Рет қаралды 99,780
From www.kevincaron.com - (Blooper alert!) Artist Kevin Caron takes time out from creating his latest sculpture to answer a viewer's question about using a TIG welder without a foot pedal or high frequency, which is called "lift start." He explains that most TIG welders have different ways to start the arc: the foot pedal, the trigger on the welding torch itself, a high frequency start and a lift start. The high frequency start allows you to just get close to your work with the torch and push on the button or foot pedal. The arc will jump the gap, and you can begin welding. With a lift start, or "scratch start," you have no pedal and no high frequency. No matter how many times you push that trigger, the arc won't jump to the metal. You have to push the button and touch the metal to start the welding arc. As soon as you pull back the torch slightly, the welder sends all of its power to start the arc. Then you can weld. When you're done, you push the button again to turn the welding arc off. The post flow gas kicks in to cool the weld down, and you're done. Caron shows how to change to lift start on his Longevity TigWeld 250 AC/DC by simply flipping a switch from "HF" (High Frequency) to "Lift." Now the foot pedal and high frequency are disabled. Why would you use lift if you have high frequency? The high frequency can interfere with electronics, including TVs, radios, computers and, most important, pacemakers - the high frequency can actually kill someone with a pacemaker! Next, Caron shows how to TIG weld using lift start. He clicks the button and nothing happens, then he holds the button, touches the tungsten to the metal and pulls back the distance he wants to be from the metal to weld. When he is done welding, he touches the button to stop the arc. Whether you use high frequency and the foot pedal or lift start, the quality and appearance of the weld is the same. The welding experience is different, though. Unless you have a torch that has both the on / off and a control wheel or slider that lets you control the amperage from the torch, when using lift start, you have to control amperage at the welder. When using high frequency and a foot pedal, you can control the amperage right under your foot. That's great if you're working at the bench, but not if you are working on a large sculpture, on a car, or anywhere else you are "upsidedown and backwards." Then you can run the high frequency and the trigger, unless electronics are involved. Lift start can be helpful, especially if you have it set up properly to begin with or have someone who can adjust the amperage for you at the machine. For more how-to videos, visit www.kevincaron.com