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Up Topic Welding Industry / Technical Discussions / Spray arc .023 wire and why is it "wrong" ?
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- - By PlasmaHead2 (***) Date 10-18-2014 02:21
So the other day I was welding on some nice thin 16 gauge steel with some .023 wire and one of the managers appeared at my bench with some bits of scrap he needed tacked together to work on some panic rush job that just walked in the door. 2 random chunks of about .5" thick round bar and some .25" bits of plate he needed attached to the bar stock so that they would stay in place so he could do whatever he had to do....
Given the panic and the totally non critical nature... I shrugged and cranked up the volts and wire speed and had at it. :eek::eek::eek:
At around 19-20 volts and 400ish IPM it produced a nice hot short circuit transfer and got my brain running...
Why doesn't anyone use .023 wire in spray arc for working on say 1/8th to 1/4 thick material to help get around lack of fusion defects... which leads me to the question of what would be wrong with the concept?:wink::lol:
I'm sure that there is some reason why and I have a feeling its due to some sort of metallurgical reason... but I have no idea what. Any ideas?
Parent - - By Plasma56 (**) Date 10-18-2014 15:09

-Why doesn't anyone use .023 wire in spray arc for working on say 1/8th to 1/4 thick material to help get around lack of fusion defects

Because they can't achieve an axial spray transistion to the wire because it's to small a surface and it over heats.

While this sounds like an easy out in explanation, think pasta. The noodle is so thin it cooks evenly quickly. o/O
I hang two ropes fuses from a ceiling. One thick, one thin. I light the ends touching the floor on fire.
I put my hands around your throat. How much pressure do I squeeze with? How long do I squeeze? How often do I squeeze? How thick is your neck?

Technology hasn't thought it a problem to be over come but I think it could be. But do we need to?
Parent - - By electrode (***) Date 10-18-2014 15:31
ok. I've finished thinking pasta.
What about cost?
Just one more tangible one among a certainly higher - and much more interesting - number of arguments.
Parent - - By PlasmaHead2 (***) Date 10-18-2014 17:12
$23 for 11lbs .023   .47 cents per pound
$102 for 33lbs .035   .32 cents per pound
Not having to switch out spools of wire to change jobs ; Priceless :roll::lol::twisted::twisted::twisted:
Rough numbers from the first prices that popped up on google, I'm sure better prices can be had. 
I could see a robot cell that can handle all sorts of jobs with one big drum of wire and a change in settings. I'm sure some bean counter is twitching at the prospect...:lol:
Parent - By electrode (***) Date 10-18-2014 20:06
"Not having to switch out spools of wire to change jobs ; Priceless".

Parent - - By PlasmaHead2 (***) Date 10-18-2014 17:04
So its a current density issue? The wire is just too small to provide the current needed to hit spray range?
So with all the dials maxed out a .023 wire will stay in the globular range or would it make it to "buried arc" range?
Do we need a system to run .023 in spray arc.... more than likely not. I would love it because then I could have one machine set up to handle anything from paper thin sheet to "light" structure work...
Parent - - By Plasma56 (**) Date 10-19-2014 05:42

Before you think to much about this, take what I tell with a grain of salt. More then a grain of salt if your cooking pasta.
You know. When it comes to pasta, I don't do kd often. Just not a mac and cheese guy. I'm a kd mac guy. I toss the cheese, lather in butter salt and pepper. I quit saving the cheese along time ago. I don't do kd often, but when I do, I watch it like a hawk. I hate over cooked kd.
When I cook spaghetti, I like a little firmness with the noodle. If you think about it, spaghetti, it cooks from the outside inward. Solid wire melts almost the same and up the length it softens?
Funny thing about cooking spaghetti, most use too small a pot? Just saying...? 
In short circuit GMAW, the wire(+) comes out (wfs) hits the plate (-) and shorts out. Current surges up the wire, the end of wire resistance heats up (slope), magnetic field builds from (-)'s of the plate surface climbing up the wire, the (+)'s jumping off the wire, (inductance) the surface and softening length are pinched off. Like milking a cow. plunk,plunk,plunk.
Most never milked a cow. I'm sure a cat works the same way? Constricting rings plunk,plunk,plunk.

