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: What polarity for dual shield?

redrangie
10-16-2002, 07:17 AM
I was thinking of trying dual shield mig, which polarity would I use? Sorry for the newbie style question, and TIA.

j
redrangie
10-16-2002, 01:08 PM
BTT

I am admitting ignorance here. Someone at least flame me.

j
oldjeep
10-16-2002, 01:14 PM
I have no idea, but why would you want to do that? To blow the flux smoke away from the weld? :D
withamc
10-16-2002, 01:20 PM
Originally posted by oldjeep
I have no idea, but why would you want to do that? To blow the flux smoke away from the weld? :D
I've never tried it, but from what I understand you get the cleanliness of the gas shield plus better penetration.
KYODER
10-16-2002, 01:38 PM
What are you welding? All of the dual sheild welding I have seen has been on 5/8" on up. I don't know of a dual shield wire smaller than 5/64. The machine I used was 400 amps.
YELLER BLAZER
10-16-2002, 01:41 PM
You can use any flux core wire with the positive to the gun and the negative to the ground. Use CO2 for gas and the splatter will be less than standard mig welding and be clean.
KYODER
10-16-2002, 01:45 PM
Originally posted by YELLER BLAZER
You can use any flux core wire with the positive to the gun and the negative to the ground. Use CO2 for gas and the splatter will be less than standard mig welding and be clean.
Okay if you say so, I'll believe ya.
Toddy
10-16-2002, 02:57 PM
We used to run .045 SS flux core and sheld with 75 25 where I used to work. Our wire would not weld with gas on it. Talk about a good looking weld. The flux would just roll up behind your puddle. It would not splatter at all either if you had it set up right. Doesnt really have any tech just my .02

Todd
PIG
10-16-2002, 03:22 PM
Originally posted by redrangie
I was thinking of trying dual shield mig, which polarity would I use? Sorry for the newbie style question, and TIA.

j

Dual shield welding is the SHIT. Run reverse polarity though. Also, you want to run CO2 not the mix.
redrangie
10-16-2002, 05:41 PM
Originally posted by PIG


Dual shield welding is the SHIT. Run reverse polarity though. Also, you want to run CO2 not the mix.

Pig,

Thanks man. I was hoping you would come out of the woodwork on this one. But my question is, REVERSE as apposed to gas or flux? I think you mean reverse to gas, but I need to make sure.

In other words, negative or positive polarity for dual shield?

j
PIG
10-17-2002, 08:47 AM
Originally posted by redrangie


Pig,

Thanks man. I was hoping you would come out of the woodwork on this one. But my question is, REVERSE as apposed to gas or flux? I think you mean reverse to gas, but I need to make sure.

In other words, negative or positive polarity for dual shield?

j

Reverse as opposded to to straight. Straight polarity is DC Electrode Negitive (DCEN). Reverse polarity would be DC Electrode Positive (DCEP). For running dual sheild run DCEN. It will penetrate more because the weld area gets hotter. This is because of the direction the electrons are flowing. In DCEN the electrons flow from the gun to the base metal.
ashmanjeepXJ
10-17-2002, 10:55 AM
Originally posted by PIG

In DCEN the electrons flow from the gun to the base metal.

So DCEN is: ground=(+) gun=(-)

Just to clarify current flows (+) to (-), but electrons flow (-) to (+)

Ill give that a try some time. 100%Co2 and fluxcored,

any disadvantages? why would we not do double sheilding?
mike
10-17-2002, 11:08 AM
Whats funny is Miller shows the flow of current from the ground, through the work and through the gun (electrode) on their site. And thats kinda how I remember my instructor explaining it years ago.
uglyscout
10-17-2002, 11:11 AM
This whole idea of dual shielding sounds like the way to go.

Will it work with my lil' 110V machine or is this only for the big boys?

My machine is currently running .030 and 100% CO2, so it sounds like I am halfway there. So do I really just add the .035 flux wire and keep the gas flowing?

Always looking to squeze a little more life out of my welder.
PIG
10-17-2002, 01:00 PM
Originally posted by mike
Whats funny is Miller shows the flow of current from the ground, through the work and through the gun (electrode) on their site. And thats kinda how I remember my instructor explaining it years ago.

Yea dude, thats the way to go for non FC welding.
mike
10-17-2002, 01:05 PM
and SMAW welding too :D
ashmanjeepXJ
10-17-2002, 01:31 PM
Originally posted by PIG


Yea dude, thats the way to go for non FC welding.

For a Re-cap:

Flux core (gassless): Ground(+) and Gun (-)
A18 Solid Mild Steel Wire (co2(75%) and Argon(25%) mix): Ground(-) Gun(+)
Double shielded, Flux core (co2(100%)): Ground (+) and Gun (-)


correct.
:D
kincade b
10-17-2002, 05:00 PM
Originally posted by ashmanjeepXJ


For a Re-cap:

Flux core (gassless): Ground(+) and Gun (-)
A18 Solid Mild Steel Wire (co2(75%) and Argon(25%) mix): Ground(-) Gun(+)
Double shielded, Flux core (co2(100%)): Ground (+) and Gun (-)


correct.
:D

Out of curiosity - why can't the 75/25 mix be used with dual shield welding? I did my wristed arm w/ dualshield and 75/25, and it seemed to be very clean and work well.

'Anyone?