by Bob Moffatt

Welcome to Weld.com, I'm Bob Moffatt. We're going to do a quick video today, this been done before, but we want to show you some extreme footage here, we're going to put the camera guy to the test.

We're going to do four different grinds of tungsten. We want to look at the arc envelope, the arc start, we want to get some real close footage of this. So we've got a 15 degree grind angle, really sharp point. We've got a 30 degree grind angle, which is what I use a lot of. There is a 30 degree angle with a blunt on, which I use a lot of on aluminum. And then there's a 60 degree angle, which just like barely has any point to it at all, and believe it or not, you may think that this 15 degree grind angle super sharp is the one with the best penetration, versus the one that's kind of stubby here, the 60 degree.

Be amazed, I mean, it might be just the opposite of what you think, so we want to show you this in some critical footage here. I'm going to do this on clean 3/8 plate here. We're running 3/32" e3 tungsten, 100 amps, we're going to be grinding today on a handheld unit offered by Praxair, very nice little unit. This should be quick, simple, but we really want to show you the differences of these grind angles here, be right back.

Okay, I'm not going to be holding anything, I've got a fixture up here, I've got a standoff, so I'm going to set these, we're using 3/32" tungsten, 100 amps, pure argon, 20 cubic feet per hour, I've got this gauged off of this so all of them will be the same. About a five second arc shot or so, just so we can look at the envelope and see what this grind does. This next one's going to be 30 degree without a blunt. This is what I use predominantly, kind of depends on the application, joint configuration, but I'll use this grind a lot, kind of my standard grind.

This next one's going to be 30 degree grind with a blunt on the end. Our last grind that we want to display here is a 60 degree. I don't use this very often, but I will use it on certain joint configurations, especially in piping. Okay, the first one we fired up over here was the 15 degree, the one that's, ah, god dang, that's sharp. The 15 degree one, super sharp end, and you saw what kind of envelope, what kind of arc that it created, and where would we use that, what's typical application for that?

Personally I would use it in something like an outside corner joint where I want more of a wider envelope, not so sharp of an arc. I'd use it in outside corner joints, lap welds, and stuff like that. Lower amperages is where I tend to use them.

The next one we want to talk about, the next one we fired, was the 30 degree bevel, and that's the one that I use a lot of all the time in just about, I want to say, about 80%, 90%, of my welding, 'cause I'm just used to sharpening them that way and it works well in a lot of different applications. Root passes, some fillet welds and stuff like that, I've used it. I don't really go back and resharpen, sometimes I will, but I'll take a 30 and change it to some of these others.

So you know, again, I use this a lot, in a lot of the applications that I do for general purpose work. And then we get to these other two grinds that we fired. There's a 30 degree with a blunt. I use this a lot on high amperage stuff, because I don't want the tungsten to spit, if I'm up on the high end of the current carrying capacity of 3/32" or even an 1/8 inch for that matter, if I'm up on the high end, I don't want this tungsten end to deteriorate and spit, 'cause it'll spit and it'll go right in the weld, we don't want that. So I use these blunts, and I also use this blunt on alternating current, as well.

I realized that everything that we did here was DC, high frequency start to show you some good camera footage and everything, but I use this one here on AC aluminum on an inverter, I'll blunt that end.

And then the last one that we used, or the last one we fired and demonstrated, was this 60 degree, and that little rascal there kind of looks funny