I've been welding for like six months here and there on my EG and my senior engineering project, so im no expert. A guy a work told me today that if you reverse the polarity on a GMAW Mig welder you can actually push the wire into the joint and make a tiny weld bead, I haven't tried it, sounds like BS has anyone heard of this.

Thanks

 

what polarity is your gun and work clamp connected to now?

 

I know that you reverse polarity if your using gas less wire. But in not sure how it works on regual gas mig.

 

doesnt make since... thats like saying if you reverse the polarity on a TIG machine it will allow for smaller material...

it just doesnt work...

maybe it will make a small bead, but there is gonna be a lack of penetration..

to weld thin ****, you just turn the voltage and wire speed down..

they use MIGs all the time on auto body repairs.. and thats sheet metal... doesnt get a lot thinner than that...

 

You can reverse the polarity with any welder you are using. Look in the manual your welder came with it should tell you max amperages with the polarity reversed for how ever big your electrode/wire is.

I can't really see the benefits, but the option is there if you feel the need to do it.

 

I've never heard of it doing that, but since it only takes ~5min. to do it, why not try it?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by narfdanarf &raquo;</TD></TR><TR><TD CLASS="quote">I can't really see the benefits, but the option is there if you feel the need to do it.</TD></TR></TABLE>

exactly... so what are the benefits.... there are none...

 

i could see the benefit on thin metal as it would reduce burn through
but in theory it would reduce penetration on thicker metals

 

I know that works for stick welding DCEN or DCEP.

 

I know there are certain benifits when doing this with the TIG. I forget which way is which but one way keeps more heat in the metal and less in the torch and the other way is exact opposite, less heat in the metal and more in the torch. There must be similar principles when using MIG I know I read it in Millers handbook. They have ALOT of good info on their site.