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Galvanised Chassis
Tim Watson - 9/8/10 at 10:09 PM

Hi,

My mate does up Land Rovers and has had one of his chassis galvanised. Says the chassis will last a LONG time.

It got me thinking, has anyone on here done that with their car? Would it solve the problem of rust where aluminium meets steel when driving on previously salted roads?

And on a side note, would it add significant weight to the chassis?

I'm saving up for a Raw Striker chassis, want to take my time and get everything right as I slowly build the car and so thought that could be a good investment.

Tim


Dangle_kt - 9/8/10 at 10:12 PM

others will know much more than me, but I beleive there is a danger of the chassis warping in the hot dip.


nitram38 - 9/8/10 at 10:14 PM

Galvanising is a pain!
You cannot galvanise a sealed box section so you have to drill opposing holes in all the chassis sections so when dipped, galv can run in and out of the box. We are talking 10-12mm holes.
Also galv can become trapped inside sections adding serious weight and also increasing the cost to you.
They weigh your chassis before and after and charge for the weight added!
You will be better off using a decent paint or using a cold galv spray paint.


JF - 10/8/10 at 04:31 AM

For a relatively simply landy chassis it's easy. Two runners and a few crossmembers. But spaceframes like used in sevens are almost impossible to do right. Way to many holes to drill and difficult to get the stuff out again afterwards. If you don't drill enough holes some tubes/box sections might/will explode.

And as you have to drill a minimal of 2 big holes in every single box section you are seriously weakening the chassis, or risk it turned to scrap.

So no... stick to good paints, primers and sealants...


adrianreeve - 10/8/10 at 05:46 AM

I used to work at a galvanisers, and saw then ruin a very expensive 1950s Ferrari spaceframe race car chassis with distortion. Molten zinc used in the process is 460 deg c, so very easy to distort stuff. Also, as has been mentioned, sealed section is a no no, so strength is reduced by drilling every tube.

I wouldn't!

Cheers

Adrian


adrianreeve - 10/8/10 at 05:46 AM

I used to work at a galvanisers, and saw then ruin a very expensive 1950s Ferrari spaceframe race car chassis with distortion. Molten zinc used in the process is 460 deg c, so very easy to distort stuff. Also, as has been mentioned, sealed section is a no no, so strength is reduced by drilling every tube.

I wouldn't!

Cheers

Adrian


mad4x4 - 10/8/10 at 07:04 AM

Look for a product called ZINGA (www.zinga.co.uk) and see if there is a local agent to you. I had my chassis done with this and 6 Years on not a spot of rust.... Cost about £100 to get it done


Bluemoon - 10/8/10 at 07:25 AM

You could think about hot zinc spray. The zinc is sprayed on, it works really well without distorting the chassis; I wanted to do this but need some welding done latter so it was not really an option... This process is as good as hot dip but without the heat distortion or needing holes drilling. When I looked at this 5 years ago the cost was not much more than powder coating (about £300 at the time).


Tim Watson - 10/8/10 at 08:00 AM

Cool, thats a no then . I'll look into those other products though cos they sound useful.

Tim


omega0684 - 10/8/10 at 09:02 AM

Tim you want steel frame and then powder coat.


Bluemoon - 10/8/10 at 11:34 AM

quote:
Originally posted by omega0684
Tim you want steel frame and then powder coat.


Probably... That's the powder coat is the "normal" way (but you can do it your way if you know what you want..)..


MikeR - 10/8/10 at 12:58 PM

My experience was speaking to a professional powder coating company when i was looking at doing my chassis, they "confessed" that powder coat isn't really designed for outside use and they wouldn't recommend it for long term protection.

(this is from talking to BG Penny in Coventry who advised me that they would do it (with preferably a zinc coating underneath) but would recommend that on top of the zinc its painted with a few layers of paint instead.)

I have to admit this confused me as another company in coventry advertises that they do car parts specifically! I guess saying I spent 10 years building the chassis had them thinking i wanted it to last 50+ years hence their comment.

