gruntus

Galvanised bulkheads Yes or No!!

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Ok so I keep getting conflicting opinions with regard to galvanising D90 bulkheads.... :unsure:

I am going to fit a new bulkhead and would like to get it galvanised.

One minute I am told it is okay the next I am told it shouln't be done but "can't remember why..."

Anybody out there with experience of this?

I would have thought a new bulkhead would stand up to the effects of any distortion whilst being zinc plated however I also know that all the paint has to be off the item before dipping in zinc (how do you bead blast the insides of the box section? :unsure:

The other possible reasons for not doing it would be either the zinc flaking off or the paint not taking to the zinc (I know an etch primer should overcome this).

Any of you guys done this before and give some advice?

As always your help is appreciated :)

Regards,

Grant

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I've only ever heard that it could distort due to the heat, but if Ford can galvanise an entire Focus then I don't see why a decent galvansier shouldn't be able to do a bulkhead - perhaps pre-heat it or something? I've seen galv ones for sale before so people have done it.

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my local Galving place are dodgy enough when it comes to chassis let alone bulkheads.

You do have significant risk of warping mind- you would do well to weld some strengthening bars on across the footwells and gearbox tunnel- my footwells were like papier mache even after new ones had been welded in!

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There is a similar thread on LRO i think, suggestion there was to galv it, but allow it to cool in the air, not dunked or hosed down.

although i can't imagine that galvanisers will hose stuff down anyway?

i might rust! :ph34r:

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Warping is definately the issue: all the galvanised chassis you can buy are 3 mm wall thickness (as opposed to 2mm for a standard lr chassis).

I believe the bulkhead is 1.6 mm, so there is your answer. However, the swedish based canadian todt I think his name was has succesfully galvanised his bulkhead.

The hot dip galvanizing, as the name says goes to about 400 degc and does do its stuff with welded assys. The replacement chassis consists of 4 plates welded at the corneres, so a lot of heat stress is builded up, which then gets released while dipping. However, I have had my chassis galvanised (shortened 90 chassis) and had no problems. This is a genuine landrover one, 2mm thick and consist of 2 u-sections slid over each other and overlap-welded. The two overlap welds generate a lot les heat than 4 corner welds, so therefore (in my theory) this is no problem. Likewise, the bulkhead is mainly spotwelded, so you might be OK.

I had my bulkhead sandblasted and zincsprayed and that gave a very good result and very easy to paint.

Zinc plating I wouldnt go for: try painting it!

Daan

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I've seen fully galved ones on several ocassions. You should probably weld a box section tube between the chassis attachment points at the base of the door pillars to keep that critical dimension in shape. It might be advisable to do the same at the top across the windscreen attachment points. Rest of it should be ok, sheet metal work is thin so should heat up quickly and not distort.

For galvanising the metal is dipped in an acid bath b4 hand to remove all paint and grud. It would be a good idea to to get it sandbalasted 1st as that will show up an thin areas which can be welded b4 hand. I think there is a dip in a 2nd tank to act as a flux b4 the final hot dip in zinc.

Mark Evans in a 4x4 is born showed the process when he had his hybrid (ex rangie) chassis galved.

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:D Catagorically, the answer is yes you can galvanise a bulkhead. I have done several, for both my own motors, and customers.

The knack.

1) Extra holes need to be drilled to get the zinc inside, and out again. Without this your lovely bulkhead will expand, and blow a hole in any hollow sections.

2) Your choice of galvers, i am very particular about who does my gates, railings, and Land Rover components. Many IMHO run the Zinc tanks too hot. This, and this alone causes much of the distortion.

3) Part of 2 really, few galvers keep the tank fluid clean, hence you get a skumy finish. When your bulkhead any any other item for that matter is lifted out, the floating scum sticks to the finished work piece, and is difficult to remove. Some employ a YTS lad with an angle grinder with flap wheel to remove this muck.... and some of the galv in the process.

4) The most important, i have a jig built to hold the bulkhead true, and square, and therefore delivers 100%.

Also, not to be underestimated is the amount of post galv work to be done. The mesh for the vent flabs gets clogged up with zinc, and a few other problems, non that serious just takes time to tidy them up.

Most of the chassis boys are now producing bulkheads, talk to them, or drop me a PM if you have a requirement. Believe me its the labour that pushes the price up.

Just to put this into prespective, i have galved everthing from body cappings, to springs, trailing arms hockey sticks, brake back plates, spink cups, rad frame etc etc

Hope that helps.