This is really a complicated subject but I'm obligated to keep it to my level so work with me here.
Cooking pasta. Pot, water, heat, salt and pasta. How hard it that right?
How big is the pot, how much water is it holding, whats the heat source, did you add salt to the water, and what type thickness and volume of noodle?
GMAW, Axial spray transfer requires about the same.  A power supply,a wire and feeder,gas supply with argon (92%+) more voltage with an increase to wfs.
But you want to spray transfer vermicelli. It cooks quick. Milk that cow.

Make a fist and grip your thumb, grip your baby finger. The higher argon causes the grip with voltage effecting this tightening effect and it's location to the wires length. However, with .023 wire, the wire is to small to be gripped tight enough, rapidly enough to strip droplets small enough to achieve an axial spray. Simply put thats it. Sure, it's more complicated than that but whats a better story. In conclusion. So what the problem really? Teat to small or a hand to big?

"They" can do it actually. "They" can do it.  Google fronius see whats different. I think the regulars have it as well on the upper end power supplies?
.023 solid wire into a spray, the science is there to make it happen. Problem is not enough need it or see a value.

Not sure if it makes sense to you? But I think the hand is to big, the grip not tight enough and to darn slow on the squeeze.
That current density thing sounded good didn't it?
Parent - - By ssbn727 (*****) Date 10-19-2014 17:55
Hi Plasma 2 A.K.A Clif!:grin::wink::cool:
You can GMAW spray transfer with .023 CS filler metal easily with any CV power source... However, it's not a cost effective, nor is it an efficient way of using such a small diameter wire when one can deposit more weld metal @ a lower cost per pound, and in less time and you know about the old saying that "time is money." So stop wasting time using such a small diameter, and inefficient diameter filler metal for GMAW spray because it's costing the company more mullah per lb. than using .035 diameter wire instead...

It's funny that you mentioned pasta Plasma 56... My biggest pet peeve regarding pasta is the fact that too many people not only overcook it... They leave too much water within the pasta after they supposedly drain it!!! I mean Al Dente is good but soggy Al Dente is just WRONG!!! why? because now the excess water gets mixed with the sauce, and turns it into a thick tomato soup with whatever else that was added to the sauce and it ruins the flavor making it a totally lousy culinary experience... "So C'mon people smile on your brother just remember to completely drain the water out of the pasta!":eek::eek::eek:
End of pet peeve.:lol::yell::twisted::yell::lol::yell::grin::smile::roll::surprised::wink::cool:

Parent - - By electrode (***) Date 10-20-2014 10:36

"You can GMAW spray transfer with .023 CS filler metal easily with any CV power source... However, it's not a cost effective, nor is it an efficient way of using such a small diameter wire when one can deposit more weld metal @ a lower cost per pound, and in less time and you know about the old saying that "time is money." So stop wasting time using such a small diameter, and inefficient diameter filler metal for GMAW spray because it's costing the company more mullah per lb. than using .035 diameter wire instead..."

Thank you for picking up the "cost" issues more comprehensively, the background actually of my response to Plasma56.

One thing's for sure.
If there is anything certain that I have learned in here.
In most cases, it is better for me to wait until one of you 'forum founding fathers' had responded.
That prevents me from building "walls of text", maybe aggravating or, even worse, boring someone to death.

Further reading your "So stop wasting time using such a small diameter..."; I dare to assume that you have also correctly interpreted my "Impressive" as what it was actually meant.

Btw. Who is Al Dente? :)
Parent - - By ssbn727 (*****) Date 10-20-2014 21:08

He's my cousin.:grin:

Parent - By electrode (***) Date 10-20-2014 21:21
I did almost suspect that. LOL!
Parent - - By 46.00 (****) Date 10-21-2014 03:41
He's my nephew!
Parent - - By electrode (***) Date 10-21-2014 07:59 Edited 10-21-2014 11:39
So, wait a second ...
Does that mean finally that you're related to Henry? :)
No offence, no offence, gentlemen.

