Lincoln Electric Square Wave 200 Part 2: AC Welding

Choosing A Tig Welder For The Home Hobbyist Or Garage Builder

Article And Photos By: Clinton Wallace

Originally Published In The March 2018 Issue Of Cycle Source Magazine

This month I’m going to do some aluminum welding to test out the AC function on the Lincoln Square Wave 200. First off, let me state that I do not consider myself to be a proficient aluminum welder. I have done it once before with a different machine, and it was only to make a small repair. So, this will be my first real attempt at doing any AC welding of any size. The first thing to do is to figure out the settings on the machine. Until I get all the settings figured out I will start by making some passes on a 1/8” piece of flat bar, one of the things that I liked about this machine, is that the settings are simple. On the AC function, the first setting is the amps, which, to start, I set at 120amps. The next function is Pulse which I set at 1.5pps. The third function is AC Balance, which I set at 73. And finally, the last setting is Frequency, which I set at 120. These are just some basic settings  that I figured would get me welding and then I could fine tune from there. One thing to keep in mind when your tig welding anything, is that the material must be clean. It is especially important when your welding aluminum: it isn’t very forgiving.

After making a couple of passes, which weren’t very pleasing, I started making some adjustments on the settings. The one thing that I do when I’m adjusting is that I make small changes and then make several passes before making more adjustments. This allows me to compensate for any errors that I might be making and not the machine. After making several passes and going through multiple pieces of flat bar, I finally got the settings about where I felt I was getting the best results. Now, I’m still a long way away from stacking dimes, but it will be a strong weld, and that to me is what’s important. The welds will always get better looking the more you practice.

I don’t usually have a significant need to do much AC welding. About the only time I would need it would be to do repairs on my wife’s horse trailer. Luckily that’s not the case right now. So, I decided to make some bridle racks for her and I will be making some to give to friends for Christmas. I’m using some 1/8” flat bar and some ½” round bar, this will also test the arc control to see if it  wants to wander any. Once I got all the pieces of round bar cut to length and then bent, I was ready to start. Since I was dealing with two different thicknesses of material, I set the amps on the high side so that I knew that I would get proper penetration. Once I initiated the arc, I would concentrate the heat more on the round bar because it was the thicker of the two pieces. The arc felt very steady and didn’t wander any; it didn’t try to jump from side to side. I felt that I had complete control through the whole weld. Like I said before, this is my first project welding aluminum, so the welds may not be show quality, but my primary  concern was making a good solid weld with good penetration. I did try doing some aluminum welding with another machine that I had, and what I can say is that it was way easier to get the machine set and to start making passes with the Lincoln Square Wave 200.

The other machine that I was using had a lot more settings and features which would be good if I were using it for a more industrial application, or for an already experienced welder. But the average person in their garage doesn’t need all the bells and whistles, especially if they are just starting out. What’s nice about this machine is you can still get the same quality and performance weld as you would with the other more expensive machines but at about half the cost. This machine covers just about everyone, whether you are just starting out learning or the experienced guy that just doesn’t want to spend a lot of money on a machine but still wants a quality weld. I will be looking forward to getting some more practice on some aluminum welding with this machine.