First attempt, rubbish penetration

[Grant]

Right, so got myself all setup and this is my first attempt

Front

Back

At this point the tiny disposable bottle ran out of gas so I've had to pack up!

First to last is left to right, I worked up from 1min, 1max to 2min (hence the hole) varying wire speed. The best penetration was on 1max with a wire speed of 7.

The welder is a BOC Pocket Turbo 130

 

[dopplershift]

Umm... penetration looks fine to me. (Except maybe on the blobby stop/start beads)

I think you could be moving a bit too fast, and maybe you need a bit more gas flow (brown stains).

I'm sure someone else will be along shortly to help you out!

 

[robtheplod]

sorry to butt in, so brown stains indicate lack of gas?

 

[Grant]

Umm... penetration looks fine to me. (Except maybe on the blobby stop/start beads)

I think you could be moving a bit too fast, and maybe you need a bit more gas flow (brown stains).

I'm sure someone else will be along shortly to help you out!

Cheers, the gas ran out on the last few before I realised!

Think you're right on too fast, I was worried about blowing holes, been talking to a mate, going to slow the wire speed down a bit and travel slower

 

[malcolm]

Or wiggle as you weld - moving the torch from side to side is helpful to control speed and also to make sure you arc against both sheets when you join 2 sheets together. Keeps the weld bead more consistent too. Your beads look a bit narrow and I wonder if you'd miss one sheet if you tried to weld two edge to edge.

 

[dopplershift]

sorry to butt in, so brown stains indicate lack of gas?

I'm fairly new to MIG as well, but yes, as far as I know.... the brown indicates that the steel is oxidising due to lack of shielding gas.

 

[bigb1970]

Is there a pressure gas should be roughly set at??sorry to but in...

 

[Wozzaaah]

Around 10 litres per minute is about right, a bit more if you're welding outdoors.
Sometimes that brown staining can be reduced by using a different torch angle.