Rust treatments?

[dean36014]

So been a long time since I've messed about with car bodywork. Want to rust treat a few rust spots on the Suzuki, and wire brush up and treat the boot floor and a few little other places underneath. Can remember years ago buying little bottles of rust treatment that promised the earth and achieved diddly squat, so whats good, and cost effective today?

For the underside I will eventually re stonechip the floor using a compressor and shultz gun, but thinking of using this first,

http://www.frost.co.uk/automotive-paint-coating-electroplating/automotive-paint/por15-paints/por15-semi-gloss-black-rust- prevention-paint-473ml.html

Then a further coat over the stonechip when dry. Is Frost's the only place you can get it or is there anywhere cheaper?

Thanks in advance.

 

[sierraman]

I'd take the rust back to metal with a grinder, put some rust converter on such as kurust. Then, if it's a hidden area such as floor, paint on 2-3 coats of zinc anti rust primer by hand, then a few coats of shutz. It's all in the preparation. Fuck up on that and the rust will be back. I mean you can get some top quality rust converters and paints but realistically unless you are embarking on a restoration it simply isn't worth it. £15-20 should've plenty to buy the materials for the whole job.

 

As a side note I wouldn't attempt this sort of job at this time of year, it's far too damp and cold. Mid summer is your best bet.

[garbaldy]

Kurust is shit.

[rainagain]

Rust Grip by AV coatings is excellent. 

[Split_Pin]

Previous convos on here say Bilt Hamber is good.

[DVee8]

I used a Hammerite rust remover on the mgf worked a treat.

Looked somthing like this.

 

[Royale80]

I used Bilt hamber Hydrate. Used a flap wheel to get rid of the rust-used the Hydrate and painted (brush) 2K Epoxy Primer. Seems to have done the trick.

 

Steve

[Des]

Vactan is a good converter, works as good just lazy arsed slopped on as the others will with a heartbreaking amount of effort and palaver. It leaves a coating that sticks fairly well, but not to the non rusty bits, so worth batting over with a scotchbrite or something, then a splash of etch primer should keep the rot at bay for many weeks.

[mercrocker]

Second on the Vactan.....My test horse shoe is still clean nailed up on the shed.  More importantly, the Cowley floor is still good after 18 months of driving it round with no carpets.  As Des says, its the most user-friendly stuff I have come across - no washing off, no buggering about with waiting for the 3rd full moon after lent to recoat it within a 6 minute window etc etc... 

 

I have brushed it on the Cowley grille which is painted steel and quite badly pitted without even a primer on top and the metal is still black. 

 

Anything branded Hammerite just seems like rhyming slang nowadays, I use Bilt Hamber zinc primer and POR-15 chassis paint.  

 

Underneath the Cowley (which was bare metalled a couple of years ago) I have an American coating called Lizard Skin, applied by a friend of mine whilst the car was on a roller.  He wanted to use the car as a test for it, we haven't top coated it to see how it holds up and so far, so good.  Very expensive and needs to be sprayed on but has not abraded anywhere yet.   Its going up on the four post tomorrow so I will see how it is.....

[rainagain]

 

 

Anything branded Hammerite just seems like rhyming slang nowadays, I use Bilt Hamber zinc primer and POR-15 chassis paint.  

 

 

I read somewhere that they had to remove the stuff that makes it work due to EU regulations, same reason why I bought some Humbrol paint recently and it was like water. In my last job we had a lab where they used do forensic failure investigation on things like big valves and pipework. They used to have a really strong acid that would remove rust from steel as your watched. It was seriously strong and had to be used in a fume cupboard, I did think about nabbing some but after speaking to the lab techs it I decided against it as I didn't want to risk removing my flesh with it. 

[sierraman]

The Bilt hamber stuff is £16 an aerosol!!! Bloody hell!

[cros]

I'm with Merc. and recommend testing rust treatment on a horseshoe first, but the impatient fuckers will insist on a gallop before its dried.

[sierraman]

Maybe mercrocker was just lucky I don't know.

[brickwall]

Big bottle of phosphoric acid....3 quid

[mercrocker]

The Bilt hamber stuff is £16 an aerosol!!! Bloody hell!

 

I know, it ain't cheap but the cans are quite big and spray well down to last dregs with only minimal pre-warming.  I think its better value than Waxoyl even though its dearer.

