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Jim Yanik Jim Yanik is offline
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Default First welder- casual use

wrote in
:

On Wed, 2 Jan 2008 07:35:52 -0800, Larry Caldwell
wrote:

In article , not-registered-
) says...

Have you (or anyone else) ever used a DC welder? What's the
difference? I learned to weld with AC, got fairly good at it, and
that's pretty much all I know.


The difference is that you can choose which direction the electrons
flow. If they flow from your electrode to the work, they heat the work
more. If they flow from the work to the stick, they heat the stick
more. For heavy work, a DC welder gives better penetration. For light
work, reverse the polarity and it's less likely to burn through. Other
than that, it's pretty much the same game.


So what you're saying is that the person changes the polarity to
achieve the desired result, correct? I am going to assume that
positive on the welding rod and negative on the steel being welded
would be the setting used for deeper penetration, and if reversed, it
would be for avoiding burn thru. Is this correct, or is it the
opposite of that?



I would think it's the opposite;negative rod for deeper penetration of
weld.(neg to pos electron flow.) The E-beam from the rod strikes the
workpiece and delivers it's energy to the piece.

Thanks for the advice. I now understand the use of a DC welder.
Now I wish I had one to give it a try....






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Jim Yanik
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