Video: How to Weld Bandsaw Blades

Welcome to MSC Machinery. This is Larry the Machinery Guy. Today, what we're going to cover is blade welding: why there is a blade welder on the machine, the process that we're going to follow to weld a blade, and also why you would want to have it there.

So, imagine if you had a 12 inch block of material and you want to cut a six inch circle out of that 12 inch block. There's a number of ways to do it, but the most effective way to do it is on the bandsaw. So, what we would do first is identify the center of that hole, drill a hole through the center of that, feed the blade through there, weld the blade, cut it out, break the blade, and then we have a nice six-inch hole in there. A very big time-saving device, and that's why that blade welder is on the machine.

So, if you give me a second or two, we're just going to go over here and we're going to show you the process of how to weld that blade.

First thing we're going to do is—I took a small section of blade I don't want to use a whole piece just as for this demonstration. A key thing to remember also is these are designed for carbon steel blades and not bi-metal blades.

So here we go, we're just going to cut the blade off, theoretical point hopefully between it two pieces. This is a critical portion right here, and people will often forget, to degrease the blade. You ever try to weld something and you have a lot of grease on there? You get a bubbly weld. The same thing applies for welding a blade. So I have a little degreaser over here, I'm going to spritz that and wipe the grease off so I get a nice clean weld.

Next thing I'm going to do is look at the blade, make sure I have the tooth configuration correct where I want it. I'm going to do a mirror image when I grind it so if I am a little off square when I grind the blade for a nice clean edge it's going to match up when I flip it around. And I'm just squaring that up make sure I have a nice clean edge on both sides.

I'm going to put the blade in the blade welder, lock it in place, set my pressure, and what that does is this is called a butt weld, welding two like materials together without any filler. I'm melting that material very rapidly and welding it together. You're going to see little sparks here, hopefully I won't spontaneously combust, and we'll be okay.

So then we'll examine that blade for weld, we have well gone both sides which is great, but we're not done yet. The blade is very very strong at the weld, now if I go to flex that because I have to go around that wheel through the bandsaw, it's going to break. So, we have a process called annealing, where we're going to sacrifice some of that strength for flexibility.

It's called an annealing process. What you do is you put it out here, the second level, and you'll see that blade get a little cherry-red, and I'll gradually decrease the heat, taking some of that strength away and making it a little softer. And before you go any further, what you want to do is you want to flex that blade, make sure that's not going to break when you put it on there. So, I'm pretty satisfied with that.

And the final process is you're going to grind that away. You're going to grind that weld away because that weld has to fit through the guides—the guides are right here—and if you've ever done any blade welding and you hear the thunk-thunk-thunk, that's that weld is not correctly ground. We're going to grind that away, then the final thing is you want to make sure this edge is also square.

So there you have a welded blade ready to go to be put on a bandsaw, flexible enough to go around the arc of that. I'm pretty happy with that.

Thank you for watching the MSC How to Weld a Bandsaw, we're Built To Make You Better. Have a great day.