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Can anyone suggest any cheap products on the market to prevent rust forming? I`ve noticed slight `bubbling` around the wheel arches of my lovely escort and I don`t want this to be the beginning of the end for my beloved car.
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The ultimate cure is to put in a new body section readily available cheap and not difficult to fit.You can paint and fill for ever and it will come back eventually.
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If it's coming through from underneath you are stuffed....
Best bet is clean out all the crud from under the arch, cover area in Jenolite then a zinc rich primer paint and lot's of underseal when dry. If you can get close access from the inside - to where the inner and outer arch meet - clean it up and squirt zinc rich primer into the gaps. Then plenty of waxoyl, suitably thinned so it runs. Probably a good time to treat the rest of the car with waxoyl or similar as well (Dinatrol gets good write ups). Once it's started all you can do is either slow it and delay it being an MOT failure by using products or cut out all the rust and weld in fresh, paint and coat with underseal and keep arches clear of crud and wash regularly in winter.
If it's surface rust from scratches then rub down the area until it's shiny metal, any deep rusty bit's you can't get at treat with Jenolite. Fill with body filler. Paint with zinc rich primer and topcoat. Polish area in a few weeks then sell the car whilst standing in front of repair work....
I've found Jenolite and the zinc rich primer (Isopon 182) to be pretty good (tested on scrap steel left outside - unpainted Jenolited steel remained pretty rust free. Zinc rich rusted less than ordinary grey primer.).
Piers
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Ditto first sentance Piers.
I agree with all your methods in attempting to stop rust with the many products on sale.
I have spent hours and hours (in the past) spreading/painting on all these products only to see the bubbles appear again within a year.
Now I'm for the cut/weld/repaint methods....except where a car has little use in the wet and is garaged. Then the Jenolite/Zinc primer/Waxoyl/paint can last a lot longer.
David
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I tried last summer to clear up some surface rust on our 94 Astra. Wire brush/Jenolite/Jenolite Primer/Top Coat on a hot day - 6 months later the bubbles were back. I've always ensured the whole car is regularly washed in winter, including arches etc. A Quote from a bodyshop was next as we intend to keep this car for a while - £250 as "the only way to get rid of the rust completely is sand blasting" which requires trim/bumper removal. This is surface rust, not coming through from the inside and nothing like a long departed MGB I once owned. Surely small patches of surface rust (some from scratches - the paint is very soft) should be curable before terminal rot sets in?
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Robin,
If this is truly surface rust then you should be able to hide it for much longer. Where you see rust bubbles usually there are tiny pinholes through the metal and that is where the moisture comes from to make it bubble again.
Often the bodyshop will do a longer lasting repair by knocking in the dodgy surface and adding a wad of filler. This takes longer to re-appear as a blemish but when it does all the filler will drop off.
HJ is right about the amount of serious seam corrosion on ten year old Fords. They got it badly wrong at that time.
David
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I agree having spent many an hour with rust proofer and primer on a mkII Escort to no affect. I know cutting out is an option but I always thought it was a major expensive piece of work. How much does this kind of job cost, I recently sold a 94 L BMW 318 for this reason. It seems to be a thing of the past with most cars although 99% of owners (and garages when selling valeted cars) still leave enough soil for a small crop of potatoes packed up in the arches. Ian
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Rust can be a very serious problem with any 10 year old Ford (Fiesta, Escort, Sierra). Once it's serious and structural the message it's trying to tell you is "Please recycle me. My design life is over."
HJ
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Yes if it's caught early enough, but in my experience it either doesn't start at all (94 toyota carina) or it's starts and it can go on the surface then it'll get into the seams and then as HJ says ...time for the baked bean can!
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The problem is that the area of the metal that shows the rust is a fair bit smaller than the total area where the chemical process has already started. I can remember spending countless hours with all sorts of wonder treatments to try and cure it, but none worked for more than a short time.
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Any thoughts to perhaps fitting wheel arch trims to the escort? Doesn`t get rid of the rust but it certainly hides it well?
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Iv'e tried every new wonder jocum sold by Halfords and the like for 40 years and up to now have never found anything which works for more than a few months.
They tought me at my apprentice training college that steel won't rust unless it has oxygen to help the oxidisation which is natures way of reverting the metal back to its origional form of ore.
But when i see these fellas going down to the bottom of the ocean to old ships such as the Titanic and theyr'e covered in rust I think where's all the oxygen coming from.
