Can this rust be treated
- Thread starter brainhax
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You can stop any rust by treating the surface with phosphoric acid; I spray it on from a misting bottle and let it dry.
The acid converts the iron oxide into iron phosphate, which is inert. It is a very mild acid, but you should use nitrile or similar gloves to protect your skin. A quick rinse under tap water will take care of any acid which gets onto your skin. Don't store the acid in a plastic container not intended for it; you'll have a mess on your hands next day. Also, do not store acid in plastic containers near any metal you do not want rusted. The acid molecules will leak through the plastic cap seal and once airborne will eat any metal it contacts.
You can prevent rust on bare metal by washing with sodium hydroxide; we call that lye in the upper half of the world. A scrub with alumina powder will remove any scale and the bare metal will be rust–proof for years.
I'd recommend a stiff steel brush to remove any loose material. The acid will only treat the upper few molecules on the surface, so you want that rust surface to be as thin as you can get it. Once the iron phosphate occurs, you will not get to any rust beneath it. This process is not good for thick rust. For that you'll need to sand or ice blast, or use an air powered needle scaler, followed by the acid wash.
The long term solution, as I'm sure you recognize, is to cut out the affected metal and weld in new sheet steel.
The acid converts the iron oxide into iron phosphate, which is inert. It is a very mild acid, but you should use nitrile or similar gloves to protect your skin. A quick rinse under tap water will take care of any acid which gets onto your skin. Don't store the acid in a plastic container not intended for it; you'll have a mess on your hands next day. Also, do not store acid in plastic containers near any metal you do not want rusted. The acid molecules will leak through the plastic cap seal and once airborne will eat any metal it contacts.
You can prevent rust on bare metal by washing with sodium hydroxide; we call that lye in the upper half of the world. A scrub with alumina powder will remove any scale and the bare metal will be rust–proof for years.
I'd recommend a stiff steel brush to remove any loose material. The acid will only treat the upper few molecules on the surface, so you want that rust surface to be as thin as you can get it. Once the iron phosphate occurs, you will not get to any rust beneath it. This process is not good for thick rust. For that you'll need to sand or ice blast, or use an air powered needle scaler, followed by the acid wash.
The long term solution, as I'm sure you recognize, is to cut out the affected metal and weld in new sheet steel.
- Thread starter
- #3
Thanks for detailed explanation
The pics were taken after running all the areas with wire brush.
Should I clean the area further pointed with finger the the pictures above ? I think if I just push with finger it will make a hole there. It's looking like metal though.
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Probably the tip of the iceberg - there's probably heaps more in other areas of the vehicle. Coastal 4wd? Had too much fun driving on the beach and into the salty water? Or trips into the bush driving across/into salt lakes etc?
Good luck, sad to see.
Yeah, phosphoric acid is the immediate stop gap, but if you can push your finger through areas, it all needs to be cut out. Hopefully some of the body work remains...
cheers,
george.
Good luck, sad to see.
Yeah, phosphoric acid is the immediate stop gap, but if you can push your finger through areas, it all needs to be cut out. Hopefully some of the body work remains...
cheers,
george.
As long as the metal/rust is intact, no.
If you can get on top of it, you can us a chelating solution to completely remove the rust. The formula is:
» 1L distilled water (must be distilled)
» 100g citric acid (powder)
» 40g washing soda (sodium carbonate) [you can use sodium bicarbonate, but you'll need 60g for stoichiometric balance]
» dash of dish soap
– recipe scales linearly.
Soak a cloth in it and place the wet cloth on the rusted metal. As long as it's kept wet, it'll convert the rust, without removing any metal. Any metal you can submerge in a container can be saved with this solution. As with the phosphoric acid, it only converts the upper surface. If the rust has gotten under paint, it'll follow it there.
That rust is significant and high up in the rear (top right in the second photo), so just curious, has the truck been driven/parked on the beach (Ocean), used to launch boats, left out in the rain (windows open for months, years), water trapped inside, or??
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- Thread starter
- #8
Will this solution work on surfaces which are really fragile ? Like just poking them with a screw driver makes a hole in them.
