Galvanising question

Tim M · 10 March 2009, 22:45

I've got a trailer I want to modify. The old galvanising is looking pretty tired, plus I want the new bits galvanised. If I modify it and send it to the galvanisers, will they accept it as a mix of old and new? Is there any special prep you need to do to previously galvanised steel?

jwalker · 10 March 2009, 22:55

Quote:

Originally Posted by Tim M

I've got a trailer I want to modify. The old galvanising is looking pretty tired, plus I want the new bits galvanised. If I modify it and send it to the galvanisers, will they accept it as a mix of old and new? Is there any special prep you need to do to previously galvanised steel?

The galvanisers are usually ok with that. They will send it for blasting to remove all the dross and old zinc. Cost you tho. Phone em and ask.

bedajim · 10 March 2009, 22:57

Quote:

Originally Posted by Tim M

I've got a trailer I want to modify. The old galvanising is looking pretty tired, plus I want the new bits galvanised. If I modify it and send it to the galvanisers, will they accept it as a mix of old and new? Is there any special prep you need to do to previously galvanised steel?

Yep and charge extra to sort it out

No rust
no paint

You will probably need to shot blast the whole thing, then any galvanizing left on will be sorted by the pickling treatment pre galvanizing

All box tube sections to be drilled for draining + to allow the air to vent

After galvanizing you will need to clean out(drill) any holes + re tap any threaded holes before refitting of bits

Oh and blow out any shot blasting dust with an air line( before its galvanized)

Also any pigeon crap welds will often blow apart during galvanizing so they need to be done by someone who knows what they are doing

Jim

martini · 10 March 2009, 23:00

Shouldnt need blasting, it gets dipped in chemicals to clean and degrease. Double dipping is a known process used for extra protection so the old zinc wont be a problem.

If its only smallish areas then you can buy these sticks of zinc which you can apply on with a little blow torch. Or even just give it a good coat of galvafroid, should get a year or 2 before the rust comes back.

Tim M · 10 March 2009, 23:05

Quote:

Originally Posted by bedajim

Also any pigeon crap welds will often blow apart during galvanizing so they need to be done by someone who knows what they are doing

Galvafroid it is then

bedajim · 10 March 2009, 23:10

Quote:

Originally Posted by martini

Shouldnt need blasting, it gets dipped in chemicals to clean and degrease. Double dipping is a known process used for extra protection so the old zinc wont be a problem.

If its only smallish areas then you can buy these sticks of zinc which you can apply on with a little blow torch. Or even just give it a good coat of galvafroid, should get a year or 2 before the rust comes back.

We've done some big stuff that needed to be double dipped, one end then the other with an over lap no problems but as soon as we have welded new to old or clean to galv, even with cleaning back first the local guys make us shot blast the crap off + any rust or paint

Mollers · 10 March 2009, 23:10

Quote:

Originally Posted by bedajim

Also any pigeon crap welds will often blow apart......

Jim

By 'pigeon crap' are you refering to 'seagull shit' welding?

bedajim · 10 March 2009, 23:12

Quote:

Originally Posted by Tim M

Galvafroid it is then

the thick hand painted stuff works the best ,but the spray on looks better in the short term if your tying to move it on

martini · 10 March 2009, 23:13

Just had a big pair of fancy entrance gates delivered back to us from Wessex Galvanisers. After spending hours and hours cleaning every bit of spatter off the whole thing is covered in lumps and bumps and runs etc. Great big drips off every single finial, several areas where the galv reacted or something its been sanded down then sprayed up with silver paint!!

If they were my gates I certainly wouldnt accept them but they know theres not much we can do once they've been shipped back across the Channel.

And dont get me started on the shipping companies! One finial has been broken off and dissapeared and the 2 next to it were bent over almost 90 degrees!

bedajim · 10 March 2009, 23:13

Quote:

Originally Posted by Mollers

By 'pigeon crap' are you refering to 'seagull shit' welding?

This far inland it's Pigeon shit

bedajim · 10 March 2009, 23:17

Quote:

Originally Posted by martini

Just had a big pair of fancy entrance gates delivered back to us from Wessex Galvanisers. After spending hours and hours cleaning every bit of spatter off the whole thing is covered in lumps and bumps and runs etc. Great big drips off every single finial, several areas where the galv reacted or something its been sanded down then sprayed up with silver paint!!

Yep that's the new industry standard we use welding gauntlets to handle the stuff till we can dress it with a file

Tim M · 10 March 2009, 23:17

Quote:

Originally Posted by bedajim

the thick hand painted stuff works the best ,but the spray on looks better in the short term if your tying to move it on

Its only for personal use so I'm not bothered how it looks as long as it keeps the rust at bay.

The company that does the work for Hayling trailers said it would be 1.5x normal prices for all-ready galvanised stuff, just wasn't sure about a mixed job.

Thanks for all the replies.

Downhilldai · 11 March 2009, 00:19

Quote:

Originally Posted by Tim M

Its only for personal use ...

I think there are better products than galvafroid out there for that.....

Trailer Bloke · 11 March 2009, 18:36

Quote:

Originally Posted by Tim M

Its only for personal use so I'm not bothered how it looks as long as it keeps the rust at bay.

The company that does the work for Hayling trailers said it would be 1.5x normal prices for all-ready galvanised stuff, just wasn't sure about a mixed job.

Thanks for all the replies.

Tim I have some glavafroid in my garage I thgink if you want some

Tim M · 11 March 2009, 18:53

Hi Simeon. Very kind. Let me know when you want your tent back

TUFTY · 11 March 2009, 21:36

Quote:

Originally Posted by Downhilldai

I think there are better products than galvafroid out there for that.....

What are the better products and where could I get some from?

Cheers

Tufty

Downhilldai · 11 March 2009, 21:57

Quote:

Originally Posted by TUFTY

What are the better products and where could I get some from?

Cheers

Tufty

You'd better ask gArfie.

greenkeg · 12 March 2009, 12:07

just thought have u tried, www.frost.co.uk i used them a lot when i restored my mini cooper,they have all the rust eaters ,paints and prep chemicals and everything you need worth a visit ,tony