Preventing rust!

[mjrally]

Right then what do you recon will be best for preventing rust again, as you can see from the photo below. The front of my car had a fair bit of surface rust on it. Ive ground it all back now with a flap disc but the metal has darkened slighlty in the worst effected area's. so my question is whats best for covering it all? i dont want the rust to re-apear and i can t guarantee ive got to all the nucks and crannies so ideally want a rust-killer type of base coat, before spraying. Ive got about 5 liters of primer already but its just standard cellulose.

Ive read etch primer is a good base but will it prevent rust? also seen the use of red oxide? can this be sprayed over?

 

[langy]

Epoxy primer is anti corrosive

 

[kelsham]

preventing rust

I would use a rust treatment before priming.
Bilt hamber Hydrate 80, Jenolite, or Kurust. If you decide to use Jenolite follow the instructions on the container and give it at least two treatments.

Hydrate 80 is fairly new and so I am unable to say how it performs over time. It is easy to use though.

In my opinion rust always needs treatment before painting.

Regards Kels.

 

[Chickenjohn]

The trouble with all those "rust treatment " paints and converters etc is that none of them work! All they do is convert the top layer of the rust. Fine if you are going to sell the car in a few months but no good if you want to keep it as all the rust will be back within a year or two.

The only way to deal with rust is REMOVE IT ALL!

Chemical dipping and e-coating or media blasting are the best methods for this.

Perhaps you could remove all glass and interior on the car, mask off the engine and have the body shell blasted then etch primed? Or better still, remove the engine and all removable panels and have the car blasted and etch primed as a rolling shell. If your budget is tight, the best (but far from perfect) home DIY method is repeated wire brushing using angle grinder and drill and repeated application of 10% Phosphoric acid. This will turn the rust black and then you wire brush again. When the metal no longer turns black when you apply the phosphoric acid in the pits in the surface then you have removed all the rust and you can etch prime the car and paint it.

 

[grim_d]

Give bilt hamber deox gel a try, from what I have seen with my mates using it is that it good stuff, it gets removed after it's done its job you can see if if needs another treatment or not.

It should leave the steel nice and shiny.

 

[mjrally]

The trouble with all those "rust treatment " paints and converters etc is that none of them work! All they do is convert the top layer of the rust. Fine if you are going to sell the car in a few months but no good if you want to keep it as all the rust will be back within a year or two.

The only way to deal with rust is REMOVE IT ALL!

Chemical dipping and e-coating or media blasting are the best methods for this.

Perhaps you could remove all glass and interior on the car, mask off the engine and have the body shell blasted then etch primed? Or better still, remove the engine and all removable panels and have the car blasted and etch primed as a rolling shell. If your budget is tight, the best (but far from perfect) home DIY method is repeated wire brushing using angle grinder and drill and repeated application of 10% Phosphoric acid. This will turn the rust black and then you wire brush again. When the metal no longer turns black when you apply the phosphoric acid in the pits in the surface then you have removed all the rust and you can etch prime the car and paint it.

The car is totally stripped now (the photo's is quite old), but the budget wont stretch to getting the shell dipped. so i need a solution i can do myself. i think ill try ang get as much off with the flap disc and with the wire wheel.

Phosphoric acid seems abit dangerous personally? i assume this would have to be done with BA and in a ventilated area??

 

[Weldinator]

The trouble with all those "rust treatment " paints and converters etc is that none of them work! All they do is convert the top layer of the rust. Fine if you are going to sell the car in a few months but no good if you want to keep it as all the rust will be back within a year or two.

The only way to deal with rust is REMOVE IT ALL!

Chemical dipping and e-coating or media blasting are the best methods for this.

Perhaps you could remove all glass and interior on the car, mask off the engine and have the body shell blasted then etch primed? Or better still, remove the engine and all removable panels and have the car blasted and etch primed as a rolling shell. If your budget is tight, the best (but far from perfect) home DIY method is repeated wire brushing using angle grinder and drill and repeated application of 10% Phosphoric acid. This will turn the rust black and then you wire brush again. When the metal no longer turns black when you apply the phosphoric acid in the pits in the surface then you have removed all the rust and you can etch prime the car and paint it.

