.035 wire vs. .045 wire ??????????

Date 03-27-2014 20:19

Take a look at your welding parameters. You will actually get greater deposition from 035 than you do from 045 at the same VA settings.

By SCOTTN

Date 03-27-2014 20:56

We've always used .035 for handrail and stairs. If most of your work is handrails, stairs, and misc., the .035 would be better suited, in my opinion. The structural you mentioned would be ok to use it on as well.

By Smooth Operator (***)

Date 03-27-2014 21:28

That's EXACTLY the conclusion I came up with when comparing parameters for both!!!!!!! How can that be????? Thought I'm missing something?????? :yell:

By lo-hi

Date 03-27-2014 21:52

Wondering what type of machine and parameters you were running? The 045 seems a little big for handrail, but would work under the right combo. Just curious that's all.

By Smooth Operator (***)

Date 03-28-2014 00:08

Lo-hi....... I think the voltage is running around 17-18 volts and wire s-l-o-w , almost like a mechanized tig........ Using old Lincoln DC-250's w/ LN-7 wire feeders.......... Tried using .025 & .023 for handrail w/less than stellar results..... Used .035 with good results but stocking 2 different size wires was a major P.I.T.A!!!!!!!!! Most employees would grab the wrong wire when they ran out and then the problems began..........(I.E. wire slippage , wrong wire speed, wrong voltage and on & on)...... :yell:

By js55

Date 03-28-2014 12:09

Increased I2R heating (essentially preheating of the wire) and current density. It changes the electrical relationship and thereby the deposit rate. The time to go to bigger wire is not to increase deposition, its when the current density becomes too much for a given wire diameter and the arc begins to destabilize.
These are also the reasons why despite the fact that flux cored wire has flux on the inside it gets even higher deposition rates.

By jwright650 (*****)

Date 03-28-2014 12:16

>when the current density becomes too much for a given wire diameter and the arc begins to destabilize.

Jeff can you describe what this looks like to the welder under the hood?

By js55

Date 03-28-2014 13:25

John,
The wire speed will be a lot faster. To an extent wherein the deposition of the smaller wire (the volume of actual metal deposited) will actually be greater than the larger wire at the same settings.
Welding 1A.
Volts are related to arc length.
Current is related to wire speed/burn off rate, etc.
The increased current density in the smaller wire changes the current/wire speed relationship.
Larger wires do not equal deposition rates until they equal current density.
The advantage to larger wires is that they can carry more current overall without destabilization.

By jwright650 (*****)

Date 03-28-2014 13:40

Hi Jeff,
Yeah, I understand all of that and yes, you can really turn up the WFS...what I was asking for was a description of when the arc destabilizes. I may have seen this or I may not have....I'm just not sure what that looks like when looking through the shield. I guess my question is will it get to a point where you just can't feed the wire fast enough to keep the arc short enough so that it doesn't burn back into the tip?

By js55

Date 03-28-2014 14:00

John,
When I have driven solid wires to what I thought was the max what I have seen is increased spatter that cannot be smoothed out, an uncontrollable arc and puddle, fusion defects, erratic burn off, etc.
Burning back to the tip seems to me more a result of an imbalance between volts and amps as opposed to too much amperage or both. With the self correcting nature of a CV machine once the wire starts burning back, increasing the volts, the current will be reduced, as will the burn off rate, based upon the slope of the machine, and cause the wire to move back towards the puddle, increasing stickout, and thereby reducing voltage and finding balance again unless the balance is too much and the burn back melts on the tip before it can respond.

By Lawrence (*****)

Date 03-28-2014 15:23

While the current density info is true... The OP stated he is running 17-18 volts.. Which indicates short circuiting transfer.

If people are taking substantial time to finish grind .045 mig welds, that can be reduced by using smaller electrode wire... .045 also has a smaller "sweet spot" as far as WFS/Voltage relationships go and spatter and LOF are more common.

Current density as it factors into deposition rates is far more important when GMAW Spray parameters are in play.

I agree with other posters that .045 is probably not best suited for handrails...

But I might argue (off topic) about value of .035 vs .045 as far as deposition rates/value. Lbs per hour deposited in Spray GMAW and the reduced cost of .045 vs .035 make the larger electrode wire more attractive in my opinion... In fact I would argue for .052 solid wire if Spray in flat and horizontal positions on material .125 and thicker is the production scenerio.