RUST

[SambaS]

oh yes you will

[SambaS]

Check out my chassis leg!

 

[Morgan84]

Wax oil or even plain engine/gear oil underneath the vehicle,and spray through all possible box sections. Spray inside door panels,and other internal areas where damp can allow rust to form.Another good thing is to paint hammerite type paint underneath from wings,and vallences etc,and then waxoil/oil them at least once a year. A couple of hours getting messy saves hours of welding later

[Guest Tony Hayers]

Some further reading for you -

 

http://retrorides.proboards.com/index.c ... 725&page=1

 

http://www.mig-welding.co.uk/forum/show ... hp?t=26118

 

http://www.migweb.co.uk/forums/welding- ... urust.html

 

Mr bo11ox, of this parish used a paint supplier that he rated very well (on his Mk 3 Cav). Its in his blog, or someone else who knows the supplier will post it in a bit no doubt.

 

As to Halfords rattlecans, some find them ok but I find them

[phil drolls]

You have to take into account that not all cars were made from the same grade of steel, so what might keep rust at bay on one make of car, will have a hard time on some others. That`s why some folks tried and tested rust prevention suddenly seems to be pants when they try the same thing on a different make. We`ve all read that Rust Never Sleeps, well that`s only true if the steel is shit and already has started to corrode prior to painting. Rust can be stopped. If the steel is sound and good quality, and it`s `encapsulated` 100% by top quality primer and paint, it will remain rust free unless the painted surface is breached by stones and general wear and tear. I`ve done this many times and it works, but I`ve also had nightmares with other cars which, no matter what I used, the rust would eventually creep through within a year, due to the fact that the steel was crap. I used Kurust a lot in the 80s and 90s, but now I`m finding it isn`t doing the bizzo and I`ve used other stuff. Hydrate80 is great stuff, but like everything else, if the preparation isn`t good, the rust will return.

[SambaS]

YO!

 

Did I hear someone (VG) say dipping causes metal warpage? 

[vulgalour]

Dipping causes flash rusting if it causes anything, from what I've seen.  Shot/sand/media blasting is what can cause panel warpage, especially on thing French stuff and some late 80s/early 90s Fords.  Soda blasting is the best thing I've seen used to completely clean back bodywork with minimal damage for maximum effect, I've been really impressed by the end results from it and it's one of the more affordable options of its type, just a bit slower.

 

Prevention is the only option, there is no cure.  For keeping things less rusty I've found localised repairs and keeping a car clean really, really helps.  The Princess is a study in corrosion at present and I've noticed a few areas that rust faster than others.

 

> On the front wing I applied a coat of acrylic rattle can paint, it was a rush job in less than ideal conditions and it has since flash rusted just like your Escort

> Crusty underseal traps moisture and the rust can become rot unseen, this has been a big problem on the outer edges of my floors and sills.  Where the underseal is still a bit rubbery there's no corrosion issues.

> Dirt, amazingly, makes the rust worse.  When the car was washed regularly, any areas of rust stayed the same.  While the car has been in storage both in a garage and later outside in the open the areas of rust have visibly grown and cannot be wiped off so I'll have remedial work to do as a result.

 

On a budget, don't worry about the finish.  Get the rust cleaned back, use a rust converter with a good reputation that you like and then get a good amount of paint on top.  Keep everything as dry as possible and don't let it get too cold and you should have a long lasting repair.  Gloss paint is far superior for keeping rust at bay, it keeps moisture out better.

[Uncle Jimmy]

Acrylic anything is shite. Amongst other things I paint a lot of windows and other joinery products, oil based is the biz for keeping water out.

Hammerite is the bollocks for doing under floors and inside wings. It stays slightly chewy not brittle and I usually blow over it with some underseal. In cavities I use Sika wax- ace, it comes out like cold piss and gets in all the nooks, then hardens and sticks like shit to the proverbial.

Kurust is alright for wee jobs around the engine bay like a brake servo but I don't like it on bodywork as I'm not sure paint sticks to it. Don't use galvanised steel to plate over holes, paint doesn't stick and don't use red oxide primer it's soft as shite and cellulose doesn't stick to it.

Do wire wheel stuff to death before painting it. I think it's good to both clean and provide a key. Cellulose isn't going to want to stick to something that's been sanded to 2000 grit.

As for Volvos, they were at least partially galvanised, and properly hot dipped too not shite electro galvanising. I had a Lotus with galvanised chassis, rest of the car was tat but the 35yr old chassis had zero corrosion. The zinc was 1/8" thick.