Thats not entirely correct, the hydrate 80 is the only stuff ill ever use with their cavity wax spray as well. I tested the hydrate stuff in saltwater for months and was still perfect, yet all the other cheaper stuff rusted. The thing is rust needs oxygen to start rusting and hydrate 80 converts the rust, puts a strong barrier on which seals it from oxygen. In some places rust is impossible to remove like inside a good sill, mine has surface rust inside but could not reach the other end well enough to fully remove the rust so i used the hydrate 80 treatment, cheaper and less time than replacing the whole sill in the first place.

 

[eil]

I have gone right off the hydrate80 and don't think i will be using it again, I will use the detox c or the gel to remove rust if I have got all night to let it do its job, then I think a phosphoric wash before epoxy coating the metal, if I haven't got the time to wait I was thinking of using a stronger phosphoric treatment like http://www.bonnymans.co.uk/products/product.php?productID=6183&categoryID=1414
But it is a strong acid, so precautions have to be taken with its use. There is quite a bit of debate on various sites all over the Internet as whats best, I guess you will have to make up your own mind as to which way to go, but personally I don't like the rust converting route or smothering the rust in latex and hopefully trying to contain it, here is something you might find useful even though its quite old. http://www.jefflilly.com/shelby-mustang-restoration/metal_prep.pdf

 

[Chickenjohn]

Thats not entirely correct, the hydrate 80 is the only stuff ill ever use with their cavity wax spray as well. I tested the hydrate stuff in saltwater for months and was still perfect, yet all the other cheaper stuff rusted. The thing is rust needs oxygen to start rusting and hydrate 80 converts the rust, puts a strong barrier on which seals it from oxygen. In some places rust is impossible to remove like inside a good sill, mine has surface rust inside but could not reach the other end well enough to fully remove the rust so i used the hydrate 80 treatment, cheaper and less time than replacing the whole sill in the first place.

What I wrote is entirely correct! I've used Hydrate 80 as well, just another "rust converter" that doesn't really work! Scratch it and the rust is still there underneath, biding its time, waiting to come back and eat your car again!. It is the wax protection that is stopping the rust in your case, or at least slowing the progress of rust , for a while anyway. Wax can seal out water and air for a while.

The problem with these converters is that they only convert the very top layer misleading you in thinking the rust is somehow 'sealed" . This is not the case, rust flakes and comes off, it is not a suitable substrate for any paint and whatever you paint over the top will fail.

The only solution to rust is to get rid of it all!

 

[Weldinator]

I do where ever i can because i agree removing it totally is the only real way to keep it at bay, but in the sill it will have to do, i have made drain holes in the sill as well. I tested it and it works and is used for oil rigs and bridges so it must be good enough. I wont mess with the acid stuff and if i did how would i seal paint inside the sill ? I cant believe that Jeff was using it with no nitrile gloves on ?? The cavity wax they sell keeps/drives water out and sprays into every crevice so imo there will be no rust coming back again if ever.

Like i said rust needs oxygen to carry on rusting away, if you seal the top thin layered rust then it wont come back, if it does im sure it will be in around 40 years time, not 10/15 like the 205 usually does. The hydrate says to remove as much rust as poss so only a top layer is to be coated and is good to use on bare metal of which i tested as well. My sills had loads of bubbly hard rust that took ages to remove with special tools and scratched arms etc, i cant use rust remover due to the fact i cant get it out from the other end of inside the sill. The wax also if used on rust, it also seals the rust too so that 2 sealants at play, so no oxygen can get into the rust. The car will be garaged and driven weekends only any how. I will also use their primer too, its high in zinc.

I have made holes in the sill to put more wax in after a few years time when the old stuff has lost its effectiveness.

I did say its not entirely correct because i tested it myself with perfect results on bare metal and rusted metal, did you ?

Apart from fitting new sills at a large cost my way after lots of research is the only way to do it well and cheap. Other areas of a car i agree get rid/sand the rust away totally, not worth doing it badly.

Cheers.

