Welding question with galv..

[fairwynds]

Hi all

I am sending the vans trailing arms for galvanizing soon.
This weekend I plan to remove the old, rusted rear spring seats, by grinding/cold chisel/devine intervention!
I have bought two shiney new replacement spring seats from the nice chaps at Brickwerks.
I have emailed the galvanizing firm with a query - "should I send the new spring seats and the prepared trailing arms separately, so they can be galvanized and returned to me for welding together".
THEY say, yes, and then advise that it would be better to weld the bits together AFTER galvanizing.....

As I no nothing about welding, I wondered what the experts on here would do? Is it ok to weld galvanized bits together? Would I have to grind off the galv at the points being welded - which does seem to defeat the object....?

Your advice and opinions would be appreciated, as Im feeling a bit unsure about this one - thanks

[Oldiebut goodie]

I would have thought that it would be better to weld first for two reasons.
1.... the welding of it afterwards will burn off the galvanizing.
2.... welding galvanized material gives off toxic fumes so would need someone who knows what they are doing and has a fume extractor to work in.

It does appear odd that they said weld afterwards.

[weldore]

Id do it after...by the looks of it,its just a few puddle welds to hold it on
I weld galv every day as long as you do it outside with a slight breeze youll be fine.prolly best to mark up the holes on the arm and clean just the area your welding and run a drill through the holes in the plate first

put a dust mask on if your worried

[fairwynds]

Thanks gents..

[weldore]

While your at the galvers see if they have a bit of galv paint you could put on your welds too

[sarran1955]

Hello,

Tip on welding galve, mask off area to be welded, grind till white sparks fly. Fire an initial tack in,(maybe lots of white smoke) wire brush clean. Do final weld, paint with galv paint.

Wear mask, avoid fumes, drink a pint of milk afterwards.

Cordialement,

[fairwynds]

Wear mask, avoid fumes, drink a pint of milk afterwards.

Cordialement,

thanks, I think ! Health and safety tip of the week methinks......

[bennwedge]

a few years ago i made a chimney out of galvanised pipe for a log burner that went in a geodesic dome . not knowing about the fumes it would give off. lets just say that when i had a party in the dome with 30 people it wasnt just the waccy baccy we were getting high off

[silverbullet]

Nah. Do all welding first, the galv will find it's way in and protect the joins. If you weld after, you've undone all the work and rust will start immediately the moment it gets wet. Forget so-called "galvanizing paint" it's just paint.
I don't know any fabricators who like/enjoy/tolerate welding on galvanized steel.
Just my two bob's worth.

[weldore]

one other thing..if you do decide to do it after,galv spits like a bitch and is harder to control the weld pool .if you dont have the right ppe then you might end up with a few burns on your arms

praps before might be better for you as any pitting in the steel will soak up loads of galv and lets face it..theres gonna be some pitting,but i would do it after

and sarrans tip on pre heating then cleaning the area is top notch

proberbly too late now anyhows

[boatdog]

did i miss something on this post? been a welder for 30 years welded galv a lot, but why have two parts galved then weld them together? then paint the weld? might as well save your money doing the galving and just paint them. when you hot dip the parts every micron is covered in hot zinc and should be good for 25 years soon as you grind/weld over it it will rust even with the best zinc rich paints (galvafroid) is only good for 10years if your lucky, as for drinking a pint of milk? im sure that 10 mins welding isnt going to strip the calcium from your bones that much, but the fumes do act as a cumutive poison. you sometimes end up with zinc chills after welding galv bit like mild flu for a day (not good). did amuse me though reading this post thanks

[fairwynds]

when you hot dip the parts every micron is covered in hot zinc and should be good for 25 years soon as you grind/weld over it it will rust even with the best zinc rich paints (galvafroid) is only good for 10years if your lucky

Well, I guess that settles it! My reason for asking the initial question was prompted by my doubts that 'dipping' the trailing arms AFTER welding on a new spring plate would cover every last spot of steel.... but sounds like it will, and its apparent that welding first/galv after is the preferred option.
Incidently, a local firm has knocked up a couple of reinforcing patches to go over the weakened areas, before the new spring plates are added....a tidy job I reckon, albeit I'm in for a few more mm of 'rear end rise'....!





...weekend's looking good