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Freehand tig welding technique - Weave Cover pass on a 6" pipe joint - Tig Welding Pipe" TIG welding is not always slower "
You might want to do yourself a big favor and fast forward about 3/4 the way through...you wont miss much. The last fourth of this video is where you can see enough to learn something
Tig welding a weave cover pass on pipe joint using a freehand tig welding technique. There is a perception that tig welding to be a really precise but very slow welding process. But it does not have to be slow. In this video of a welder laying down a cap weave on a 6" pipe joint, you might notice that he is running pretty hot and pretty fast. But when you consider that there is no cleanup afterwards like grinding, or slag chipping, it is not very slow at all. This pipe appears to be schedule 40 and he probably gets it done using about 4 total passes: a root pass, hot pass, fill pass, and cover pass. For the most part, pipe welding codes like ASME call for roughly a 37.5 degree bevel and a 1/8" gap give or take 1/32". In a perfect world, maybe, but in reality, the welder often deals with a wider and inconsitent gap. Good welders can handle a poor fitup every now and then. Really smart welders demand a good fitup. Or they take the time themselves to make sure the fitup is good. A good root pass starts with a good fitup.period. Most pipe welders doing this joint would be walking the cup like in the video below but some welders have found that using the free hand tig welding technique is just as good or better. From from the looks of the weave bead this fella throwed down, You cant argue with his welding technique. It looks like a wedding band even though it was done smokin hot. One thing I cant help but notice, His fingers must be getting really hot. He could really use a piece of heat resistant cloth taped around the 2 fingers he uses to slide along the joint. That would help him slide his hand along the joint without cooking his fingers. A trick I learned on one job was to use some slick heat resistant material as a "hot finger" over my middle finger. You can make a crude hot finger by cutting the thumb out of an old stick welding glove and taping it to the middle finger of your tig welding glove. A "hot finger" really helps to keep your knuckles from cooking when you rest your knuckles on the hot pipe with the freehand tig welding technique like the guy in the video above. Another thing to notice is that he is using a scratch start tig torch. I talk to tig welders all the time who are not even aware that there is such a thing as an air cooled scratch start tig torch. All they have ever used are units with high frequency start and a foot pedal amperage control. Air cooled scratch start tig welding torches are used for their portability and simplicity. All you need is a DC welding machine, argon, flowmeter, and tig torch. Learning to start and stop without leaving defects is a pretty small learning curve to overcome for most tig welders and as you can see in the video, a good looking weld can be made with a simple scratch start rig.
Another tig welding technique for tig welding pipe - "walking the cup""Free hand or walking the cup....whats it gonna be?"
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