[Edited on 10/8/10 by MikeR]


procomp - 10/8/10 at 03:12 PM

Hi

A very good etch primer either by hand or spray painted. It can be touched up very easily when stone chips appear and they will appear if you drive it.

Cheers Matt


coyoteboy - 10/8/10 at 04:35 PM

Had very good results with galvafroid on marine boat trailers, lasted a good 10 years left out in the rain and annually immersed in the sea off and on for 2 weeks. Lasts longer than wheel bearings in the same trailer!

It is rather agricultural in appearance though, very thick paint so leaves brush strokes if you're not careful and it's matt silver.

[Edited on 10/8/10 by coyoteboy]


wilkingj - 11/8/10 at 09:55 PM

Whatever you do, Shot or Sandblast the chassis FIRST.

The finish is ONLY as GOOD as the Preparation.


Benonymous - 12/8/10 at 11:09 AM

I'm another -1 on the powder coating. I had a 7 style chassis done in powder coat and it was over baked. I didn't find out for a while but it made the plastic very brittle. It was flaking off all over the chassis I used a 2 pack paint to try to repair it but the task was hopeless. i would recommend a good, gooey enamel or even Hammerite. These products stick like the proverbial and can easily be touched up or repaired. Powder coating is good for small parts like brackets and such but when you think about it it's a lot of work/expense and all you're really trying to achieve is a nice even finish and no corrosion.


kb58 - 12/8/10 at 01:23 PM

I'm sorry to hear that powdercoating didn't work out for you. Perhaps in addition to overbaking it they used the wrong powder? There are probably a dozen different kinds, and each is best at in a certain environment. In any case, saying that a process wrongly applied is no good isn't proof that it's defective as a whole. Thousands of cars have been coated without issue.


mrwibble - 12/8/10 at 03:09 PM

can i interest you in a can of dinitrol 3125

cheapest on the bay at the moment ?
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=220649654591&ssPageName=STRK:MESELX:IT

shameless i know


interestedparty - 12/8/10 at 04:48 PM

Powder coating a quick and simple (therefore cheap) option for manufacturers. As long as it looks ok for a couple of years that's all most of them are bothered about.

I would never specify powder coat even if I could afford to buy a complete kit.


Bluemoon - 12/8/10 at 05:24 PM

quote:
Originally posted by interestedparty
Powder coating a quick and simple (therefore cheap) option for manufacturers. As long as it looks ok for a couple of years that's all most of them are bothered about.

I would never specify powder coat even if I could afford to buy a complete kit.


Ditto, that's why I used acid etch+topcoatx3, if you use radiator roller you can get a good finish.

If I was to paint my chassis again I would use acid etch, then normal external gloss under coat and a external gloss top coat as it remains flexible.

I would also choose a color that shows stress cracks like gray..... I might even do this over the top of the hot zinc spray (the etch primer will stick to this).

Dan


scootz - 12/8/10 at 05:42 PM

I use an acid-etch and then epoxy-mastic.

A bit of faffing about, but do it right and you'll reap the rewards. I absolutely HATE it when the chassis starts to get tatty!


Tim Watson - 14/8/10 at 08:22 AM

Going back to one of my original questions, with the right treatment (such as mentioned above) would this mean that you were confidently rust-proofing where the chassis meets the suspension - i.e. salty water where steel meets aluminium? I would be opting for newly fabricated suspension bits as opposed to Sierra/Capri.


scootz - 14/8/10 at 08:54 AM

It'll do it just as well as anything else this side of silly-money technologies!


dinosaurjuice - 14/8/10 at 09:11 AM

seems like a lot of you on here have had experience of bad powdercoaters. Ive used a couple in midlands and now ONLY use Redditch shotblasting and powdercoating. They always shotblast first, and achieve a near perfect finish everytime. The finished coating can be attacked with a file, pliers, grinder anything and it behaves like its part of the metal. None of this flakey nonsense you get from cowboy powdercoaters.

