Process for treating rust..?

[G-Bear]

I'm sure this is as common as 'what G-max setup should I go for'. However I've been sat here curled over my laptop for a while now, reading through threads and feel rather bamboozled by it all.

I have some rust in my boot that I want to address. Its mainly down in the pockets along the seam of the rear panel. I think ultimately/eventually; it'll be a cut out and weld new steel in job.

But for now I would like to test out some products/processes.

I currently plan to...

Grind back as much of the rust as possible, with a flat disc or knot brush.

Clean the area with Bilt Hamber surfex-HD
http://www.bilthamber.com/surfex-hd

Treat rust with Bilt Hamber deox-gel.
http://www.bilthamber.com/corrosion-treatments/deox-gel

Then us a etch primer.. any suggestions of brand?
This stuff any good... POR15 Self Etching Primer
http://www.frost.co.uk/automotive-paint ... 426ml.html

Then what primer would people suggest?
POR15 Tie Coat Primer?
http://www.frost.co.uk/por15-tie-coat-primer-paint.html

This stuff looks might it may be better suited for under the car..
http://www.paintmarine.co.uk/jotun-jota ... r-40-p.asp

Then I was going to use 3m seam sealer.
http://catalogue.3m.co.uk/en_gb/gb-aad/ ... er%7E08537

Then a top coat and lacquer (The cars Sterling Silver).

Just interested to see what peoples thoughts were..

Sorry for all the links, it just seams like a minefield and wanted to narrow it all down.

Cheers

Greg

[polsta]

Take and post some pics, particularly of the rear panel join you mention to show exactly where and how much,with them sort of areas where there are lips/flaps you need to ensure there's no rust left right in/under if your talking grinding down treating and seam sealing, to then let rust fester hidden away, what's the rest of the rear panel/valance and joins drain runs etc like ? And around the plate lights etc ? As with the pocket areas you mention its all that same area if the rest of the panel is iffy in areas it might be better to do a full new rear panel job and be done with it, or if its all real nice then address the said areas

[capri_rob]

Your problem Greg unless you are VERY lucky is that as soon as you go anywhere near it with a knot-brush you wont have anything to paint onto.

I understand the bilt-hamber stuff is very good but if its an area thats hidden I wouldnt worry too much about silver top coats unless its a concours car and you're intending on pulling the carpets out at shows

When I did mine a couple of years ago on the areas that had new metal welded in and anywhere that had genuine non structural surfac corrosion I just used 2 or 3 coats of black smoothrite and then caked it in waxoyl. Its still all good.

[G-Bear]

Thanks for the replies gents..

Crikey I think I stayed up too late reading up on this... I dreamt about rust and paint all night..

As I said originally, I'm pretty sure I'll be cutting out most of this and letting new steel in eventually. But if I do this, I'm going full hog. And currently don't have the time to spare, plus the car is in use as a daily at the moment. The boots striped to replace some shot rear top mounts.

So really was interested to see how some products worked.

..lips/flaps you need to ensure there's no rust left right in/under if your talking grinding down treating and seam sealing, to then let rust fester hidden away, what's the rest of the rear panel/valance and joins drain runs etc like ? And around the plate lights etc ? As with the pocket areas you mention its all that same area if the rest of the panel is iffy in areas it might be better to do a full new rear panel job and be done with it, or if its all real nice then address the said areas

I think its a new rear panel and the job done wasn't that great. The rust set in along the seam, where rear rail meets the rear panel. I checked where the the floor pan of the boot meets the era panel and that seems okay, although I second check wouldn't go a miss. But you're right, it's more than likely to have got in right under the lip, where perhaps grinding, rust treating may not have much effect right in deep. I just wanted a quick fix (no such thing with rust) to slow it down until I do it properly when the weathers better.

I understand the bilt-hamber stuff is very good but if its an area thats hidden I wouldnt worry too much about silver top coats unless its a concours car and you're intending on pulling the carpets out at shows

Cheers Rob. After a bit more research last night I'm swaying to an epoxy primer of some kind after treating the rust properly. As for the silver top coat, I just fancied matching it all, but overall just to seal the primer.

I'll get some pics up tonight hopefully. Thanks again.

[Gavla]

Bilt Hamber all the way!

Once treated you can always try a can of Eastwoods Rubber / Rust encapsulator...couple of thin coats should do the trick!

