Gulvanised Bulkhead (white powder)

Hello! Been ages since I've been on here but I've finally started to rebuild my series 3 . New chassis on it's ways from richards in the next few weeks so looking forward to that.

Got a refurbished bulkhead for a decent price and had it gulvanised at the local gulvanisers about 4-5 months ago. It's been sitting in the shed since then and now I've found white power forming and what look like rust in the seam... Really hope it's not. From what I'm reading white rust is common but can I stop it and had anyone had experience of doing this? Want to get the bulkhead etch primed and painted fairly soon but need this sorted first (especially that bit in the seam)

Any help greatly appreciated
Thanks

That looks like normal rust to me

The white powder is a kind of bloom that often builds up on zinc coatings and can be found on everything from dustbins to roofing sheets. No problem - just clean it off and prime and you should be OK. The rusty stuff looks like the zinc hasn't quite taken on the underlying rust. If you've just bought the bulkhead you could complain and ask for a better one! If not, slather it with rust remover before painting. It looks like the rust is in between the sheets of metal so will be difficult to eliminate completely. If it was mine I'd try and soak some penetrating rust treatment like Dinitrol 3125 into the join and then clean off the excess prior to painting.

Edit - I see you had it done 4-5 months ago, so the take it back and complain option isn't a runner!

the white powder is what galvanic protection is about the zinc turns to white powder rather than the steel rusting, bare patches of steel surrounded by zinc will surface rust but not rot like un galvanised steel, that looks like rust prior to galvanising,eventually the zinc will erode away completely but it takes decades

There's a good chance, even if you treat it, it'll continue rusting then blister the paint you put on top of it.
If you've been planning the rebuild for a few years you must be serious about doing a decent job. Cut it out, weld a new bit in, regalv it. Or, get another one, especially if you think there may be other areas that weren't well prepped before it got galvanised.

Al2O3 said:

There's a good chance, even if you treat it, it'll continue rusting then blister the paint you put on top of it.
If you've been planning the rebuild for a few years you must be serious about doing a decent job. Cut it out, weld a new bit in, regalv it. Or, get another one, especially if you think there may be other areas that weren't well prepped before it got galvanised.

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This is the best answer, even though its not what you want to read or do !