Just trying to joke.
As I mentioned once; actually I'm well-known as belonging the rather humourless species.
Parent - By ssbn727 (*****) Date 10-21-2014 15:22
If that was an attempt to make a joke like  Spock would say then I would suspect that you have succeeded Electrode...:eek::surprised::grin::lol::yell::yell::lol::yell::lol::wink:
You did good :eek::grin::lol::yell::grin::smile:Electrode ya did good!
But I'm afraid ( and happily so) that there's not a chance in hell that me and the little runt called 46.00 would be related... Unless his family line originates in Spain like mine does but I highly doubt that this could be possible... .023 wire good for auto body restoration work, and is what it was developed for.

Parent - - By welderbrent (*****) Date 10-21-2014 17:10
Would you guys please leave my twin brother out of this conversation.  He is really sensitive about all the attention and doesn't like is personal info broadcast out over the internet.

Parent - By electrode (***) Date 10-21-2014 17:52
Parent - - By PlasmaHead2 (***) Date 10-21-2014 21:26
Hey Henry, It is I :grin:
So while I am  beaten on the bean counter end... I still have thoughts and questions about the theory end. Like what if the goal wasn't high Lbs/hour but more penetration and less over welding?
Like what if the call out was for an 1/8" fillet weld, that would be quite the stunt with .035 on spray arc :eek: and short circuit *can* lead to LOF defects. Would a small wire in spray range get you better penetration in the same joint setup?
I realize that this is all theory and many more practical and better ideas exist, So if everyones bored I'll go work on figuring out which pasta I can actually cook.... Whats the kinda that comes in the pastaroni boxes??? Vermiculite? :eek::grin::grin::grin::grin: I thought angel hair was the tiny tig wire... its a pasta too????:eek::yell::twisted:
Clif :smile:
Parent - - By ssbn727 (*****) Date 10-21-2014 22:16 Edited 10-21-2014 22:19
Well Clif in a pinch and with everything all set up beforehand, it can be used to deposit a weld that size but, if you set your parameters right, and make sure your travel speed is fast enough - a 1/8" weld size can be deposited also... Now the average hobby welder will just pull their hairs out while attempting this but real pro can make it happen without breaking a sweat... Better yet, why not use GTAW with a "1/8th diameter electrode, and at least "1/8 diameter filler metal and voila! You got yourself just what you're looking for... Have you tried a 3/32" diameter SMAW electrode instead? I mean these are alternative processes to consider if the job is going to be just a one off doo-hickey...

Now as far as "Pastaroni is concerned, never heard of it... However my preference for pasta is either Barilla, Buitoni or Ronzoni - Suono Bouni  and it's because how well they end up as "Al Dente" cooked pasta... I like Spaghetti, Vermicelli, Bow ties, Shells and love fresh Tortellini... I Don't care for Angel Hair because too many feathers are left after separating between the two if you get my meaning...:lol::yell::twisted::yell::lol::yell::twisted::lol::grin::smile::roll::wink::cool:

As far as suce is concerned, I make my own... I make enough for about a month's worth and bottle it up but, if the word gets out, I gotta come up with all sorts of excuses as to why I can't spare anymore after I gave about half of it away already... That store bought crap is so bad that I wouldn't feed it to a starving animal with all of those nasty preservatives inside... There's nothing better tasting than home cooked pasta sauce and fresh pasta which i used to make also but, ever since I became ill. I don't have the stamina like I used to make the pasta which is physically taxing at times...

The Buitoni brand Agnolotti, Fettuccini, Linguini, and Ravioli & Ravioletti, Tortellini & Tortelloni, all come pretty close to fresh pasta as you can buy at the store and some of their specialty sauces are just as good as fresh made also as long as it's not tomato based... And don't forget about the fresh Parmesan and Pecorino Romano grated cheese also, or you could chip  the shavings from some fresh cheese of the same type... Now I don't know if they have it in your neck of the woods Clif, but it doesn't hurt to ask ... Here's the link Buitoni products:

Once you try this, you'll understand what I mean! Check it out my friend.:grin::wink::cool:

Parent - - By Lawrence (*****) Date 10-22-2014 11:57
This is a fun thread.

Theory:  (Since I have zero experience attempting to run .023 with spray transfer)

As a "theoretical" rule, as GMAW wire size decreases current density increases.  Having said that, the .023 filler is a questionable conductor for currents high enough to make it spray.   As Henry correctly noted, that size was developed for thin gage metal and auto body repair.

A 1/8 fillet...  No problem with .023, .030, .035, and .045  depending on the power supply driving the arc.