So, adding to the wilkingj's comment of preperation, its also definately worth going somewhere that actually knows what there doing. although it will cost more

just my opinion


interestedparty - 14/8/10 at 10:27 AM

quote:
Originally posted by dinosaurjuice
although it will cost more




Any idea how much for a chassis?


Strontium Dog - 14/8/10 at 10:48 AM

quote:
Originally posted by MikeR
My experience was speaking to a professional powder coating company when i was looking at doing my chassis, they "confessed" that powder coat isn't really designed for outside use and they wouldn't recommend it for long term protection.




There are primarily two types of powder coat, Epoxy and Polyester. You need to use the right one for external use. Epoxy flows out better and gives a superior finish but does not like being outside in the elemrnts. Polyester is more orange peely but is more suited to external use.

Make sure your powder coater is using the right powder for your application


dinosaurjuice - 14/8/10 at 01:42 PM

quote:
Originally posted by interestedparty
quote:
Originally posted by dinosaurjuice
although it will cost more




Any idea how much for a chassis?


I paid £300+VAT for my MEV Rocket chassis, worth every penny.

Piccy:


will


Valtra - 14/8/10 at 09:44 PM

powder coat seems fine to me still looks good after several years, but car is not actually outside that much of the time . As said before you need good prep., and FFS don't brush paint the chassis, 9 times out of 10 it looks pants. I've seen dozens of quite high spec well built cars ruined by brush marks and once the car is built you are stuck with it unless you strip the whole car down and start again , so unless there are NO exposed bits at least spray it . Having said all that, Smootherite can be brushed quite well but it's too big a risk , 4 or 5 rattle cans could easily do a whole chassis if you don't have access to a compressor


JF - 15/8/10 at 10:32 AM

Yeah but a layer of spray paint (especially rattle can) is really easely damaged. Personally I'd want a more durable finish.

I know a guy that had his BMW motorbike bedliner sprayed. Quite rough matt look, and just as durable. He had the frame, tank and panels sprayed. And it is developed for rough outdoor use in pickup trucks.

From what I've heard it ain't cheap, but to me it would be worth considering.


Neville Jones - 15/8/10 at 12:01 PM

After years of trying all sorts of methods. the best I've come up with is as follows:-

Degrease meticulously to a very clean condition.

Apply zinc phosphate primer, 2 coats letting fully dry in between.

Top coat of 2 pack paint, preferably a polyurethane, as it doesn't get as hard and brittle as the others.

I've tried Galvafroid, and it's fantastic, but doesn't tend to 'stick' to the base steel. If chipped it reveals a bright and shiny base, but it does tend to chip easily, independant of what's on top.

My local powder coater will not coat bare steel, he insists on zinc passivate underneath first. He says this is from past experience, and too many jobs returned 6 months on with peeling due to rust formation underneath.

Marine epoxy mastic type paints are great, after all they keep big ships rustless, but are not too user friendly, and are meant to be applied fairly thick, which tends to a poor finish.

Cheers,
Nev.


Valtra - 15/8/10 at 01:26 PM

Frosts catalogue has a whole range of different paints (if you must) that look suitably tough . not cheap , but as the saying goes don't spoil the ship for a hap'eth o tar.


metallisation - 22/9/10 at 03:41 PM

Hi All

I work for Metallisation Ltd who are a thermal spray equipment manufacturer.

Thermal spray was mentioned above as an alternative for galvanising and much of what was said above is correct with regard to long term protection, and thermal spray not giving the same distortion problems which you may get with galvanising.

If anyone wants any advice on this process or the equipment should you wish to set up yourselves, or for companies who may be able to carry out this operation for you in your local area then please do not hesitate to contact me on the following email or phone and I will try to assist

07595 651643
iainblacklock@metallisation.com

p.s. you can also spray other metals such as copper, bronzes, brass, tin/zinc (which polishes back really well) for decorative finishes which can then be polished back and aged if necessary - just an idea for you :-)

Regs

Iain

[Edited on 22/9/10 by metallisation]