[Uncle Jimmy]

And, as someone else has said, clean is good- your hands sweat and that sweat is acid and corrosive. Cellulose thinners before painting and to wipe off dust when cutting back paint and wear cotton gloves.

[Station]

If there's rust, you have to get rid of it. Brushing on Kurust over a big load of pitting and watching it 'convert the rust' is a load of rubbish. There's still rust underneath and it'll come out.

 

Rust is weird though, I've had exposed metal on various cars (a chip for example) and it has never rusted. The MGF had a leaky window seal for years, beneath the seats was always damp and wet, but that area just never rusted.

What causes rust - is it just water, or does it have to have a salt/sodium content? Does air cause rust? Does salt water eat through paint/etc and just attack the metal?

[mat_the_cat]

I've found Hammerite terrible for chipping personally, but aside from the underbody wax type stuff I've not found any paint great at resisting chips.

 

The best prevention I've found so far is cold galvanising solution such as Galvafroid or Zinga, but it's rather soft so needs painting in vulnerable areas. It's supposed to have a similar lifespan to hot dip, and 5 year's experience is showing so far so good. It's a bugger to sand though, as it's so full of zinc particles it smears rather than sands. Needs bare metal and not treated rust though.

 

Which brings me on to rust treatments...there are converters (like BH Hydrate 80) and removers (like BH Deox) but the danger with converters is they may only treat the top layer. For a depressing sight try grinding away a bit after you've treated! Removers are better IMO as they leave shiny steel for painting afterwards, so you know all the rust has gone.

 

Rust needs are and moisture, but is massively accelerated by salty water. All paints are very slightly porous layer by layer, so a thin layer, or on sharp corners will allow moisture to penetrate. With sufficient thickness, they become effectively non-porous. Some cars are zinc plated under the paint so won't rust until the sacrificial zinc layer is depleted. This is much thinner than proper hot dip galvanising, so doesn't resist the rust as long. I've not heard of a monocoque shell being hot dipped, as the heat would warp the panels, so AFAIK, the cars we talk about of as being galvanised, are actually just zinc (electro)plated. This can be done to different thicknesses, so not all plating is equal...

 

The other point I've noticed is that wire brushing on pitted rust can actually just burnish the metal over pieces of rust. I've always known it come back, maybe in 5-10 years, unless ground out fully or cut out completely.

[Split_Pin]

Rust will usually start anywhere that water can seep into and sit, so inside seams where paint cant reach is 9/10 times where it will start and its almost impossible to prevent. I used 3 cans of Dinitrol on my car last night and the metreong lance you get with them is ace. I just kept going until is was pissing out of every orifice and I have leave it to dry in the wind we're having for several days.

[SambaS]

I've been having some fun the last couple of days.

 

My new Monza petrol tank came in the post with a very thin coating of metallic silver paint:

 

 

I gave it a once over with some wet n dry to key the surface and covered it in U Pol primer allover then the top half in Gravi Gard:

 

 

Then ran out.

 

This morning I went and got MOAR, and also found some SIMONIZ red oxide primer that I thought I may as well use up on the bottom half:

 

 

Then I used a full can of Gravi Gard on the bottom half paying extra attention to the seams around the middle.

 

 

Now I am waiting for that to dry, before applying a gloss black top coat to the top and bottom.

 

I am hoping this tank will outlast life itself. But this thread will be updated in due course should anything fail.

 

The devil in my head was saying, just bolt it on as it is and be done with, as I currently have no car on the road, between borrowing my cabriolet back that is on loan. I'm glad I've painted it now. I'm actually having fun.

 

When I get a second hand tank for the MG I will probably use the same process, but include some rust treater and see how "restoring" an old tank compares to the preventative measures in place with the new one.

[vulgalour]

Didn't realise you still had the Monza, did the weldathon get completed on that one?

[SambaS]

VG how have you missed the thread!

 

http://autoshite.com/topic/10840-opel-monza-gse-automatic-running-in-issues/page-5

[vulgalour]

Oh... I appear to have some reading to do!  Not sure how I missed that.  *kettle on*

[nisfan]

All this makes interesting reading, i will be needing underseal/ cavity wax for my bluebird and stanza and have been looking for something better than waxoyl as it doesnt seem that good. Also have to agree on rust converters, ive always had the rust come back.

[mat_the_cat]

I've linked to this before, but it's an interesting comparison between BH S50 and Waxoyl. Would be good to compare against Dinitrol 3125 too, as that has good reports. S50 isn't UV stable long term, and probably too soft for use in exposed areas anyway.