[polsta]

I've never used BH products, but ..lol....see if any of them have the fertan properties in the sense that - when used in such areas you just want to halt rust in that under lip area you can't quite get in to - if you use BH products etc to get rid and cure, if you put fertan in afterwards then seal it all, fertan lays dormant I gather forever, and can kick in if any rust starts again - so when used in that lip/join situation it may be beneficial once you've done what you can , to use some of that to fill the join and lay dormant and be a good long term preventative measure, or see if any BH products do that, you can seam seal and paint over the fertan too, its beneficial stuff not in terms of real rust removal but to let lay in nooks and crannies and lips and joins like that

[G-Bear]

I was thinking of throwing some Fertan in after the Bilt Hamber gel. Like I said, Its a good opportunity to try a fews things out.

Didn't get any time for the car today, so hopefully shall have some pics up tomorrow.

@Gavia - Cheers for the heads up, have been looking at Eastwoods products too... To be honest I've lost telling my arse from an aerosol can in the last few days, reading up on various, primers, rust treatments etc. But shall have another review of it all and throw Eastwood's into the mix again.

[Jozi]

What you have in your op looks good enough to me. I've never used por15 though each to their own but it gets mentioned a lot. Instead of going at it with a knotted wire wheel use a cupped wire wheel like this: http://thumbs2.ebaystatic.com/d/l225/m/ ... stzmOA.jpg

I found the knotted ones to rip through metal where as the cupped one above will not remove old primer unless you leave it on it a little longer. Once the lose rust is lifted let the deox gel do it's thing, if your leaving it for more than a few hrs/days, cover it with some cling film. This way it won't go hard as quickly and makes it easier to clear it away, when it's gone black it's hard and a prick to get away.

[Morat]

POR-15 sets like rock and seals out moisture. The claimed advantage is that it doesn't leave a porous finish like most paints which rely on evaporating solvents. It cures on contact with moisture rather than "setting" as solvents evaporate. The problem being that solvents leave through tiny holes which are left behind for moisture to penetrate over time. Or so they claim....

POR-15 is sensitive to prep, and it doesn't like smooth clean steel because it won't bond and there have been cases reported (on the internet, mind!) of it peeling off in sheets when people haven't keyed the surface properly.

I've used it, and been impressed.

For my wife's E46, I wanted something that would prevent rust on a clean but second hand front wing. Bearing in mind POR-15 not really liking clean steel I used BH Hydrate-80. It went on and behaved as expected, darkening over the course of 24-36 hours with no sign of it falling off. I'll have to have a peek under the wing and see how it is doing. It's been on there about 8 months IIRC.

For something that is already rusty, I'd go with some POR-15. Slap it on there with a brush you don't want back Just bear in mind that if there's moisture coming through from the other side, the steel will rust away and leave the POR-15 behind! But I can't see that being different for any coating. You need one good, dry side or you're screwed.

[Demlotcrew]

Does POR-15 have zinc in its arsenal?

[magpie]

if it's surface rust just sand it by hand then treat with captain fertans magic remedy ,let it dry then primer and paint .

[Morat]

Does POR-15 have zinc in its arsenal?

Not in the paint, but they do have a product called "Metal Ready" which is used to prepare a surface for POR-15.

More details here: http://www.por15.com/POR-15-FAQS_ep_61.html
I'm not an expert!

[Demlotcrew]

See I think I would be using something like this

http://www.ebay.co.uk/itm/400609412413? ... 1423.l2649

Not had much luck with POR or Bilt Hammer.

I actually also like this product for killing off rust.

http://www.ebay.co.uk/itm/Jenolite-Rust ... 461a84178c

But something tells me the dilution of acid in Jenolite has changed somewhat as small splashes on my arm dont sting anymore

[Brianmoooore]

There are two distinct types of chemical rust treatment available. One type totally encloses the existing rust, forming a barrier between it and subsequent paint, and the other uses phosphoric acid to change red iron oxide into paintable black iron oxide. Both work, but obviously the best solution is the second one.
For any parts that are small enough to be immersed in water, electrolysis is the simple and cheap solution.
Zinc paints aren't a treatment for rust as such, but an enhanced method of preventing rust, based on a similar electrical process to electrolysis. Steel won't begin to rust until all the zinc close to it is used up.

[Demlotcrew]

Do you agree that using a Zinc primer is better than using one that doesn't contain any?

[Brianmoooore]

Definitely, in places that are likely to rust/paint get damaged. It's a rust preventer not a rust curer.

[Demlotcrew]

So to the OP.

I would use something like Jenolite to neutralise the rust. Then cover with a Zinc primer.

