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rust
Posted: Sat Aug 26, 2006 6:35 pm
by rekitup
I have striped my moggy down to the chassie I cant aford to sand blast it so i will be wire brushing it and using red oxide primer. Is this sufficiant or is the a better way dealing with rust.
My moggy is an ex-gpo van from 1972 ( yellow will this mean it would have been on the telecomunications fleet)
Posted: Sat Aug 26, 2006 8:17 pm
by Onne
What have you done so far? Is the car all welded up?
I don't think there would be any problem if you do wire brush and RO prime it. Might even be a tad better that way, as it involves less force
Bringing all of it to the bare metal is certainly the best way of getting a good end result.
Posted: Sat Aug 26, 2006 8:30 pm
by minor_hickup
You could of course use a rust converter on any remaining surface rust. There's also the option of a zinc rich primer. I've never had rust come through well treated metal with a couple of coats of RO primer, even an old bull bar thats still in a bush hasnt gone rusty even though i painted it years ago.
Posted: Sat Aug 26, 2006 9:17 pm
by rekitup
The chassie is in good condition only one spot needs welding cant say the same about the body work tho need lots of pannels to complite wrote:What have you done so far? Is the car all welded up?
I don't think there would be any problem if you do wire brush and RO prime it. Might even be a tad better that way, as it involves less force
Bringing all of it to the bare metal is certainly the best way of getting a good end result.
Posted: Sat Aug 26, 2006 9:24 pm
by Onne
What sort of Minor is it? If you are talking about a chassis, you must have a LCV
Posted: Sat Aug 26, 2006 9:36 pm
by Packedup
I've been stripping to bare metal with a wire brush on a grinder, and spraying posphoric acid (with one of those garden hand sprayer things) on the metal first. When it's dried to a dull grey finish I've then been slapping red oxide on, followed by chassis black.
In theory that should keep any rust that hasn't been quite gotten rid of totally under control, but time will tell...
Posted: Mon Aug 28, 2006 9:52 am
by Robins
Has anyone tried Cilit Bang? Acording to the advert it simply cuts through the toughest problems like soap scum, bathroom grime and rust!!
If only it was that easy.
A wire brush is good, but a rotory wire brush on a drill is better as it really cleans the metal. I've never liked Red Oxide primer, fine on it's own and will last for years, but as soon as I put any sort of finish on top it always rusted. I like the under side of my cars the same colour as body so paint them the same way now.
Posted: Mon Aug 28, 2006 11:15 am
by nebogipfel
Has anyone any experience of "Rust Bullet"?
http://www.rustbullet.co.uk/shop/index. ... at&catId=3
If the comparative tests are to be believed nothing else comes anywhere near ("Product Tests" at the top of the page)
In the past I've always used Zinc rich primers - not with any great confidence
If you can get it blasted that has to be the best solution. The problem with wire brushing is it tends to polish the rust rather than properly remove it and of course does nothing for pitting. The paint used is then much less important.
I have to say I have always been sceptical of the magic properties promised by paints and have always argued that the end result is all in the preparation.
John
Posted: Mon Aug 28, 2006 11:56 am
by bigginger
nebogipfel wrote:
If you can get it blasted that has to be the best solution. The problem with wire brushing is it tends to polish the rust rather than properly remove it and of course does nothing for pitting. The paint used is then much less important.
I do have to say that a knotted wire brush in a grinder doesn't "just polish the rust". It can give good results.
Posted: Mon Aug 28, 2006 12:37 pm
by nebogipfel
Afternoon Andrew
Sort of; I do use a knotted wire brushes on a grinder and actually have a grinder with one on all the time. I tend to use it for small areas and brackets etc
That said, If you use it even on a flat easily accessible area and then blast that same area there is a world of difference in the surface of the metal. This I suppose is where a good rust inhibiting paint comes in.
Also, difficult corners and pits are virtually impossible to do properly with any sort of brush on drill or grinder.
