Welding Tips and Tricks

Machine is Lincoln Precision 225 Tig
I am doing production welding with the exact same material one after another.
I am tig welding two pieces of 1/8" round tube together with 1/8" piece of flat bar 1 1/2" x 1 1/2".
My question is sometimes when i run my bead the arc is extremely smooth and quiet with just a constant steady sizzle. When it arcs smooth and consistent like that it welds so much better.
Other times for no reason all of the sudden the arc is very inconsistent with lots of snap crackling and popping and not the normal steady sizzle noise. Its harder to get the weld to look perfect when it arcs like that.
Its defiantly not the ground, I have the ground attached sometimes directly to the metal instead of the jig and it makes no difference. Same amps, same filler, same tungsten, same everything sometimes the arc just acts different for no reason.
I wish it would always arc with a steady bacon sizzle like noise because its great when it does.
Is it possible the machine has an issue?

checking the earth and torch cables for fraying or worn connections is the first thing to do

Nothing wrong with ground or cables. When it arcs smooth it welds great, I just cant figure out why the arc changes for no reason.

When this happens what happens to the cleaning action? If at the time of the snapping taking place you see the weld get gray and all wrinkled or just dirtier or just the opposite massive cleaning action. It could be that the machine is malfunctioning and the ac wave is going crazy. I have seen this before, every now and then the machine would just go dcen for a while. Hard to say what it is without seeing it happen.

My first guess, in a production environment, is that some pieces are cleaner than others. A little cutting fluid residue in the weld zone, for example, can cause an erratic arc.

Steve S

Well, the blocks of alluminum are in a bucket and collecting dust. I will try clean everything real good next time I weld.