In an ongoing production scenario, running spray values with .023 has some very real physical drawbacks
* Cost per pound
* Driving .023 at high feed rates consistently is difficult, especially in manual operations due to it's lack of rigidity. A very short whip would be recommended
* Greater wear on feeders and end consumables forced to work at higher rates

While there is much debate, small diameter FCAW is often used for high production of small fillets (.035)

I recently completed PQR's and weld trials on plain carbon steel and one of our goals was to attempt to produce consistent 3/16" fillets with .052 filler...  This seems a rather small fillet when you look at the wire size, however, we had success with these fillets at linear travel speeds of 28 inches per minute (as fast as you can ask a human to go for a 10 hour day).  We could have easily reached 35 IPM but only a robot could do it consistently.  (The welds were produced with a pretty advanced GMAWP...Sorry Ed Craig)    At over 150 tons of filler used annually for the project, the cost of using a larger bore filler and ensuring correct sized welds becomes relevant.

The "trick" to making a small (1/8") fillet for the welder him/herself is to establish and maintain an arc length that is very short that has enough current density to fuse the root.  Keeping a consistent short spray arc with .023 in a production environment would be challenging in my view, especially where any inconsistency in fit-up would not benefit the smaller wire dia.

Having said all of that, .023 solid wire is great for 16 ga. (.063) and thinner base metals and manual welding. Nothing makes a prettier weld that is semi-automatic.  But if the production volume requirements were high I would look to a larger bore filler wire.

Henry...  My wife LOVES when I do Angel hair,    With about 8 minced garlic cloves.  First I scorch about 4 tablespoons of butter and then add olive oil and the garlic and allow that to simmer about 4 minutes or until it begins to froth.  At that point I put the pasta in water and add a little cream, (or yogurt if we are dieting) to the sauce and just let it get steaming, no need to boil.    Remove pasta and drizzle with olive oil to keep it from sticking and put on plate topped with sauce, chopped tomato and chopped parsley.   Really simple and really powerful if you like the garlic.

You should publish your marinara/Red recipes and variations........ You are making me hungry.
Parent - - By electrode (***) Date 10-22-2014 15:16 Edited 10-22-2014 15:19
first and foremost.
My apologies if you have misunderstood (maybe) a specific sentence in my response to John Wright in that 'Aluminium welding question' thread.
I have edited it, just to clarify what's eventually been confusing to you.

Back on this topic and just in order to better understand.
Do you mean from your practical experience that PlasmaHead2 was using then a "spray arc" by adjusting the parameters he did provide?
Or some sort of "short" spray arc having "a consistent crackling sound"?
Knowing that this is much depending on power supply and so forth.
On the other hand, 10 m/min wire feed speed remain 10 m/min wire feed speed, isn't it?
Btw I also have never used such a small wire diameter under industrial environment conditions.
Really interesting.

Corrected a typo.
Parent - - By Lawrence (*****) Date 10-22-2014 16:10
I was speaking in generalities 

<more voltage=greater arc length>
<less voltage= shorter arc length>

When the arc length is longer, it is more difficult for an operator to place a small fillet... regardless of solid wire size.
Parent - By electrode (***) Date 10-22-2014 16:55
I understand.

Thank you.
Parent - - By ssbn727 (*****) Date 10-23-2014 00:00
I'll write a few up for you that I know you and your wife will enjoy... Do you think Clif understood what I was saying regarding the feathers getting in the way from the Angel's wings?:grin::lol::yell::twisted::smile::wink::cool:I actually do like Angel hair pasta but, only for dishes meant to be with that particular type of pasta... Your recipe reads like a savory one and yet other folks use that sort of pasta to make some - well let's just say questionable combinations of the ingredients they use with Angel hair... I guess I'm a traditionalist when it comes to classic Italian with some dishes... You know now that you mention it, I have a few E-books of Italian cooking that have some excellent recipes from various parts of the country including Sicilian style cooking also... When I locate them I'll send them to you via Google drive okay? Gotta go take my meds... Give me a day or two and I'll send then out to you Larry.