 

http://www.sxoc.com/vbb/showthread.php?287293-Flooding-sills-and-chassis-to-stop-rust&p=3253116&viewfull=1#post3253116

[nisfan]

Found this on www.rust.co.uk

 

http://www.rust.co.uk/filestore/Practical_Classics_Rust_Converter_Test.pdf

[Station]

Fucking rust eh?

 

Take a look at a nice Californian fuel tank:

 

 

And take a look at my shitty UK version:

 

 

Every single bolt is rusted solid. If I even attempt to to loosen one, the head will snap off. I'm going to have to drill each individual one out anyway. I've been offered a nice Arizona one for $200 not including shipping.

 

Also observe the American chaps floor. Why isn't an abundance of rust particles and 1 inch pieces of corroded bodywork?

 

Undo these screws, he says:

 

 

:z

[Jikovron]

I seem to notice that all the cars I like are made of sheet steel impregnated with rust particles or something like that and paint only where you can obviously see and poor paint at that , whereas the crap that I would happily watch being taken round the oval has been triple dipped,zinc coated, blathered all over the underside in plastic and painted 40 times inside the box sections

 

my own lazy technique is to merely keep the cars moving which dries out the chassis rails and sills etc , jet wesh out the underside seemingly the rust stays a sort of constant benign feature

of course it helps having a 100mile daily commute

 

once motors are laid up structural rot will always occur always in areas that aren't the usual thought of areas like top of the A pillars, and inside the roof

 

anytime you see the windows misted up on a car in a garage or parked somewhere ,,the same moisture is present inside all the box sections where there is next to no paint coverage, this only really dries on long drives and hot days imo :s

[Station]

I'm grateful I have a garage with free electricity. You know that thing will be getting heated.

They'll still rust though.

[dollywobbler]

Heat can actually speed up rust. A dehumidifier is what you want. 

[Uncle Jimmy]

Pretty sure monocoque car shells (Volvos for starters) were hot dipped. Heat isn't a problem if everything is hot, only if panels are partially heated. Sand blasting can cause distortion as only one area is getting hot.

[Des]

Mono shells are a big problem, since quality got left out of car building we're generally insulted with these poor substitutes lacking chassis, timber and bakelite with evermore components made of shoddy plastic. In fairness to the car industry they did take action from the seventies when the lack of resistance to rot became an embarrasment, almost all began dipping to ensure protection for the hidden areas, only that led to problems. Shell design had to incorporate drainage for all of those enclosed spaces to ensure quick and thorough draining so as not to delay production, now look under your average rustbucket and there's a Swiss cheeselike display of holes punched stratigically all over the shop which served the drainage purpose well, only now everytime the car is driven in the wet the 'enclosed' sections are fed a stream of nasty, salty, dogturd and roadkill rich wheelspray, blasts its way stealthly down the length of your pride and joy leaving a trail of moist shit, that's why your rear arches go along with the back ends of the sills. Closing off the holes would be risky as might create a damp trap, it's a whole fucking science thing to work out what to do, maybe pop rivit a bit of rubber flap in front of each opening to make airtight when moving, but then there's a risk of farty noises.

[mouseflakes]

but then there's a risk of farty noises.

 

That's a given when I'm in the car.

[nisfan]

I use to buy a shitter for a winter hack as a sacrificial piece to owning old chod. Ive now decided to run about in said chod as like has been said its not good sitting about (apart from the bluebird as that needs undersealed to fuck before it goes anywhere near grit). Ill be using an old polo as a daily until the stanza is welded, painted in waxoyl etc.

[Station]

Heat can actually speed up rust. A dehumidifier is what you want. 

 

I'll take the cars that have survived decades in a heated garage as fact it's better for it.

The garage isn't damp, it's just to dry off the accumulated water underneath (they're all jet washed on the weekend).

[Station]

(BTW, there's a dehumidifier in there already).

[mat_the_cat]

I wouldn't worry unless you're regularly driving a damp car into a heated garage. Heat will reduce the likelihood of condensation on the car, so coupled with a dehumidifier should be ideal!

 

Pretty sure monocoque car shells (Volvos for starters) were hot dipped. Heat isn't a problem if everything is hot, only if panels are partially heated

 

I still can't see hot dip galvanising being used for shells though. Things like the roof would visibly suffer from the heating and quenching, as stretched/curved areas may react differently to flat panels. It would also be difficult to get a good surface finish on the roof as the molten zinc is cooled. Plus you'd be left with drips from all the box section drain holes. Probably not impossible, but seems unlikely for a mass-production car when electroplating does a good enough job to last the design lifespan of the car anyway.