Welding Worries.

[Luke J]

Hi Peeps,

I need to stick some bits and bobs hanging of the van that are annoying me with some molten metal.

Now what really worries me is (1) I'm a rusty welder, (2) most of all im worrying about the arc and stuff screwing up the stereo stuff( amp and head unit etc) and any computer stuff for the engine (If any)?

I also need to clean the bodywork up rust wise, maybe some wheel arch replacements. And I want to catch the stuctural stuff before it gets to bad for a mot. the rots realy got going since the salting of the roads last xmas

Has anyone got some tips?

Whilst the suns shining make hay and the rust is dry.

Im running a cheepy gassless mig and 2 weeks of summer

[not-a-jappa]

My welding isn't that flash either, angle grinder and die grinder are vital parts of the kit, basically anything that is going to be on show I get someone else to do.
but
Fundamental rule of welding on a vehicle is to disconnect the battery. Welding can cause all manner to damage to the electronics if you don't. Even on pre electronic era machines you can trash the alternator diodes. I'm not saying it will happen, but it can and it does.

Apart from that keep the earth clamp as close to the work as possible and make sure you know where anything susceptible to heat damage might be, stuff like fuel lines, fuel tank, wiring loom, brake lines and the like.

Any number of the others lurking hereabouts have had plenty of practice at panel repairs and can advise you all about that. Enjoy.

[Leeday]

Hi Luke J.
Welding is great fun
As a rule I always disconnect the battery and remove the plug from the back of the alternator (takes a few seconds, better safe than sorry), gasless migs are ok, but will never be as good as a gas mig. Keep the power settings as low as you can to get a decent weld, most vehicle metals are thin (1.0mm) and blowing holes is so easy and you can spend all day trying to fill the holes in with weld (practise with some old metal of the same thickness to get the settings right, weld 2 bits together, turn it over to see if you have penatrated the metal, if the weld is just sat on the surface you need to up the power, if after turning the metal over you have big lumps of weld protruding through you then need less power). Do not try and do one continuous weld as the excessive heat will twist and warp the metal. Tack weld all new metal panels in place, then weld an inch, leave a gap weld an inch, etc, taking your time is the key... the hotter it gets the more it will disform. be sure to weld to good metal.. any rust present will just make the metal dissapear when you try to weld as it will be even thinner than the original metal and melt away. Be careful of what is behind any panels you are welding...underseal and paint love to catch fire with the heat of the weld. wiring will melt and leave you with a nice loom of copper wire with no outer insulation. Be very wary of the fuel tank... if its petrol, remember petrol doesn`t catch fire the fumes do.... so any fumes around will ignite when you squeeze the trigger... basically preperation and time is the key...Hope this helps,
be safe

[bigbad mothertrucker]

good advice there leeday....i also like to have someone supervise me with a fire extingusher or even a squeezy bottle full of water as fires tend to start when my head is in the land of darkness.plus wire brush all metal to be welded

[doughythevanman]

I am using a Clarke pro90 with gas and that is ideal for panel / plate work as it's not overly powerful but it is good enough to give good penetration and welds on vehicles. I can only agree with the rest of the lads really and make sure you prepare the area well as you can. I would suggest a set of welding clamps or mole grips to keep the panel in place so all you have to worry about is the welding and you are assure of a good fit before you you start. Take your time and you will find it pretty enjoyable!

[Ollie]

Just to add my two pennies worth, the key to not frying stuff is to get the earth properly calmped on clean steel, and disconnecting the battery doesn't do anything much - the battery isn't the bit you're going to fry! Ive never replaced an alternator on any car I've welded - only on newer ones which don't rust!

The only stuff worth worrying about is modern ecu driven stuff, like Airbags and ABS and so on - of which your tranny should have none! Disconnecting all of that is nigh on impossible, so you can buy a clamp on supressor instead, sealey have one in there catalogue so I guess they do something? anyone used one?

As a serious note if you can't disconnect everything, you would be better disconnecting nothing at least that way you get the shared benefit of every items supression capacity, after all a battery is more of a big capacitor than 2 bare wires dangling loose....

[Leeday]

The reason I disconnect the battery when welding is not to save the battery from being damaged, but to disconnect all electrical circuits of the vehicle. With the battery connected all electrical circuits are connected in a loop and when you weld you are passing an electrical current through the metal work of the vehicle far higher than the alternator can ever dream of doing, this can (not will) cause some components to be damaged as they were not designed to cope with such a high surge. For the few seconds it takes to disconnect the battery, I would say disconnect it....... I know my body can cope with some electricity through it but I would rather switch the fusebox off in the house before I change a wall socket

[not-a-jappa]

The reason I disconnect the battery when welding is not to save the battery from being damaged, but to disconnect all electrical circuits of the vehicle. With the battery connected all electrical circuits are connected in a loop and when you weld you are passing an electrical current through the metal work of the vehicle far higher than the alternator can ever dream of doing, this can (not will) cause some components to be damaged as they were not designed to cope with such a high surge. For the few seconds it takes to disconnect the battery, I would say disconnect it....... I know my body can cope with some electricity through it but I would rather switch the fusebox off in the house before I change a wall socket

Agreed,
Some people can hang onto electric fences and not get a belt, my heart goes out of whack for a day Some people get away with not disconnecting before welding, but its standard practice in every workshop I've dealt with. The guys don't always think where the earth clamp is going, and they don't always clean everything up properly before they start, especially if its a small job being done under pressure. It only has to happen once, especially with a "modern".

We can all do million dollar jobs with our eyes shut and our hands tied behind our backs, Its always a $500 job that turns to sh*t, big time.

[darkbluevanman]

I ended up buying a thingey that clips on both batt terminals, lot quicker...

[Luke J]

Thanks guys, this is much better advise than the research one does on the old internet.

Well the back of my desk chair fell orf today, so i got a bit more practice in .

When the weather makes its mind up i'm going in!
I might even post my dog turd look alike welding efforts.

Wish me luck

[campervan06]

Thanks guys, this is much better advise than the research one does on the old internet.

Well the back of my desk chair fell orf today, so i got a bit more practice in .

When the weather makes its mind up i'm going in!
I might even post my dog turd look alike welding efforts.

Wish me luck

try here goes hand in hand with transits
http://www.mig-welding.co.uk/forum/index.php

[Leeday]

Hey Luke J..
Good luck
As long as the weld penetrates and is good and strong, the top "ugly" stuff can be ground flush and it then looks like an expert has done it........ well sort of

[not-a-jappa]

Hee hee, its called seagull welding, it looks like a seagull with the shits flew past, and anyone who claims never to have done any is lying, we all have.
Have a look at the books for the technique, but get to know how to get the best out of your welder by practice, practice, and practice some more.
Enjoy.