HTH

[Jozi]

Brian, what is used in the water for electrolyses? I've tried it using two different powders but neither seemed to be doing much. I tried it with the diff, which as it turns out lets water in when there's no gasket :/

[Brianmoooore]

Ordinary washing soda (sodium carbonate) is the electrolyte for rust removal. It's purpose is to make the water conductive, and doesn't actually participate in the rust removal.
Connect the negative lead to the object to be derusted, and the positive to a number of scrap iron or steel anodes around the object and adjust the current that flows to around 1 - 2 amps.
If the diff keeps oil in, it should keep water out, but I'd always recommend draining the oil from a diff. after treatment. The solution isn't corrosive, so a small amount of water inside a diff. for a couple of days insn't going to do any harm.

[Jozi]

I must try it again, I got two different cleaning things that contained sodium carbonate but maybe the battery + charger wasn't delivering the right current. Diff has been without oil for a long time, I might grease up the gasket area a little and try it again.

[G-Bear]

Thanks for all the input. Has given me loads more to look up. I'm definitely leaning towards some form of epoxy primer. I wanted zinc in the primer either way.

Demlotcrew in what way have you not had much luck with Bilt Hammer? I noticed they have a epoxy primer with zinc in it.

Anyway also as promised.. in the link below are some pics, just scroll to the bottom and fill your boots..

http://www.e30zone.net/modules.php?name ... c&t=225407

[Jozi]

The bilthamber gel is ideal for the edges around the tailgate, slap it on and with some clingfilm over it it will stay there and do it's thing, might need a 2nd doing but I got a very nice clean finish from mine once done.

[G-Bear]

The bilthamber gel is ideal for the edges around the tailgate, slap it on and with some clingfilm over it it will stay there and do it's thing, might need a 2nd doing but I got a very nice clean finish from mine once done.

And that was enough Jozi? Just I thought it may have worked its way deeper.

[M3Jim]

You won't be disappointed with Bilthamber. Give them a call and ask for pete, he really knows his stuff and will be happy to talk through your needs and advise on the best products to use.

[Brianmoooore]

Rather than playing around with all this branded, overpriced, ultra dilute, health and safety and tree hugger approved stuff, get onto ebay, and type in phosphoric acid.

[Demlotcrew]

Exactly!

The hydrate 80 just didn't convert any rust at all! You could still see all the iron oxide under the treatment.

Jenolite starts working right away, you can see it fizzing as soon as it goes on.

Not used any of the other bilthammer products.

[Gert_8]

Exactly!

The hydrate 80 just didn't convert any rust at all! You could still see all the iron oxide under the treatment.

Jenolite starts working right away, you can see it fizzing as soon as it goes on.

Not used any of the other bilthammer products.

Just out of interest, is the Jenolite product brushed on, or can it be sprayed? Also does it act like Polsta says Fertan does, i.e lie dormant?
Thanks.

[Demlotcrew]

Its brush on, not sure if it does lie dormant or not, I simply brush it on, leave it to remove all the rust and clean the metal ready for zinc primer. If you leave it on it simply goes white and keeps the rust from coming back, but I don't think this is the best way as it might not key the next layer too well.

I recently used some acid on these parts, come out very well.

I should have taken a before photo! But they were quite rusty

[Demlotcrew]

Found a before!

[Jozi]

The bilthamber gel is ideal for the edges around the tailgate, slap it on and with some clingfilm over it it will stay there and do it's thing, might need a 2nd doing but I got a very nice clean finish from mine once done.

And that was enough Jozi? Just I thought it may have worked its way deeper.

No way to tell really but I hope so.

[Gert_8]

That is impressive - especially on removable parts. I can see a problem for G-bear using something like this to access the areas he wants to work on, do you think?

[Demlotcrew]

Well its a gel, so no problems in getting it vertical surfaces. I think maybe the Hydrate 80 needs heat to work and is only good for the summer months?

[G-Bear]

A big tub of phosphoric acid sounds inviting. Had a very quick read into ways of thickening it up into a gel form so it holds on top of the rust and to not dry out.

Worth a test.

[bdx]

Phosphoric acid is milkstone remover

Go to your local farm supply shop and ask for milkstone remover.

Approx £10 for 5L

Its used in the dairy industry to remove milk from pipes etc.

[Brianmoooore]

Phosphoric acid is milkstone remover

Didn't know that - and I frequently work in farm dairies, with large cans of the stuff around!
Just might have to take an empty plastic container with me the next time I go to one.
For comparison, Jenolite is about 2% phosphoric acid, milkstone remover is 50%+.

For small removable parts I'g still recommend electrolysis though.