If you have any breeze you might need more gas, too. Go up to 15 or 20 cfh and if the problem goes away, then for those conditions you were not running enough gas. The only way to get the ideal flow is to lower the flow until the weld suffers, then go a little up from there. There are a lot of factors that change how much you need, and experience will teach you to make pretty good estimations after a while. 20-25 cfh is about the max you want to run through a #7, but you can often get away with half that or less. Smaller cups less gas, larger cups more. Short stickout less gas required, long takes more. Some joints trap argon better so for things like flat inside corners you can really crank it down, but a vertical outside corner will need a lot more. The slightest air movement will increase your gas use, and once it gets to a breeze you can feel, you may not be able to TIG at all without some kind of wind break. If you don't have enough post flow, your tungsten will not last. A rule of thumb is 1 second of post flow for every 10 amps. Again this is just a starting point, but any time the tungsten is red, there absolutely has to be argon flowing, and for a little while after. Air cooled torches need longer than water cooled, and so on. If you dip your tungsten, stop and grind it if you want your welds to be quality. When you just start out the easiest thing is to sharpen a few so you can just swap them out and keep welding. After a while you will find you need to swap less and less.
Long arc, short arc, heliarc and in-the-dark!
Reply With Quote
ill try and watch for that now.
