Galvanised plate

[bigrab]

Hi all.
The only 2mm plate I could find for a repair needed on my car is galvanised. Can I just grind off about an inch broad strip where I will be welding, or do I have to be more drastic? any advice would be good. I was also given a large 2mm plate of the same stuff for practice on, a bit over the top but it was all he had handy.
The 2mm plate for the car is shaped for the job and he had to weld a 6" bit on the end, he has that bit a bit shiny where he has ground off the galvy around where he was welding, so I thought that was all I'ld need to do too.

Bigrab.

 

[dai]

just clean off where the weld is going
dont breathe the fumes from galvinising

 

[outofthefire]

A lot depends on how its been galvanised some seems to come off quite well but some seems to penetrate more into the steel. Plus with thin sheet if your not careful you'll end up grinding some of the good steel as well making your sheet thinner. I'd give it a go though if its all you've got.

 

[bigrab]

Hi,

Would a good flap disc from Weldequip do a better cleaning job than my angle grinder? Is there any kind of mask I could use?

Bigrab.

 

[medlar]

a flap disc on your grinder would do a really clean job for you mate

 

[piman]

Hello Bigrab,

if that's the only steel you have, then fine, but 2mm is too thick for car repairs, unless you are repairing the chassis of a car with a separate chassis?

Body panels generally 20 gauge, about 1mm and underframe, 18 to 16 gauge, 1.2mm and 1.6mm.

Alec

 

[bigrab]

Hello Bigrab,

if that's the only steel you have, then fine, but 2mm is too thick for car repairs, unless you are repairing the chassis of a car with a separate chassis?

Body panels generally 20 gauge, about 1mm and underframe, 18 to 16 gauge, 1.2mm and 1.6mm.

Alec

Hi Alec.
It's the rearmost crossmember that the bumper bolts onto, and it is completely rotted along most of its full length of 64" .
My car had a rear end shunt a while back, and I think not enough was done at the repair to safegaurd the crossmember.
I'm going to grind out all of the bottom of it and weld in a new 'L' section and then coat the inside and outside with Bilt-Hamber S50. The fact it's galvanised helps too I hope.

Bigrab

 

[piman]

Hello Bigrab,

Yes, it will certainly help, you just need to treat the welded section as well as possible.

Alec

 

[chris-law]

Go to your local motor factors , they should have some thin sheet , I once spent 2 weeks very I'll and coughing up this brown stinking stuff akin to rotting meat after welding galvo pipe , luckily a chest x ray showed my lungs were ok , I didn't know any better as I was young and only doing what I was asked to do at work .
Even grinding galvo can give you flu like symptoms.

 

[Ratcatcher]

Seriously be careful of welding anything which has been galvanised especially if it's been hot dipped.
When i welded the stuff on a regular basis i tried to make sure all galv had been removed and at the time i never had an air feed mask but made sure there was ventilation-open both doors and let the breeze do it's work.
If you have been welding it make certain you drink milk afterwards "i'm dairy intolerant" as the proteins in the milk will adhere to the zinc and it will pass through your system!.
In a past profession i was involved with chemicals a lot worse than zinc so please don't take chances as a cheap £5 job could crucify you for life!.
As for bumpers:why not do it the steel workers way-weld a piece of railway line on,won't do much for your petrol consumption but god help the next motor that runs into you.......

Rat.