Parent - By PlasmaHead2 (***) Date 10-23-2014 00:56
Check my reply to Lawrence
Parent - - By PlasmaHead2 (***) Date 10-23-2014 00:55
Hey Lawrence,
You hit on a few points that I was pondering on...
"While there is much debate, small diameter FCAW is often used for high production of small fillets (.035)" Was that in  reference to using .035 dual shield flux cores? I remember and article in the welding journal about building some sort of barge for the great lakes; over welding was a concern and they found using a .035 dual shield flux core gave them better results... BUT I cant find the issue and my memory likes to fail me on the details....

Now in regards to travel speed and arc length... how would manipulation of the arc play into this? When I was welding the bits of scrap I use a sharp "v" motion with a rapid forward motion that dragged the arc into the root and then a slight up/down motion that brought the arc to the upper and lower toes and filled the puddle out... forward up down forward up down ect ect...
All motions kept a solid continuous puddle I just varied where the arc was in the puddle...  (if that makes sense?)  On the forward bit of the motion the arc sounded Very smooth and spray like and I could see the bright shiny edge in the base metal as it dug in, but then turned into a "slow" short circuit sound as I completed the V...

Was the change in the arc length on the rapid forward motion shifting the transfer into spray over some form of globular/short circuit? Is that even possible?

This was done with a Millermatic 251... Volts and WFS is all the control it has. I WISH I had inductance control.... :sad:

Your version of angel hair sounds awesome... no feathers:wink::twisted: and Lots of garlic. I Love garlic; the roommates might have to suffer....:evil::evil::twisted::twisted::wink:
Parent - - By Lawrence (*****) Date 10-23-2014 12:04 Edited 10-23-2014 12:07
Great question about what happens as the arc moves to various parts of the puddle.

I only have opinions, and most of those are based on training hundreds of students (and now professionals) who all want to "whip" the gun and make pretty welds.

For me it all comes down to the size of the gun manipulations (assuming you are looking for max fusion)...  If the operator limits gun/electrode motions to the front third of the puddle, attempting to stay near the leading edge, the weld is probably going to be fine.  But when the operator whips the gun into the back third of the puddle, where the deposited metal has built-up a cushion, fusion is reduced.

I see stringers that consistently pass destructive testing (guided bends and fillet breaks) and I see whipped welds being much more inconsistent in passing the same tests.  And I'm talking thousands of tests.

Also with side to side motions, if the operator is going quickly forward with a side to side motion, it's likely that sidewall fusion or fusion at the toes will be an issue.

Any motion, whether side to side or forward and back is going to make it take longer to get from A---->B   And in a world based on production rates this cannot be a good thing.  I'm a big advocate of creating parameters that encourage a straight GMAW stringer.  Now an operator can "wiggle" that gun one or two electrode diameters to spread out the toes of the puddle, we aren't robots eh?    But excessive motion in my experience leads to overwelding of fillets and fusion defects.
Parent - By ssbn727 (*****) Date 10-23-2014 12:54
I agree wholeheartedly Larry!:grin::lol::cool:

"Pretty pattern" whipped GMA Welds are nice to look @ but what good is it to end up having to re-weld a good portion of the joint because the welds didn't pass NDT with the exception of visual and possibly LPT... And let's not forget all of the stress risers left in the weld face from all of that whipping... Stringers are the safe bet IMHO.:roll::surprised::grin::cool:

Parent - By jwright650 (*****) Date 10-23-2014 13:45

>I see stringers that consistently pass destructive testing (guided bends and fillet breaks) and I see whipped welds being much more inconsistent in passing the same tests.  And I'm talking thousands of tests.

Same here Lawrence......I have found the same results over thousands of coupons tested. Beit GMAW or FCAW, whipping produces inconsistent penetration/fusion at the side walls and/or additional passes and at the root vs straight stringers.
Parent - - By welderbrent (*****) Date 10-23-2014 15:33
I appreciate the distinction betwixt 'whipping' and 'wiggle' of the electrode.  I would whole heartedly agree that regardless of process, base material, etc the 'whipping' is an overrated 'look' that doesn't pan out in quality nor quantity. 

I believe part of the problem is those who have been told their 6010, 6011, as well as GTAW and other processes need to have that 'stack of dimes' look.  Seldom is that the best way and even when it is it must be done with great care to make sure of no lack of fusion, trapped slag, or other discontinuities.