Does anyone remember when we converted from positive earth cars to negative earth (can't remember why) we were advised that car bodywork wouldn't rust as quickly. Perhaps they were right but it could be more likely better steel and application of paint,
Alvin
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Underwater Oxygen.
Water is H20, there's some oxygen there?
Or perhaps the rust on the Titanic is corrosion due to the salt in sea water?
MMJ
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On the subject of rust, I bought a 5 year old austin metro (don't laugh) about 11 years ago.
It was absolutely immaculate.
However, rust started to spread around the fuel cap within a month of buying it and I was forever buying "rust converter" type stuff and paint to try and remove the rust.
It was like painting the Forth Road Bridge, to coin a phrase.
Still, the car lasted 2 years and depreciated from £2500 to £500 so £1000 a year not too bad for 10,000 miles pa.
The best car I had rust-wise was a calibra. Eight years old and no rust at all, after 3 years ownership.
Then the head gasket went, so it had to go. No point spending £2000 on a £3500 car. I'd had them skimmed for £500 some months earlier, but it didn't hold. 30 mpg (petrol) and 10 mpg (water) in the end!!!
MMJ
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The oxygen responsible for underwater rusting is dissolved in the water, rather than the stuff that's chemically bonded to hydrogen. The dissolved oxygen is the stuff the fish get at to live, but because there isn't very much of it, fish need gills to allow a much greater flow of water over their respiratory membranes. The salt in the water acts as a catalyst, speeding up the process already happening, but not actually participating in it. I read this forum with interest, but generally don't know enough to contribute. I am, it must be said, pleased with the slightly less agressive tone of the past week.
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Roland,
You don't need to "know" anything in particular to post here. If you appreciate civility join the ranks and help the balance.
Regards,
David
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Darcy mentioned insulating his - earth radio to suit his + earth car. I've changed a few Morris minors from + to - earth so as the owner could fit a modern radio. Just change the battery leads round, swap the coil LT leads over, re-polarise the dynamo, Job done.
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My 1964 Austin Cambridge was positive earth. Someone at work gave me a negative earth radio and I had the bright idea of wrapping whole thing in plastic bag for insulation. So I connected it up and it worked too until I plugged the aerial in. Then BANG!
Another valuable learning experience ...
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Darcy,
Brilliant idea the plastic bag....
I would never have thought of it and after your experience I'm pleased I didn't.
regards
Alvin
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As I remember it, in the electrochemical series, zinc is below steel, so is good as a sacrificial metal. Aluminium is above steel, so the steel rusts faster when in contact with it. So, never use aluminium mesh as hole reinforcement prior to filler, use perforated zinc, though I've not seen it on sale for years. (It used to be used for ventilation holes in meat safes, pre fridge days!). It cetainly explains why all the carefully painted nuts on the crankcase of my motorbikes used to rust so fast, when the cadmium plated ones didn't.
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I was speaking to a gang from the Rover P6 Owners Club at a rally a few months back regarding how they keep rust at bay from their motors. Some of these guys said they would treat the areas by cutting back the rusty metal with a hacksaw to the bare metal. Then a generous painting of Jenolite, Hammerite or Rust Proof (another proprietary product). Then use an aluminum mesh to plug the hole and then fibreglass / filler and then primer etc ..
This would keep it at bay for small to medium sized rust patches for a while. However, it was best to either replace the panel (they are bolt on unstressed panels and very easy to maintain) or have it cut and welded.
As panels are expensive they all agreed that in the long term solution the best is cut and weld, a couple of coats of zinc primer, paint and then a very generous application of either Waxoyl or Dinitrol underneath.
One owner of an immaculate original P6 had it Dinitrol'd from new and successive applications almost every year. It looked great, the only rust patch he'd suffered was the proverbial battery box problem owing to a leak of acid from the battery.
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I've pretty much saturated my old Escort in Waxoyl. I found the best time to do it is on a very hot summers day as it runs into thecracks and crevices. Best to use a high pressure sprayer as you can get a mist that puts a good coating in hidden / difficult to reach areas. The car was 'Ziebarted' (?spelling?) from new and that seemed to do a pretty good job but had gone very hard and rust ate it's way underneath. Biggest problem was where previous 'cut out and weld in new' repairs hadn't been done well enough and just caused more rust. I pulled out some very good condition plates - the original metal had obviously been taken back to shiney to get a decent weld but the paint around had lifted through the heat and a coat of underseal slapped on top. The plates stayed in good nick though - mind you they were about 4 mm thick!
