What exactly is 'DIG' setting for stick welding

I do not understand what DIG means... or why it is needed... thanks...
i

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Ignoramus30285 wrote:

Is it one of the switch selections?
Two possibilities are that it is a setting to use when deep penetration is wanted, such as butting two thick plates together, or that it is meant to be used with a gouging torch for grooving out or removing metal.
Just a wild assed guess though.
Cheers Trevor Jones
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From the Miller welder website.
"Offering exceptional arc characteristics for different electrodes and joint designs, the Trailblazer 302 Diesel features four preset DIG settings. Providing combined DIG and Process switch, along with preset DIG settings, offers simple set up without the complication of multiple switches. The four preset DIG settings include: soft arc and smooth 7018 performance, medium-soft driving arc, medium-stiff driving arc and driving arc such as pipe welding."
About the Miller Maxtar 200.
"DIG control allows the arc characteristics to be changed for specific applications and electrodes. Lower the DIG setting for smooth running electrodes like 7018 and increase the DIG setting for stiffer, more penetrating electrodes like 6010."
Miller Inverter power sources
"Dig control for Stick welding. Dig control prevents the electrode from sticking when the arc gets too short. This is helpful for an open-root pass or tight fit-up work and aids in arc initiation."
I am not sure electrically what is changed when you change the DIG setting, but you can see above examples of how the DIG control is supposed to affect the welding arc, apparently by affecting the penetration and tendency to stick. I have heard of this before. As far as I know it affects stick welding only, but I could be mistaken.
Richard
Ignoramus30285 wrote:

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On Thu, 06 Apr 2006 18:06:21 GMT, Ignoramus30285

Arc welding is nominally done with a constant current supply. DIG alters this by increasing current at lower arc voltages resulting from shorter arcs. This keeps rods from sticking, among other things.
The power to the arc is arc current * arc voltage, so as the arc get shorter and voltage drops, power (hence heat) goes down unless current is increased.
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wrote:

Thanks Don, that was a great explanation.
i
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On Thu, 06 Apr 2006 18:06:21 GMT, Ignoramus30285

From: http://www.welding.com/welding_terms.shtml
Arc Force - Also called Dig and Arc Control. Gives a power source variable additional amperage during low voltage (short arc length) conditions while welding. Helps avoid "sticking" stick electrodes when a short arc length is used.
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I always thought the 'arc force' control squared off the edges of the sine wave to give a better 'punch through' voltage. Suppose I'll have to put a 'scope on the output of the stick welder and have a look!
As for what it does for you, increasing the 'arc force' sure helps on rusty or dirty material. Increases the spatter tho.
Ignoramus30285 wrote:

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Roy, I received some helpful answers here and tried to dig some information myself. Here's a little summary.
The story, I think, is as follows: (as Don said) on CC welders, when the electrode is very close to or shorts to work piece, the voltage in the arc drops dramatically and the current at that voltage does not produce much power (power = voltage * current).
Because of low power, there is not enough heat and electrodes stick to workpieces. Very annoying, as it messes with fitup, finish and is generally unpleasant.
To correct it, good welding machines have a "DIG" or "ARC FORCE" adjustment, that increases current when the welder detects a short arc or short circuit condition by seeing low circuit voltage. That instant current increase increases power in the arc, and that instantly "digs" a little hole in work by melting it (and melts more electrode) so that a longer arc is maintained.
That prevents electrode sticking and can help increase penetration.
i
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We have a big AC/DC stick welder sitting in the corner, fairly new, rarely gets used anymore. I doubt it has much of any electronics inside, I need to have a look at how it does the adjustment. Shop manager will have a hissy about taking the case apart but you have my curiosity working.
Ignoramus25712 wrote:

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