He Is In Control, Have a Great Day,  Brent
Parent - By Lawrence (*****) Date 10-23-2014 15:42
Before I do destructive testing I will tell the group:   It's hard to argue with success. But if you don't succeed, you better get the wax out of your ears.
Parent - By PlasmaHead2 (***) Date 10-24-2014 21:29
So the general consensus is that motion in the ocean can lead to issues unless you have an Au based appendage... Sound about right? :twisted:
Parent - By Metarinka (****) Date 10-23-2014 21:03
very great post lawrence.  I do have some experience trying to top out thin gauge gmaw wire and develop parameters.

You also have to remember that on most non CNC machines WFS and current are not completely decoupled.  You can't feed enough wire feed at 0.023" to get a stable spray transfer as you'll be shooting through your current density in order to try to maintain a reasonable amount of fill.   If you look at parameter ranges 0.035" wire would be preferred as it can still enter spray at relatively low heat inputs but won't requires as much WFS to get a proper fill volume.  Still I recall tuning welders to 400-600 IPM of wire on 0.035" spray which is very heavy.  As mentioned one twist in a liner with 0.023" and it will bird nest or burn back.
Parent - By PlasmaHead2 (***) Date 10-22-2014 23:58
Hey Henry,
Well if I want to "Cheat" then of course I can use GTAW...:wink::wink::wink::twisted::twisted::lol::lol: I'm trying to play "how can I do it with GMAW" :wink::wink: And its all theory, I barely have the occasion to use the .023 wire for its proper uses, let alone for the wild ideas I came up with... :wink::lol:
Most of the work I do is one offs/ very small batch so most of it is GTAW to avoid the fuss and mess of GMAW.

I'll give a hunt through the local food stores... Im sure one will have that buitoni brand. Then Ill get my roommates to cook it because according to them I cant cook... :grin::grin::grin::lol:
They told me to sear a steak one time... SO I grabbed the rose bud and asked how black did they want it? They both face palmed and told me to get out of the kitchen.... :yell::yell::twisted::twisted::lol::lol::twisted:
Oh and pastaroni would be barely edible swill of the masses compared to actual pasta and homemade sauces, but its really easy to cook and doesn't taste completely awful.... :lol::lol:
Parent - - By Metarinka (****) Date 10-23-2014 21:07
I'm replying to your post because it's convenient Henry,

It should be noted that the cross section area of 0.023" wire is half that of 0.035" wire (0.0009 sq in vs 0.0004 sq in")   area goes up exponentially with dimeter so even that extra few thousands doubles the area.   The current density starts going through the roof on 0.023" wire on a CV machine when you start pushing the WFS.

also I would be worried about minimum weld size and cracking if running really small hot stringers with 0.023" on thicker cross sections.
Parent - - By ssbn727 (*****) Date 10-24-2014 15:45 Edited 10-24-2014 16:44
I certainly agree Joel...
I forgot to mention another application for .023 Dia. CS wire... Using it to cold wire GTAW thin sheet metal CS... Just a thought...

Btw, where are you today? I ask this because you have been quite the traveler this year.

Parent - - By electrode (***) Date 10-24-2014 16:30
That's still confusing.
Which (arc mode) was it then, that PlasmaHead2 was using? I was under the impression that he was estimating it quite suitable - even for replacing higher diameter wire electrodes.
ø ~ 0.6 mm at ~ 10 m/min wire feed speed? Hardly conceivable that these data may provide you with regular "short arc" output.
Apart from that of course, further information on shielding gas(es) used might prove beneficial.
Parent - - By PlasmaHead2 (***) Date 10-24-2014 21:22
Hey electrode,
it was a c25 blend, 75%Ar 25% Co2. Not sure of the flow rate at the moment, ill look tommrow, but I know it wasnt up high enough for spray.
The weld I made at the settings listed was Not in the spray transfer range, it seemed some where in between the hot end of short circuit and globular... but the end result was missing the giant spatter filled mess that globular ends up with. It ALMOST seemed like the wire was globbing up but it was forced into the puddle before it could go haywire and make a mess....
Parent - - By Superflux (****) Date 10-24-2014 21:41
I've never had good luck on spatter control with 75/25 on spray mode.
I do believe there should be some better recipes out there.
Parent - By PlasmaHead2 (***) Date 10-24-2014 22:44
I'm with ya... I want a bottle of 98/2 Ar/O2 or something along those lines....
Parent - - By Lawrence (*****) Date 10-25-2014 01:57
75/25 will not spray with 023 wire ever... It's impossible
Parent - By PlasmaHead2 (***) Date 10-25-2014 02:13
how about pure Ar?
Parent - - By electrode (***) Date 10-25-2014 10:03
first of all, thank you for responding.
I suppose that you have opened a can of worms here - much appreciated.
An interesting topic - that is to say, because it approaches some questions that I (personally) have never been thinking about as yet.
We had already a brief initial discussion on "whooshing" arcs, as appropriately put by Lawrence the other day.
This "whooshing" has been observed and - understandably - studied of course some decades ago.
It was agreed among the 'experts' being a function of the current density (without having - even rudimentarily - discussed what that actually means in terms of GMAW). It's a number relatively good to recall (for me) and its evaluation is going back to using coal electrodes for establishing and maintaining the arc plasma. Hence, the "whooshing" appears at ~ 40A/cm² for disappearing again at higher current densities.

