first time welding

[Dale1981]

Hi guys wonder if you can help,

ive had my migatronic rally 166 for a couple of years, doing the odd bit of bodywork here and there, now i need to have a go at some chassis work,
ive got some 3mm 4mm and 5mm offcuts from a friend, i spent tonight trying to get some decent penetration but with no joy, heres a couple of pics, sorry weldings crap its my first time welding anything of substance

has anyone got any tips for me, currently is on full power with wire speed around around 7-8

 

[BChild]

Less wire feed and travel slower (I may be miles out with that comment)

 

[Dale1981]

are you saying the slower the wire speed the more heat i should get?

 

[BChild]

are you saying the slower the wire speed the more heat i should get?

More wire speed = more amps but it sounded like you are flat out anyway

So travel slower with the torch to try and get the heat into the work in one place and move slower to get penetration

Like I said still learning myself so bound to be wrong

 

[Bsmith]

If your mig is at max setting then what BChild says is all thats left to try, except getting a bigger mig welder. Not bad welds, just lack heat on the thicker pieces.

 

[BillJ]

For butt-welding that thickness of material you're probably better off with a bit of a gap between them rather than banging them tight together. The clue is in the 2nd photo where you seem to have got full penetration right at the right-hand end where there was a bigger gap.

And/or you can bevel the edges of the two pieces and weave side-to-side as you weld to fill the "vee". That will also have the effect of slowing your travel and putting more heat into the weld.

Not sure how to tackle the lap-welds. Like BChild, I'm a novice too...

[Edit] Just had another thought. If you're used to welding thin bodywork, have you got 0.6mm wire loaded in your machine? If so, you won't be getting full power and should change to 0.8mm for material as thick as this.

 

[JayRS4]

What wire size are you using, if it`s 0.6 then going up to 0.8 will help get a bit more heat in.

From the bead shape and ripples I think your torch angle could be too shallow.

Migatronic 166, 160 amps six settings? Might be a bit short on power for 5mm (which all those pieces look like at a minimum), you`ll need to prep more.

Pictures 1, 2, 4 and 5 youve got a thick mill scale on the metal, grind it back to shiney. Pic 3 youve got rust, smae applies, needs to be ground back.

I know theres no prep, and little penetration, but your beads look very raised, what gas mix are you using?

Doh, just noticed Bill mentioned wire size too.

 

[Tino]

More prep as JayRS4 says. You could also try a good pre heat. 50-100*c will help.