Welding thin guage metal

[Erskine]

I'm pretty inexperienced at welding so please be gentle.
I have an Oxford 110 that has had fresh transformer oil and leads and clamps.
The birthday fairy brought me a new light triggered mask and I picked up some new gloves and chipping hammer.

I want to be able to weld thin gauge metal, I know a mig or tig is better but I don't have them. My first attempt at plate just under 2mm using 1.6 rods and 50 amps just blew holes.

My second attempt at 45 amps was much more successful, kind of spot welding it.

And this is the other side.

Does this look ok? Any tips? what can I do to improve it?
All constructive criticism welcome thanks

 

[crazypj]

Not enough penetration, weld is mostly stuck on top.
That looks like 'dexion' shelving uprights?
Should be pretty easy to stick but it gets brittle, gas welding works better on it
Pre-heat the rods, either in oven on baking tray or, get a piece of copper and direct short (they get hot pretty damn quick )
1.6mm should work down to 30amp but you need a bit of extra practice
What electrodes are you using (6 series, 7 series, etc)
Some just light up easier than others
BOC stuff is usually real easy to work with but a bit overpriced, Chinese stuff is variable but useable There's a bunch of others but I forget, about 13~14 yrs since I bought welding supplies in Britain

 

[Erskine]

Thanks PJ,
Yeah it's shelving angle iron that i chopped a bit off to practice on, all that I had that was reasonably thin.
I keep my rods in my sock drawer, so they are dry and room temp, but I didn't heat them up.
I thought that there should have been more penetration. If I turn the amps down and move slow should that give me more penetration with out blowing holes all over the place?
I'm using 'Maypole' branded 6013 rods from the local motor shop, but only have a handful so will need to buy a proper box soon.

 

[Erskine]

I stuck an old pair of shoes together using 2mm rods at 70 amps and they are solid.

I also set fire to my brothers workmate and melted a clamp. Damn.

Oops!

 

[4eyes]

You can use a flat piece of copper to back-up the seam you are welding. It allows the molten weld to "puddle" instead of blow through and drip.

 

[crazypj]

LOL, 'stick' with 45amps and move a little slower. should be possible to get full penetration without too much burn through, just practice.

When I was 'in practice' I could stick weld about 0.030" steel with 1/16" rods, but, I was welding every day at the time (you have to move really, really fast )

I'm pretty crap on thin (>2mm~) material now, just don't do enough welding

 

[Morgan]

A good heat sink under the piece will help by letting the weld cool faster. You can use steel, but you might end up sticking to it which can be damn annoying. A dissimilar metal (i.e. copper, brass or aluminum) backing plate allows you to get away with a lot because you can smack the pieces apart.

Weld downhill. Normally a no-no because it minimizes penetration due to the puddle catching up to the arc, it works like a charm on sheet metal where you don't need much penetration.

Keep the welds short, like a couple of inches, and let the piece cool before continuing. It helps to eliminate 'going good, going good, blop!' that frequently happens. In a similar vein, don't weld to the end of a sheet if you can avoid it because they like to melt off really quickly and leave you with a hole to fill.

Good fit and clean steel will also help a lot because when half the puddle drops into a hole or gets blown off when the arc strikes a piece of crap it is really hard to compensate quickly enough on sheet metal unless you've had a fair bit of experience.

 

[Erskine]

Cheers gents, I'll keep my beadies open for something to use as a heat sink

 

[Morgan]

An aluminum frypan would probably work if you removed any coating on it.* It might even work with the coating, I don't know, but I wouldn't chance it.**


*I'm not responsible for any acts of domestic violence as a result of choosing a spouses favorite pan.

**Who am I kidding, I probably would try it, but I'm dumb and have very poor risk assessment skills.

 

[crazypj]

Yeah, Teflon degrades to cyanide compounds if you get it hot enough (I don't know how or why, I just remember it from when I was training as machinist)

 

[Erskine]

I went skip dipping for some plain tubing and stuff to practice on, I weighed in all my scrap before I moved so need to stock up again.

I've already wrecked my bro's workmate, I daren't risk the wrath by starting on kitchen equipment.

 

[crazypj]

That's a bunch of re-cycleable stuff ;D
BTW, Its 'dumpster diving' over here (just in case you didn't know )

 

[Erskine]

That's a bunch of re-cycleable stuff ;D
BTW, Its 'dumpster diving' over here (just in case you didn't know )

The skip belongs to an outfit that recycles old bikes, it's full of the stuff that's not usable. So you're not that far off the mark!