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Q: Gas Lenses

haven't had my tig machine 1 week and already i *NEED* the rest of the toys... i mean accessories. (is this normal?)

a few books i have recommend buying a torch that will accept gas lenses (Finch). i take this to imply that some torches won't take gas lenses.

though i've also read in the NG archives that gas lenses replace standard collet bodies.

the machine came with a 140A aircooled torch (which baffles me since the welder is 150A @ 30%) .. anyway, i tried installing the only gas lens my local supplier had (a huge 1/8" one) and, although it screws into the torch body, it sticks out about 2" .. other than the fact that 1/8" gas lens is too big for this torch, should i expect to need a new plastic heatshield? (ie, a longer one)

or will a 'normal' 3/32 gas lens be shorter and allow me to use the same sheild?

any telltale signs on a torch that *won't* accept a gas lens? or will they all?

-tony

Reply to
tony
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Yes, the addiction usually progresses that way. Welcome to the club.

Pretty much any torch made will accept a gas lens.

99% of all TIG torches in the world are based on Linde's designs from the 1950's. #2 series and #3 series torches that match these designs are made by everybody. There are some specialty TIG torches made for special applicatiuons like tube welding and hig amperage stuff, that use special parts, but most run of the mill torches are going to be 2 or 3 series torches.

They are more appropriately called "gas lens collet bodies". They replace the standard collet body with a larger structure that filters the shielding gas through screens that remove it's turbulence, giving you far better gas coverage at lower flow rates.

Those large gas lenses are used by pipe welders, and are fairly common. What you want are the more normal sized ones. Just buy some online, or off eBay.

Check out these PDFs

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Read those PDFs, and you will know much more than your local supplier.

Reply to
Ernie Leimkuhler

Ernie, thanks. judging by the collet body (standard) it looks like i have a series 3 aircooled torch. what is the difference between the actual collets? (standard, wedge & reverse) -- advantages/disadvantages?

-tony

Reply to
tony

Reverse collets are very rare. They don't work as well in newer torches. The manufacturers seem to have narrowed the torch head a bit and the reverse collets seem a bit too long now to allow a good seal at the backcap. Reverse collets pretty much last forever because they are so much further from the heat.

Wedge collets are very good. They last a lot longer than split collets of the same size, but they are extremely picky about tungsten diameter. I have had tungstens jam in them from the paint on the end.

Split collets are cheap and very common. They work, but they wear out quickly.

Reply to
Ernie Leimkuhler

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