Apart from that, I suggest you mean carbon dioxide while writing "Co2". I am honestly not sure whether the gas flow rate is much affecting the droplet transfer regime (e.g. spray transfer) or whether this is - in that particular respect - a rather negligible parameter.

There are 3 questions arising and I'm afraid that the 2nd of which is directed to Lawrence rather:

1. As you say "...It ALMOST seemed like the wire was globbing up but it was forced into the puddle...". Is the arc 'digging' underneath the surface allowing the droplet(s) to be accelerated towards the weld pool bottom?
2. Lawrence says: "75/25 will not spray with 023 wire ever... It's impossible". Just out of real curiosity; 'why' is this impossible? Is this statement based mainly upon the shielding gas deployed (25% carbon dioxide + argon as the remainder)?

Please note again. I myself have never used such small wire electrodes yet.
Then, finally, in connection to question '2'.

3. From your response I presume that it was definitely not a "whooshing" arc?

Thank you again.
Parent - - By Lawrence (*****) Date 10-25-2014 12:08 Edited 10-25-2014 12:12
I cannot explain the physics, but trials have shown that 25% carbon dioxide is just too much active gas to produce spray transfer with that wire size.

With .045 wire and 75/25 it takes upwards of 34 volts to achieve true axial spray and .035 won't do it at any voltage.

Anybody with a CV Power supply can try this... 

Also this shows me you did not read every word on Ed Craig's website, because he covers this thoroughly :)
Parent - By electrode (***) Date 10-25-2014 12:45
"Also this shows me you did not read every word on Ed Craig's website, because he covers this thoroughly".

LOL! :)

May you forgive me ... but I'll need to confess: "I was lost in the challenging vastness of Mr Craig's commentaries and exemplifications."
I was literally forced e.g. to read about the Beijing Olympic Stadium and the poor weld quality produced there - without, however, and as a matter of fact, having seen a single welded joint.
Anyway. Thanks for the reply, which certainly makes sense to me.
It would be fine finally to reveal the true character of the transfer mode that PlasmaHead2 has generated, by adjusting the weld parameters just as he did.

Thanks again, Lawrence.
Parent - - By PlasmaHead2 (***) Date 10-26-2014 16:24
Hey electrode,
I was trying to open up a can or 2... Mission Accomplished :twisted::twisted:

1: Nope, it wasn't that forceful. I believe you are describing buried arc transfer... something I've only read about and would only want to see once. Very spattery....Also required was 100% Co2... This seemed more like the speed of the wire was driving the molten blob to the top of the pool before it got too big and unstable.
2: I know I need to spend more time on Mr. Craigs site.... :lol:
3: Nope, no stable "woosh" noise... only slightly with the motions I was making. The weld in question was only about an inch long.... didn't give me much of a chance to observe what was going on.

I tried to get it all rigged up again but everyone else in the shop gave up and went home. We have to have 2 people in the shop at all times... so no playtime this week.

For now I'm going to convince the boss that we need a bottle of some high argon mixed gas...
Parent - - By electrode (***) Date 10-26-2014 17:09
I seem to understand; thank you PlasmaHead2.
~ 1 inch. That's not much, indeed.
But for that rather short bead you've obtained quite high efficiency along this thread - approaching 2 posts/mm bead length.