 

[Chickenjohn]

I tested hydrate 80 on metal that has been cleaned as much as possible- so was a mixture of clean steel and light surface rust. I scratched the surface after the hydrate was cured and was dismayed to find rust still underneath- and the water in the hydrate 80 formulation had quickly caused the clean steel to start rusting- not good ;-(

I tested this because to my great annoyance a bit of paintwork I had done on one of my classic cars- on a rear wing- just surface rust- with the hydrate 80 as the first layer- had failed within a year or two- certainly not 40 years! Rust bubbling back up again.

Inside the sills, a good cavity wax will slow corrosion, which is about the only thing you can do to treat rust inside a cavity. Other than getting the car dipped and e-coated at great expense.

BTW, I did a test with 90% zinc primer on cleaned up rusted steel and that performed a lot better than the "converters" did- lasting several years on the flange of a front wing.
This confirms the test that practical classics did about 10 years ago (when PC was still an OK magazine) - they tested various "rust converters" anti rust paints, hammerite and zinc primer.
Worth digging up a copy if you can find it.

The only paint that worked for any length of time in their test was the zinc primer, the rest failed after salt water sprays etc. Even then, i would not rely on Zinc primer- the only way to stop rust is remove it all, completely.

 

[eil]

My findings is similar to chickenjohn`s as well, I used the 80 on a few vehicles and not on a test piece left out in the weather, another problem I have found is that paint does not adhere to it very well and if you abrade it first you run the chance of scratching through the coating which defeats the object, It will be interesting to see the results of the latest Practical classics test with the Sierra.

 

[kelsham]

rust

Well quite a lot of disagreement over the best course of action.
It does say on the hydrate 80 instruction sheet I have that it is purposefully made runny in consistency so as to wet the rust better. I agree that any rust converter will have rust that it cannot reach, still beneath the coating.

I have used Jenolite for many years and if this is attacked with abrasive material after using as per the instructions, rust will still be beneath the phosphate coating.

This does not mean it is not worth using. I have used it and after carefully priming and painting the surface it will contain the rust by keeping air from the surface of the metal.

My friend decided that he would wire brush the wings on his BSA Scout 1933 and then just prime and paint the wings. One year later they had rust bubbling up.

I have just been into the garage to inspect some work I carried out on my XJS bodywork ten years ago.

I used Jenolite and Bondaprimer as the first stage and finished with cellulose. Still no sign of rust.
I agree serious rust needs cutting out and replacement metal welded in. But light surface rust can be stopped for as long as air cannot reach the metal beneath the coating of paint.

Even dipping the body has its limitations, I would worry that wetting the body seams could lead to later problems. Any treatment has to work inside the sills and other closed areas.

There is no easy way, hard work with wire brushes polycarbide wheels etc. then a couple of treatments with Jenolite and a coat of the zinc primer mentioned earlier will slow the inevitable down considerably.


Regard Kels.

 

[mjrally]

From what you guys are saying, i think im going to flap-disc back and then wire wheel back all the bodywork, and then look at an acid based product to clean the metal. Ill then look a putting a zinc primer on as suggested and a few cellulose primer layers after that. Thanks for the advise guys!!!

 

[keithski122]

I'm with Langy on this one, from what I've read epoxy primer is best in this situation.I'm just doing my beetles paint and am going to use epoxy primer.Any rust treatment stuff I've used before is not a wonder potion.
What I would do in your situation is use a wire brush on a drill to clean up all places you can get to, rust treat places you can't reach, then epoxy primer to seal followed by a normal primer over that.Then top coat and waxoil any cavities.

 

[Chickenjohn]

Epoxy primer is great over completely rust free steel, but will not stop existing rust from flaking off and coming back to haunt you!

 

[langy]

Yep you need to get the steel as clean as humanly possible, then it will keep the steel nice.

Epoxy primer is great over completely rust free steel, but will not stop existing rust from flaking off and coming back to haunt you!

 

[Weldinator]

Where can you buy epoxy primer from, i have search google and it seems i find them from USA ? E-bay not much better either.

 

[langy]

Where can you buy epoxy primer from, i have search google and it seems i find them from USA ? E-bay not much better either.

I get it from my local auto paint factors, only decent stockyard will have it though, you won't get it from the cowboys

Metalflake.com sells it pre mixed, I prefer to have it colour matched as my local guy has it on the scheme

 

[Weldinator]

Nope they dont sell it now i just called them. Seems its hard stuff to get hold of.