Unless the car is a classic that you want to keep or you really like the model and every other one available is also rusty the best bet is repair and sell before rust comes through again. And go and buy another one - you now know where to look to get a good one and can 'prevent' - much better than cure!
Piers
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I'd agree with the majority of contributors - the only real answer to rust is to cut out the rusty areas and weld in new metal. For keeping rust at bay, I've found Waxoyl to be excellent. Works on both repaired panels and also on lightly surface rusted panels, underfloor etc. It must be seriously thinned with white spirit to ensure it penetrates the seams etc, but it's worked well on my '58 Minor for about 20 years. Even seems to dramatically slow existing surface rust. I assume it does this by excluding the atmospheric oxygen without which the iron -> iron oxide reaction can't proceed.
I've found most of the Waxoyl applicators pretty poor though, with the exception of the one which resembles a 'Killaspray' garden sprayer. If you have access to a compressed air spray gun, though, use that.
regards
John
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Sorry, a bit late on this one. A vehicle body is one huge electrolytic cell,and as with all such cells the anode (i.e. the steel body shell) disappears over time. Covering the steel with paint promotes electrical stress points in the body leading to localised erosion of the anode (i.e. rust spots). Once it's started you really can't stop it.
In a marine environment they bolt on sacrificial anodes, sub-sea, and these are normally made of zinc or aluminium (I think, although I eagerly await a chemist to put me right). I've seen these things hauled out of the sea, off-shore, and it's amazing how much metal goes in just one year.
With regard to cars I read a very informative book about 20 years ago, by an Australian author who advocated fixing zinc washers to various parts of a car body to act as sacrificial anodes. His point was that they could be bolted on all over the place (bumper fixings etc.) where they are not on view and would present a reasonable mass of zinc to the atmosphere.
Zinc rich paints only achieve a partial fix because they don't really elctrically bond the zinc to the steel and they are localy applied to an area of extreme electrical stress.
Car manufacturers either galvanise their bodies (best) or apply an electrophoretic primer (by dipping the whole shell) and this achieves a much lower level of localised stress. Look at a sheet of galvanised corrugated iron and you will notice that is seldom painted and takes decades to rust through, because the galvanised coating (zinc) is the sacrificial anode and it has a massive area.
So what is the answer? Cut out the rotten steel and weld in new stuff - oh, and you could try bolting on some zinc washers!
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Ian Cook wrote:
>
>
> In a marine environment they bolt on sacrificial anodes,
> sub-sea, and these are normally made of zinc or aluminium (I
> think, although I eagerly await a chemist to put me right).
> I've seen these things hauled out of the sea, off-shore, and
> it's amazing how much metal goes in just one year.
>
Not a chemist Ian but deal with corrosion on regular basis, mostly high temperature corrosion actually but here goes. You are correct about sacrificial anodes. Basically where there are two dissimilar metals the less noble metal corrodes, and zinc and aluminium are way down in the table.
Actually aluminium hulled boats are an absolute nightmare to deal with, and quite frankly though they have many good points the corrosion bit scares me silly. They rely on the fact that the corrosion rate is also influenced by surface area, hence your comment about the zinc anodes on a ships hull being eaten away very fast, ie area of anodes to hull is very small.
With an aluminium hulled boat it relies on the fact that the surface area of the aluminium hull is very much greater than the other more noble metals. Hence the corrosion rate per mm of thickness is much slower. Where it all goes pear shaped is if there is a local problem ie the hull is not electrically insulated from a more noble metal. It can be as silly as this. You are working on the engine and drop a spanner which goes down into the bilges. After the choice swear words, I'll grovel for it later you think, and of course forget. Few weeks, yes weeks, later you have a boat at the bottom of the briny due to a spanner shaped hole in its bottom!
Lots of cases where folks have installed new electrical kit, not sorted out the insulation properly and local corrosion set up which eats right through in days.
How they sort this in Aluminium bodied cars I don't know, but it must be possible. No doubt someone will enlighten us.
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As a further anecdote, following your boat in the bottom of an aluminium spanner example (well you know what I mean) the military air transport pepole are paranoid about anything with mercury NOT being transported in one of their aircraft. If the device breaks, the mercury may end up in the bottom of the a/c (aluminium alloy) and form an amalgam, thus eating through the airframe.
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