Fascinating. I've never used magnets. I doubt that I ever will. Thanks.

13 minutes ago, Mark Maras said:

 Fascinating. I've never used magnets. I doubt that I ever will. Thanks.

I have several triangle magnets that help you square up pieces to each other and hold them. I use them when I make structural brackets for work or steel posts and such. I have never noticed an issue before. I will pay closer attention now.

 An interesting test would be attaching different magnets, as well as no magnet, to the same piece of sheet metal and weld near and far from them with the welder settings unchanged.  I have used triangle magnets to hold plate steel 90` when tacking. I didn't notice a difference either.

8 hours ago, Patcon said:

The magnetic field was doing that to the weld puddle.

Cool! I never would have guessed that, but it does make sense. That's the same phenomenon that they use to make the old style (CRT) televisions work. They use magnetic fields to steer the electron beam.

Was the field pulling the arc towards the magnet, or pushing it away? I would assume you should be able to reverse the direction by flipping the magnet over. Not that you're going to try that though.

2 hours ago, Captain Obvious said:

Cool! I never would have guessed that, but it does make sense. That's the same phenomenon that they use to make the old style (CRT) televisions work. They use magnetic fields to steer the electron beam.

Was the field pulling the arc towards the magnet, or pushing it away? I would assume you should be able to reverse the direction by flipping the magnet over. Not that you're going to try that though.

I don't know. It just seemed to splatter everywhere

~ 100 years too late.  You discovered the principal of the TV picture tube!

Cool pic! Even though it makes sense, I just never would have guessed it would affect a welding arc. Physics!!  

For the triangle shaped welding magnets, I'm wondering if they don't cause problems because they are either a) much less powerful/concentrated than what you were working with, or b) the steel shells on the outside corral the field and concentrate it between the two sides.

In any event, thanks for posting about this. It's one mysterious issue that I hopefully won't ever have to figure out for myself!

It would be interesting to see if flipping the magnet over changes the pattern.  Maybe it would pull the molten puddle into the weld?

Most of the angle style magnets have a strong magnet between two pieces of metal. The magnetic field represents a horseshoe shape (if you have ever stuck it on a pile of filings...) between the two sides of the magnet (north and south poles). 

The welder creates a path from the wire (positive) to the ground clamp. If the magnetic clamp is IN THE PATH of the welding circuit, the magnetic field of the clamp will repulse the flow of electrons from the weld contact point. Most of the time, moving the magnetic clamp or the ground clamp will alleviate the issue.

6 hours ago, 240260280 said:

~ 100 years too late.  You discovered the principal of the TV picture tube!

Of course I am!

 

3 hours ago, Captain Obvious said:

Cool pic! Even though it makes sense, I just never would have guessed it would affect a welding arc. Physics!!  

For the triangle shaped welding magnets, I'm wondering if they don't cause problems because they are either a) much less powerful/concentrated than what you were working with, or b) the steel shells on the outside corral the field and concentrate it between the two sides.

In any event, thanks for posting about this. It's one mysterious issue that I hopefully won't ever have to figure out for myself!

The triangle magnets are much weaker.

44 minutes ago, wheee! said:

Most of the angle style magnets have a strong magnet between two pieces of metal. The magnetic field represents a horseshoe shape (if you have ever stuck it on a pile of filings...) between the two sides of the magnet (north and south poles). 

The welder creates a path from the wire (positive) to the ground clamp. If the magnetic clamp is IN THE PATH of the welding circuit, the magnetic field of the clamp will repulse the flow of electrons from the weld contact point. Most of the time, moving the magnetic clamp or the ground clamp will alleviate the issue.

That's good to know!

So ten month later, an update

I have been working on other projects, one of them being Cody's new truck

So I started by doing a pulling

slit this to reshape the curve

and had to rework this bracket above the exhaust outlet

Added in some metal to reshape the curve

Stitched it up and voilà!! It's wrong

The curve under the tail light trims is inconsistent, too big in the middle

 

So I cut again

 

finishes and all ground down

 

I had some surface rust appear in the rear frame rail. I tried to use some Eastwood liquid rust remover but it seemed to make it worse. So I brought the panels outside and used the 90# pressure pot to quickly clean them off

150#s of Black diamond and here it is

Brushed on some epoxy primer on the frame and the rear valance. I think I am ready to put it back together. It's still not quite the way I want it but I have gotten to the point where I don't really care. I figure I won't be able to see it from the drivers seat. So I am going to keep pushing forward. I really want to finish color before it gets too cold