Welding Tips and Tricks

Just after some opinions from the wise sages on this board.

Until recently I've only had a gas lens setup for 1.6mm electrodes. My own meagre experience is that the gas lens setup gives me better stability and smoothness, so my conventional collets and cups have been lying idle while I attack pretty much everything with my 1.6mm stubby gas lens rig. My welding is mostly low amps - often 40 amps to occasionally as high as 70.

I recently picked up a 2.4mm gas lens kit. Starting out with a sharply pointed electrode (I'm using 2% lanth for everything) I find that the 2.4mm rig gives me a more stable, focused arc on everything - steel as well as aluminium.

Can anyone tell me why? It's not like at the amps I use the 1.6 stuff is at its limits or anything. Same cleaning regime, same settings, but a sharp 2.4 seems to give me a better arc than the 1.6.

Any opinions on why this might be?


Kym

Are your 1,6mm and 2,4mm tungstens from the same manufacturer? If so, I'd suspect a gas-flow issue. The bigger lens and collet will allow more gas to flow, and more evenly, but a properly configured 1,6 should work just fine. You can also get them in 0,8mm, and even 0,4mm for very fine work.

An unusually common mistake I see is inserting the collet upside-down. This has a greater effect (flow restriction) the smaller the collet is. So to state what may already be obvious to you (just to be sure), the fat head of the collet is up, toward your back-cap, and the skinny end with the two slots goes toward the gas lens.

Steve S

Collet definitely in the right way, Steve!

Yes, electrodes from same manufacturer. Decent quality stuff.

I forgot to mention one variable. The lens I am using with the 1.6mm electrode is a large diameter stubby. The lens I have for the 2.4's is a 'standard' diameter non-stubby.

It's not a chalk and cheese thing, but 2.4's definitely behaving a little better with this set up.


Kym

No electrical theory I can think of that would explain it. Usually people say higher amp density, (smaller tungsten) gives a more stable arc direction. I find with AC, which is a different kind of animal, a 1/16 or 1.6 gives me less arc wander than 3/32 or 2.4 mm. I think the arc is less predictable the longer the taper. Using bigger tungsten usually means a longer taper if flowing the same amperage.