welding thin car steel.

[johnmaloney88]

ok was having a mess around in college with a licoln 185 mig welder and even at the lowest setting it's just burning through the 1mm steel that i had cut slices in. i was planning on learning to flare arches where you cut slices in the arch flare it then weld up the slices. any advice on setting the welder up? cheers guys

 

[troppo]

G`day john
With work like this you DONT want to run a bead of weld, your only putting too much heat into the panel and its going to distort like hell. What you want to do is tack weld, put a tack in one spot and then in another spacing them out fairly well. Minimize the heat you put into the panel and you`ll minimize the distortion. As for your blow through, make sure your settings are enough and that your wire speed is right, if its too high it will blow through same if its too low. Practice on some scrap, but welds are the hardest but will give the best finish once you clean up your welds.
Cheers mate
Troppo

 

[Iain Westland]

John, what size wire are you using? And even though its quite low total amps the machine at collage might not go down that far. You need to get down to 20A and 0,6mm if possible.

As Troppo said, tack welds are better where possible.

 

[s410man]

also you may be moving to slowly which will cause heat buildup

 

[johnmaloney88]

i'm all very new to this so it is probably just bad technique on my behalf! i tried tackin but once i got to the lip it blew through. but yes i'm thinkin they use .8 wire and the welder might not go down low enough. if i want a welder for doin this type of work as well as chassis work what size welder would i need? cheers for the replies.

 

[johnny max]

Hows it going lad
Were are you in the country
That machine is ok just cut down on your wire size
Johnny

 

[johnmaloney88]

Hows it going lad
Were are you in the country
That machine is ok just cut down on your wire size
Johnny

from mayo but goin to college in leeds doin vehicle body repair. i'll buy my own welder over the summer and will be able to practice properly, i'll get some 0.6 for the thin stuff and 0.8 for chassis work. the weld would lay down with out burning through on solid 1mm when i turned the wire speed down but i didn't get a chance to try it on the slits/butt joints. that's where the main problem was burning the steel at the end of the slits.

 

[troppo]

from mayo but goin to college in leeds doin vehicle body repair. i'll buy my own welder over the summer and will be able to practice properly, i'll get some 0.6 for the thin stuff and 0.8 for chassis work. the weld would lay down with out burning through on solid 1mm when i turned the wire speed down but i didn't get a chance to try it on the slits/butt joints. that's where the main problem was burning the steel at the end of the slits.

G`day again John
If your really worried about burning through on thin but joints try to get hold of some brass or copper sheet maybe 1/4 inch thick to back up the weld. It will help absorb the heat and give it a solid backing to prevent blowing through.
Cheers mate
Troppo

 

[200T]

Hi!

Butt welding 1mm sheet with 0.8mm wire shouldn't be a huge problem, I do it lots at home and at work. But it's a thin line between cold weld & burning through. Timing is everything... Don't expect to 'get it' after just a few practice runs; it took me quite a while to learn it.

The ends/on the corner is always the most difficult part, as far as burning through is concerned. The least area is available, heat builds up rapidly.

Especially on corners/ends the copper trick helps a lot.

 

[Weldinator]

G`day again John
If your really worried about burning through on thin but joints try to get hold of some brass or copper sheet maybe 1/4 inch thick to back up the weld. It will help absorb the heat and give it a solid backing to prevent blowing through.
Cheers mate
Troppo

And because its copper, the weld wont stick to it.

Anyone know where this stuff can be purchased, weldequip dont seem to sell it ?

 

[keith19]

Try a 'non-ferrous metal' scrap merchant, if you have any locally.
Sometimes you can get lucky and find it in several thicknesses, other times they have none in. They will want you to pay a bit more than scrap value, obviously. But it's well worth it.

 

[gavuk]

I've used copper pipe in the past flattened works well,old lumps/strips of brass or aluminium works well ,the busbars from old electrical panels is another great source of copper strips

 

[Weldinator]

Great thanks.

I have searched and it seems no where sells such a tool and i had thought of using some saved copper pipe i have stored for a while now.

 

[johnmaloney88]

cheer's guys, great tips.

eastwood sell copper tools i've just seen there.

http://www.eastwood.com/welders/eastwood-welders-2/clamps-tools.html

 

[Chickenjohn]

ok was having a mess around in college with a licoln 185 mig welder and even at the lowest setting it's just burning through the 1mm steel that i had cut slices in. i was planning on learning to flare arches where you cut slices in the arch flare it then weld up the slices. any advice on setting the welder up? cheers guys

Use the "Thin Metal technique" as detailled in the MIG tutorials section of this website.

 

[Chickenjohn]

And because its copper, the weld wont stick to it.

Anyone know where this stuff can be purchased, weldequip dont seem to sell it ?

I use some scrap bits of copper pipe flattened out and folded over for where I need a heat sink behind my welding.

 

[200T]

I use left-overs from roofing Any roofer should have plenty of thin copper sheet. You can bent it, fold it - good if you need to put it behind tight corners etc.

 

[RonA]

Copper backing tool

Not sure you need 1/4" thick copper to do the job, made a diy tool out of 22mm copper tube squashed flat at one end & with a wooden handle fitted at the other. Seems to work fine for me.

 

[mike 109444]

Don't forget if it's a length of copper tube you use the heat it soakes up will travel down the tube VERY fast so hold with gloved hand or do as RonA has done.

 

[Weldinator]

I currently cant find a suitable sized piece of wooden handle, I'll go down to the woods and get my self a free one

Better than using a long piece of copper tube for a handle, i will have to get a long one as well though for when im inside the inner wings.