Cheers

Oz

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The mesh for the vent flabs gets clogged up with zinc

I thought those were ally and rivetted on - surely these should be removed prior to galving??? :blink:

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I've fitted a galv bulkhead to a 90 before, it was a new bulkhead which was then dipped at the local galvers

There was some slight bowing in the footwell pannels, (not a problem really) The main things were galv in holes (just needed drilling out) but galv in the holes for the flap hinges and the flap mesh is a bit of a problem

The hinge holes are very difficult to clean out, and the mesh is impossible to clean out, could be worth removing it first

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Nope,

early series stuff was aly, and screwed on. 90/110 Defender onwards are welded in place. Makes a dog to remove them, and even more time consuming to re-fab a replacement. So its quicker and cheaper to leave in place (as its welded at the factory).... At the end of the day you can have what ever is required, it just comes down to fab time. Trying to tell someone this bulkhead costs another £100 'cos i remaid a set of fly screens prob isn't economical.... or i can spend 2ish hours making good the existing...

But.... Anythings possible.

To me its like chassis, it takes time to develop one that doesn't twist in the heat / galv process.

Hope that helps

Oz

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Just checked mine. The current (believed early 200 bulkhead) has the mesh pop rivetted in place. Not sure about removing the TD5 mesh and using this instead though, think I'll just get the mesh galvanised and take my chances.

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My hybrid has a new bulkhead that i bought off ebay.

The rail section that holds the bonnet rubber is ali? no serface rust on it so it aint steel.

I'll get a pic of it think its a 300 tdi but not sure. not worried for £75! she'll fit.

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I've just bought a 1987 Ninety 2.5 Petrol rebuild project and want to bump this thread to see what the current view is. At the moment I've looked in mags and Ashtree seem to be the only people that do it, at £800. I have a local guy who says he will rebuild mine for £1200, galving will be about £200 extra. What I'd like to know is if this is a good price, it includes taking it out, doing all the rebuild etc respraying it and putting it back in.

Thoughts please?

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that seems extremely steep! IIRC it's about £850 to swap a whole chassis so 1200 for a bulkhead is a lot. I have done a couple now it takes an easy weekend with a couple of mates. I paid £70 for my last bulkhead, £40 for blasting, £40 for electroplating and £20 worth of paint

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Nope,

early series stuff was aly, and screwed on. 90/110 Defender onwards are welded in place.

Oz

My 1984 90 bulkhead vents are ally and screwed in.

Edit! Gawd... just spotted the date on this :-)

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Ignoring the necrobump...

I paid £50 to have my bulkhead galved recently, although there was a further £75 to have the paint stripped off using a chemical dip at a place that deals in stripping classic cars for bare metal restorations. You can probably get it blasted for cheaper, but the dip gives a much better job.

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Ignoring the necrobump...

I paid £50 to have my bulkhead galved recently, although there was a further £75 to have the paint stripped off using a chemical dip at a place that deals in stripping classic cars for bare metal restorations. You can probably get it blasted for cheaper, but the dip gives a much better job.

What did you do about corrosion? or did the chemical dip remove that?

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I have an Ashtree bulkhead on mine. The only thing I had to do to it was run a tap through the rivnuts for the fuel filter etc. No warping, and considering that I fitted it to a replacement galv chassis (Richard Chassis) at the same time I was amazed at how easy evrything lined up when it went back together.

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Mine was new, so there wasnt much, but the chemical dipping people, and the galv company both use some sort of acid bath which i believe removes any rust.

When people talk about warping, i dont think they typically warp such that they will no longer bolt on, but the thin flat panel work does tend to warp/buckle a bit, such that flat surfaces become uneven or twisted slightly.

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When people talk about warping, i dont think they typically warp such that they will no longer bolt on, but the thin flat panel work does tend to warp/buckle a bit, such that flat surfaces become uneven or twisted slightly.

Much like the rest of the panelwork then :)

Mo

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Ashtree seem to be a bit of a rip off imo. I got mine from a bloke ont he forusm (not sure if he is on this one mind) and he repairs then galvs them. He has different prices for different quality ones, I think mine was about £500 for one in a pretty good state.

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Ashtree seem to be a bit of a rip off imo. I got mine from a bloke ont he forusm (not sure if he is on this one mind) and he repairs then galvs them. He has different prices for different quality ones, I think mine was about £500 for one in a pretty good state.

Have you a name or contact please ?

I think mine will have to be done soon. So is the galvanised bulkhead painted or left galvanised ?

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I think he goes by the name of ghound on the forums. Based in Ireland, but very happily ships over here.

It is left galvanised.

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