Tig welding really is an art form.Most people will not see this however creating the perfect bead of weld in the place you want it does require skill and creativity.The Tig welding process can be used to weld many metals, brass, aluminium, steel, copper, bronze, nickel alloys and gold.
Tig welding or tungsten inert gas welding begins using a tungsten electrode that once struck creates an arc to heat and fuse metals to be welded. The tungsten electrode does not actually touch the work but is held at a distance from the work that is enough to create heat and, with the aid of a filler electrode, fusion occurs. Ads
To eliminate the need for flux a shielding gas is used in a similar manner to mig welding and is delivered via the tig torch itself. The gas, generally pure Argon, protects the weld from outside contamination.
Lay Wire Tig Welding Technique
This Tig Welding Technique is called “lay wire” because the tig welding rod is held in the puddle all the time and is never dipped in and out.The tig torch electrode is walked over the tip of the rod and the end result is a pretty weave that looks somewhat like boot laces. So whats the problem?
Most of the time, this tig welding technique works great. Pipefitters and boilermakers use it all the time to weld pipe, tubes, especially socket welds.But there are situations where it does not work well at all.Like tig welding aluminum or magnesium and Thin Tee joints of any kind in the .032-.070″ thickness range.
If you try to use the lay wire technique on a thin titanium tee joint like is required for aerospace welding tests, you will get lack of fusion in the root every time.For Carbon and Stainless Steel pipe, the lay wire technique has proven its worth in the field with millions of x ray tests over the years.The joint in the video is a 1/4″ wall thickness 1 1/4″ carbon steel tubing.
I remember that sometimes I’d use my torch cup to brace the torch at the right distance. Ya’ gotta pre-set your electrode at the right height, which’ll be dependent on the type of weld (fillet, butt, whatever…) and your torch angle. Take your time doing that, along with setting up your work and your body position properly. The patience during the set up pays off when you’re learning. If you set up the torch so you can use it as a brace, it’s one less thing to manage, and you can concentrate on the torch speed, angle, and your filler rod aim/rhythm/angle. You’ll find that natural rhythm of welding aluminum eventually. It’s a bad ass way of welding.
I ground a 35 degree bevel on each piece so I could have groove to fill in that would work ok with lay wire welding.For the root pass,I gapped it 3/32″ . I used 1/16″ er70s-2 filler rod for the root pass ( i keyholed and dipped the root).
Normally, I would use a bigger rod for the root but I only had 1 3/32″ rod and needed that for the rest of the video to show the lay wire welding.About 75-90 amps on the root pass and 100-115 amps for the weave passes did the trick.a #7 tig cup with 3/32″ 2% lanthanated tungsten and 20 cfh of argon.
The tungsten electrode has to be extended to just the right length to keep the arc length tight. Too long an arc and the tip of the weld wire will get hot too far back and ball up and just blob into the weld. Keeping a tight arc length like you see in the video, lets the rod flow into the puddle nicely and precisely.Using the Lay Wire Technique along with “walking the cup” is a very popular way to weld pipe but the smaller the pipe, the harder is is to walk the cup.
Once you learn how to tig weld it is a most satisfying accomplishment.The tig welding is a very clean process and requires little or no clean-up. This makes it ideal for welds that are highly visible in a decorative situation such as furniture, stainless steel or aluminium components and art work. To me, for most welding that I did, nothing beats TIG, unless you’re sensitive to its naturally lower deposition rate. It’s versatility and weld quality was awesome (provided you weren’t exceeding the technique’s and machine’s capabilities), not to mention it looked fantastic.