[twosmoke300]

POR 15 is bloody good paint for stopping rust coming through . Not uv stable so needs a top coat tho . Having said that I've used it on its own for years and it's been fine

[sierraman]

A lot of the cars I've had I've bought for a grand and under, where waxoyls worked for me has been its staved off the rust for a few years, it's cost me £20 for 5 litres and saved me probably several times that in welding. A lot of where it gets a bad reputation is where people have sprayed it into some already rotten sills, with that pump thing that gives a vinegar strokes worth of effort, in shit weather with minimum preparation.

 

Incidentally unless you are absolutely sure the sills are rot free internally and you can apply it at pressure into the box section, then don't do it. The poor fella who ends up welding patches on the sills when you've done a half arsed job, won't thank you one bit when he's trying to weld the fucker up and there's waxoyl all over the shop as he's trying to weld.

[dollywobbler]

That was the stage I got to with the 2CV. Once I could see it was going to need work, I thought filling bits with flammable wax wasn't a good idea. I did squirte stuff into sills and box section, but it has been quite determined to rust.

[rainagain]

Big bottle of phosphoric acid....3 quid

Where can you get that from?

[DaveAspley]

FLAG rust convertor from Toolstation. £18 for a tin that should do 3 cars top to bottom. Brought the surface rust back to metal in a few hours in the footwells of my car. Can be left and overpainted once dry, going to spray it into the chassis rails and then follow up with tetrosyl chassis coat.

[sierraman]

How badly do things go rusty though? I've had welded repairs covered with some zinc primer and a few coats of shutz and they've lasted years. So long as it's had metal cut out and replaced it should outlast the rest of the car.

[alf892]

Where can you get that from?

Jewsons and the like...........Brick Cleaner

[dollywobbler]

How badly do things go rusty though? I've had welded repairs covered with some zinc primer and a few coats of shutz and they've lasted years. So long as it's had metal cut out and replaced it should outlast the rest of the car.

 

Oooh! I can answer that!

[mat_the_cat]

How badly do things go rusty though? I've had welded repairs covered with some zinc primer and a few coats of shutz and they've lasted years. So long as it's had metal cut out and replaced it should outlast the rest of the car.

 

Depends whether the repair is just to get you through the next few MOTs, or whether you plan to keep the car for 10, 20 years in the future...

 

Another point to bear in mind is that welds *tend* to rust faster than the surrounding steel for a variety of factors - porosity, contamination, the way the steel recrystallises, water traps etc. So the protection afterwards has to be equal or better than the factory coating just to last a similar amount of time to the original! Added to that the fact that any coating which dries by evaporation (i.e. most of them available to DIYers) has to leave some level of porosity for the solvent to evaporate through, and is it any wonder why welded repairs don't last?

 

POR15 hardens by reacting with moisture, so shouldn't suffer porosity in this way. However I haven't had long term success with it when used on shot blasted parts, which started to rust after 10 years storage in an unheated but dry garage. Others have had more luck so there may be some other factor I'm not aware of...

 

As for chemical rust treatments, I'm not a fan of converters (i.e. the ones which turn rust to a black inert oxide) as there is a danger you can leave an unconverted layer of rust underneath. Try scratching the black oxide with a knife after treatment - if you get any red rust visible you haven't got it all!

 

Chemical rust *removers*, which take rust back to shiny steel, are in my experience no different to physically grinding away the rust - but less effort although slower; think in terms of days on pitted rust. Personal preference for removal is to get most of it off mechanically, then use a chemical remover e.g. BH Deox to get the remaining pits and work into seams which would otherwise remain rusty.

 

I'm doing a trial on 'cold galvanising' rusty metal, if people are interested?

http://autoshite.com/topic/18079-disco-fever/?p=760258

[3VOM]

POR15 hardens by reacting with moisture, so shouldn't suffer porosity in this way. However I haven't had long term success with it when used on shot blasted parts, which started to rust after 10 years storage in an unheated but dry garage. Others have had more luck so there may be some other factor I'm not aware of...

 

I'm sure I just watched a car renovation video where the guy said he uses POR15 but you have to etch prime the surface first. Peter Anderson (the Aussie guy) maybe?

[mat_the_cat]

If I remember rightly the instructions said NOT to apply over other paints, as you wouldn't get the benefits. I'm actually inclined to give it another try, as many other people whose opinions I trust have recommended it, I'm wondering if I applied it too thinly perhaps.