Magnetic Welding Clamps Rock

In this video, I want to alert you to a really useful fabrication tool

I call them magnetic clamps. They're not a clamp in the usual sense, but they are meant to hold ferrous metal together before you weld

Before and during welding. This is the typical size. You can get smaller ones, too

And depending on how you use them, which edges you use, they can give you different angles, too

So, it's quite helpful. And I've got one going here. As you can see, they get kind of..

Well, in a welding shop, they attract all kinds of metal filings and everything

But basically, it just sticks on by magnetic attraction, no matter where you put it

And then it can also hold other pieces, too. If I wanted to weld this on nice and square..

Well, there you go. I've got it. It solves a lot of problems

It would be very difficult to clamp this accurately in any other way

Not only does it hold it securely, but it does allow a little adjustment

So, if I was welding this for real, I'd probably put a square on it and adjust as needed

But there you have it. You should probably get three, four, five of these around

You can easily use that many. The bike rack project that you see as part of the course..

The plans and instructions use these because it's just so useful for holding all those pieces together

I use these things all the time. Now, there's just one thing you need to keep in mind

Magnets lose their magnetic abilities if they get too hot. So, this is just a tacking tool

So, I would not want to go and just sort of weld on all four sides and then call it a day..

with the clamp still in place because that clamp's going to get too hot

And it's going to lose its ability to hold things. So, just a... in a couple of places

And then you take this off. And then away you go. Now, there is one thing you need to keep in mind

And it has to do with keeping things aligned while they're cooling

So, for instance, if I had the magnetic clamp there and I welded a little spot weld here in this corner..

and maybe in this corner, there'd be no problem. But if I welded a whole bead on one side here, what tends to happen is..

Like, it's very hot when it goes down, of course. And like everything, or most everything, it shrinks when it cools

So, what's going to happen is that this is going to tip inwards slightly as this cools..

because the weld bead is shrinking. So, one thing you need to keep in mind is that when you're welding, you need to weld in a symmetrical way

So, I would put a tack here and then a tack here. That's going to stop it from moving this way

And then I can complete my weld beads on either side. If I'm going to be putting a bead on these sides, I would also tack here and tack here first..

and then weld, and then weld. And that's going to preserve the precision that I've built into this assembly when I'm using the clamps