphoric acid has gone up in price now...

I tried this and it did not work for me. It still looked rusty to me.