Welding Tips and Tricks

PART 1
I was TIG welding today (well using the TIG welder to make a black sooty blobby mess lol) and got an electric shock from the welder. I think the shock came up through the filler rod. I felt it go across my chest and it was quite a nasty surprise.

Has anybody else got a shock from their machine??

I assume that my work was not grounding on the metal work table very well so the electricity took the path through me.

PART 2
Managed some nice welds today on 2mm aluminium but the majority were dirty and rubbish. I have taken previous advice and am using a dedicated SS wire brush then acetone to clean. (AC and 2% ceriated).

What I am seeing is that before I get to add the filler rod, the weld pool is full of black soot and dirt. The weld pool also does not flow nicely like it should but rather congeals. Waiting a while longer just sees the material blow through.

When cutting the aluminium sheet I am using either a circular saw or a 1mm cutting disk in the angle grinder. It appears that majority of issues are when I used the angle grinder disk. I partially fixed the issue by using the SS wire brush and acetone before welding but it has not totally fixed it. Are these disks a know issue? Maybe I should cut slightly oversized then use either a flap wheel or metal file to bring it to size.

The other thing I have noted is that if I start to add the filler rod before the weld pool is ready I get alot of contamination. I am finding it hard to find the balance between leaving the weld pool until it is ready vs too much heat and blow through. Trial and error and time on the tool I suppose!

Please post your settings of your machine, and your gas flows.

i would check all the electrical connections.
craig

On AC, if you are in contact with metal and the ground is not solid, you are in the path of the current. For instance, standing up welding on a piece of aluminum that itself is supported by saw horses with rubber feet. Lay on the aluminum, you'll often get a nice buzz. (Don't ask me why I know this...)

As for the contamination, it sounds as though you are not using enough amps to get your puddle started. With AC, a foot pedal or torch switch to control/taper the heat is really necessary for the "mortal welders of the world". Romp the pedal, get your puddle, then taper off as you get going once filer is added, using enough pedal to maintain the puddle with filler introduced.

You should also review the AC Balance setting on your machine. Your description could be set too low on the CLEANING side of the wave. That, and of course, a long arc (technique issue) all contribute readily to contamination and sooty welds.

Cutting with a disc or using a flap wheel is okay, provided you clean well afterwards and prior to welding. I prefer ScotchBrite pads on my small die grinder followed by acetone. Helps remove the contaminants and crack the oxide layer.

Welcome to the world of high frequency! This is a common trick to play on your fitter if he’s an ass. You ground on the pipe but light up your arc on the fitting. Your coworker who is holding the parts togeather becomes the ground. This practice is best used sparingly do to its effectiveness. You can also easily shock your self by lighting up on the filler rod and not the work piece( your elbow was likely resting on the grounded surface) .

Thanks all. I will definitely make sure I have a good ground!

Todays welding went well. A little dirty but all well stuck together.......

mk1_oz wrote:PART 1
I think the shock came up through the filler rod.

This is possible if you have no, or a poor earth and you touch the filler wire to the material before starting the arc.
I've now repeated what some others have already said.