Notes on using a gas lens on our TIG welder
SWARM used a TIG welder to weld the aluminum orbs together. I took some notes about it…
We went through our first bottle of argon on the TIG welder alarmingly quickly. A bottle costs about $80 and a trip to Praxair to refill. Here are some tips that will let us use the gas much more efficiently.
– I am now able to set the pressure at about 21 CFM without any problem. We initially had it at 35 CFM. When welding, you should decrease the pressure until you start seeing little black flecks in the weld. Turn the gas back up just high enough so that you don’t see them any more and you’ll be dialed in.
– Set the post flow down to 3 seconds. We had been leaving it as high as 15 seconds but here’s what I think:
I’ve not seen any difference between a post flow of 3 seconds and one of 15. The aluminum is completely solid after 1-2 seconds. It’s not like you are holding the torch over the weld for 15 seconds anyway.
Con: I’ve noticed that the tungsten discolors when the gas stops short. I’ve noticed that this causes the tungsten to be consumed slightly each time. However, over 5 hours of constant welding, I lost about 1/8″ of tungsten. This hasn’t affected the quality of my welds. If we were working on a slower cooling metal like steel, we’d probably want to extend the post flow time.
– The gas lens lets you put the pressure a little bit lower than the regular nozzle. I think I had to keep it at 25 CFM with the regular nozzle.
– If you have to extend the tungsten electrode to get into tight spots (like welding up the base), you might have to turn the gas pressure up a little to keep the black flecks away. The gas lens will make it so you don’t have to turn the pressure up quite as much. For example, with the regular lens, I needed to leave it at 35 CFM when the electrode was extended. With the gas lens, I can turn it to about 27.