You can do a reasonable job and it will help but you can't beat blasting in my opinion - especially if the chap doing it knows what he is about.
I know blasting can be expensive, difficult to get done, messy and in the wrong hands destructive but it is ultimately the best answer IMO.
John
Posted: Mon Aug 28, 2006 8:16 pm
by bigginger
Agreed, especially over "awkward corners". Turning it on the side can help with pitting to some extent, but blasting/acid dip are FAR superior. If, however, all you have are drills/grinders, it's the best of the worst choices
Posted: Mon Aug 28, 2006 9:16 pm
by Packedup
bigginger wrote:nebogipfel wrote:
If you can get it blasted that has to be the best solution. The problem with wire brushing is it tends to polish the rust rather than properly remove it and of course does nothing for pitting. The paint used is then much less important.
I do have to say that a knotted wire brush ib a grinder doesn't "just polish the rust". It can give good results.
I've got a large-ish cup brush on the grinder, and it doesn't just polish the rust, it also fires sharp wire into my legs at high speed too if I crank the power up (got a variable speed one for this very reason).
Though it does do quite good job of removing the rust too. Not as good as a knotted one I suppose, and nothing like as good as blasting or dipping, but there's no way I can afford either of the better options, so it's stripping, brushing, treatign and painting for me unfortunately
Posted: Mon Aug 28, 2006 9:46 pm
by alex_holden
Packedup wrote:it also fires sharp wire into my legs at high speed
Have you tried wearing trousers?
Posted: Tue Aug 29, 2006 8:41 am
by chickenjohn
I use my lowest power grider for the wire brush- either a cup brush or the radial one . Seems to work better funnily enough with the cheapie Blackspur than Bosche or Focus one.
if metal is deeply pitted, you are better off cutting it out and neatly butt- welding a patch in as its thinner and weakened by being pitted. Trying to weld to pitted car bodywork - eve completely cleaned up- you are going to blow holes. Wire brush on grinder is great but more for surface rust removal.
Posted: Tue Aug 29, 2006 10:31 pm
by markattard
I use Wurth Rust converter, it is applied with a paint brush or sprayed and turns rust to black. It has been tried and tested on my cars for more than three years now and on my well bucket metal handle, all still rust free
Posted: Wed Aug 30, 2006 9:27 pm
by minor_hickup
I've never liked Red Oxide primer, fine on it's own and will last for years, but as soon as I put any sort of finish on top it always rusted. I like the under side of my cars the same colour as body so paint them the same way now.
How odd, I've always used RO primer as a primer to hamerite because it covers better and hamerite seems to cover better over RO primer.
Posted: Wed Aug 30, 2006 10:00 pm
by alex_holden
minor_hickup wrote:How odd, I've always used RO primer as a primer to hamerite because it covers better and hamerite seems to cover better over RO primer.
Better than what? Hammerite anti-rust primer?
Posted: Wed Aug 30, 2006 10:39 pm
by minor_hickup
Hammerite on its own, as you don't need a primer. I don't think much of their anti rust primer, it just seems like grey hammerite to me just a bit thinner in a difficult to use can.
Posted: Thu Aug 31, 2006 12:13 am
by Packedup
minor_hickup wrote:Hammerite on its own, as you don't need a primer.
Oh you do. And you need a topcoat of something that isn't Hammerite. Then you need to make sure the lid is firmly on the hammerite can, put it in a box, and drive it to the tip.
Practical Classics did a test a few years ago, and Hammerite didn't exactly do well. In fact, it did extremely badly. It might be OK for ironwork if you don't mind touching it up every few years, but using it straight onto bare sheet metal didn't give good results - You'll probably find if you're doing OK with it it's because of the primer you're using
Posted: Thu Aug 31, 2006 9:16 am
by alex_holden
Can't say I've had much of a problem with Hammerite primer and gloss black topcoat, and I've used quite a lot of it over the years (though the primer used to be dark brown and is now grey?). So what paints did better in the test?