On Sat, 01 Oct 2016 14:48:14 -0500, Jon Elson
wrote:

Larry Jaques wrote:


Were you using less or more gas with the standard cup?

The standard cupo produces turbulent mixing with the surrounding air. The
gas lens produces minimum turbulence, so that air is not introduced near the
electrode. If you hold the torch so a stong light makes a shadow on a wall,
you can easily see the flow of argon, and see the difference in how smoothly
a gas lens flows out of the cup.

Do machines with water cooled torches not have that delay?
tilts head
My Lincoln Square Wave TIG has adjustable pre-flow and post-flow timer
settings. The gas valve is in the WELDER, not the cooler, so it is a welder
function. So, it wouldn't care about the torch cooling. I have only used a
water-cooled torch. I can't imagine air-cooled can be used at high current,
the electrode gets WAYY hotter than the work.

Jon
Air cooled (actually GAS cooled) torches are available for use up to
300 amps. I used to have one. My new welder came with a gas cooled
torch good for 200 amps. I exceeded the duty cycle for a 200 amp gas
cooled that I used to own. I had been welding aluminum at the time. On
several occasions I had done this, gotten the torch so hot I could
only hold on to the very end of the torch handle. The last straw was
when, as I was welding, the weld quality started to suffer and I
noticed a strange burning smell. Flipping up the hood I saw that the
torch was smoking. Smoke was pouring out of the cup as well as off of
the outside. That's when I switched to water cooling.
Eric