If you can, post up a few photos showing the whole vehicle, engine bay, undercarriage, particularly the frame rails---. If the frame has significant rust it may not be safe to drive.
No treatment will make the flaking rusted steel stronger, will just slow down the inevitable a bit IMO/IME.
No treatment will make the flaking rusted steel stronger, will just slow down the inevitable a bit IMO/IME.
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any steel of any thickness, with any amount of rust
The chelating solution is sold commercially as Evaporust. It's the only thing I know of, short of electrolysis baths, that will completely remove rust.
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- #11
@Kernal
Car is clean from outside and underneath.
Main rust is under tail gate door seal. Rear windows. And most hard part is under the roof liner. To start with, is the surface in first picture below ready for primer and paint or I still need to remove all that white paint ? What type of primer to be used ? This area is sold and had only surface rust.
Car is clean from outside and underneath.
Main rust is under tail gate door seal. Rear windows. And most hard part is under the roof liner. To start with, is the surface in first picture below ready for primer and paint or I still need to remove all that white paint ? What type of primer to be used ? This area is sold and had only surface rust.
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So if water is under the "roof liner" are there holes in the roof? You could check around the windshield gasket, the roof, and roof gutters for rust holes. Post up some photos of the roof (and the whole body).
Water is also getting into the cabin from the rear quarter window(s?).
So first thing is stopping water intrusion.
The quarter windows will have to be removed completely (glass/frame/gasket) then address the rust there
which likely means it needs to be cut out with metal welded back in.
As mentioned by others you could "kill" or slow down the rust with the phosphoric acid products but if you apply too much
the primer/paint won't stick well. A two part Epoxy primer (catalyzed) followed by a two part (catalyzed) Epoxy top coat will slow down the rust
but only if there aren't pin holes going through to the other side. But catalyzed (2K) primer/paint is not cheap.
Based on what you've posted up so far IMHO it would be easier/cheaper in the long run to find a body without rust and swap
it for what you've got now, or find another 80 and use the rusty one for spares??
It would help if you showed us some more complete photos of the vehicle so others on the forum who may have for example worked with signifcant rust (or made UTEs out of a LC) might could give you more/better advice.
Water is also getting into the cabin from the rear quarter window(s?).
So first thing is stopping water intrusion.
The quarter windows will have to be removed completely (glass/frame/gasket) then address the rust there
which likely means it needs to be cut out with metal welded back in.
As mentioned by others you could "kill" or slow down the rust with the phosphoric acid products but if you apply too much
the primer/paint won't stick well. A two part Epoxy primer (catalyzed) followed by a two part (catalyzed) Epoxy top coat will slow down the rust
but only if there aren't pin holes going through to the other side. But catalyzed (2K) primer/paint is not cheap.
Based on what you've posted up so far IMHO it would be easier/cheaper in the long run to find a body without rust and swap
it for what you've got now, or find another 80 and use the rusty one for spares??
It would help if you showed us some more complete photos of the vehicle so others on the forum who may have for example worked with signifcant rust (or made UTEs out of a LC) might could give you more/better advice.
Sorry to OP for the highjack . . .
Just bought an old table saw and cleaned it up. Was contemplating how to keep it rust free
Will this work on a cast iron table saw table?
Just bought an old table saw and cleaned it up. Was contemplating how to keep it rust free
Yes, any iron/steel that will rust. What you are trying to do is to raise the pH of the surface. Oxidation needs low pH, which is why acids rust metals but bases don't.
Cool. I'll give it a go
Ditcherman
SILVER Star
If you have to ask, then probably not.
If it’s rough, it will show through unless you use copious amounts of sandable primer. It’s less work and better to get down to a smooth surface, even though it might not seem like it at the time.
As others have said, you need to evaluate the whole body and make sure you’re going to want to finish or don’t bother starting.
You are getting into a lot of work.
Practice, and if you want, paint the part in question but be willing to sand it right back off if you don’t like it. It’s good practice anyway.
There are no shortcuts if you want to do it right.