Anyway, and with all due respect. There is nothing existing/standardised such as a "buried arc transfer".
Actually you may achieve such a 'buried arc' behaviour through rising the weld current (in correspondence to the wire feed speed), even with argon + higher carbon dioxide blends.
That is exactly how I understand Mr Craig (quote) "when he says the best GMAW Spray transfer weld should have a consistent crackling sound". [1]
So, in my opinion, a GMAW spray arc can show this burying character, and the "crackling sound" can arise from short circuits that last an extraordinary (what ever in a technical sense that means) short time only.

Apparently you have generated something really interesting here, PlasmaHead2.
I for one am not aware as yet of any research dealing with such small diameter wire electrodes connected to such high wire feed speeds.

Parent - By PlasmaHead2 (***) Date 10-26-2014 18:02
You are correct about the non standard term, thats all I've read about it as.

I have some edition of that book in my library, and I believe its in one or 2 of my other text books. I've never attempted such a process before, from the descriptions it would work best in some sort of automated set up. Also the spatter I was referencing seems to be if you get it wrong... whoops.
It seems to get lumped in with globular transfer... I have seen a drawing of the process that I cant find online which showed that the wire makes a "arc/vapor" cavity below the surface of the plate/puddle. It had a slight resemblance to a PAW Keyhole weld in thick plates(only seen pictures :sad:); a round hole from the plasma stream with a space in front of the hole being molten.
Parent - - By ssbn727 (*****) Date 10-27-2014 00:11
Ummm There sure is a whole lot of confusion regarding this method of transfer called the Buried Arc method of transfer with GMAW or is it a method of transfer and not a process, or is it a technique? Hmmm... The problem with this method of transfer/process/technique is that it's use isn't widespread because of it's limitations... Quote: "The resultant welds tend to be more highly crowned than those produced with open arcs. But they are relatively free of spatter and offer a decided advantage of welding speed. These characteristics make the Buried Arc process? useful for high speed mechanized welding of thin sections, such as that found in compressor domes for hermetic air-conditioning and refrigeration equipment for automotive components.

Because carbon dioxide is an oxidizing gas, it's application to welding carbon steels are restricted. It cannot be used to fabricate most non-ferrous metals. Neither should it be used to weld stainless steel because carbon corrodes the weld metal. Carbon dioxide and helium are similar in that metal transfer in both gases is globular. Helium too can be used with the buried arc technique? (What is it, a method of metal transfer, or is it a process, or is it a technique?) It has the advantage of inertness, potentially making it useful for the same types of applications as carbon dioxide but in non-ferrous alloys." Unquote...

Well folks what do you think it is... Is it a method of metal transfer? A process? Or is it a technique? I think it's a technique because it has already been written that the process is GMAW, and it has also been noted as being a globular method of metal transfer... So the only one it could be is a technique logically speaking of course... But you know how that goes sometimes with welding terminology... Anywho, let me know what the rest of you think the buried arc? should be designated as.

Parent - - By electrode (***) Date 10-27-2014 16:32
thank you.

Very well.
Now slowly but surely it becomes really interesting possibly confirming what I was saying, i.e. PlasmaHead2 may have opened a can of worms.

Supposedly it is necessary to distinguish between theory - steering the "spray arc", and practice - applying it. It presumably will be difficult to deal with the former in an appropriate manner mainly due to both, lack of time and visualisation means on this forum (inserting expressions etc.). The latter, however, should be possible to have a closer look at.

The first time I personally could read about welding arcs acting underneath the workpiece surface was in close conjunction to Plasma Arc 'Keyhole' Welding; as well as not to forget, high current GTAW. As so often specific boundary conditions lead to obtain a physical status forcing the molten weld pool in a predictable way. That is, shaping some sort of cavity; or, as I described it in another post just recently, some sort of "channel" (which I suggest describes it more appropriately) of finite dimensions and showing similar behaviour as the well-known phenomenon in laser keyhole welding. And as such your finding/statement/question that: "There sure is a whole lot of confusion regarding this method of transfer called the Buried Arc method of transfer with GMAW or is it a method of transfer and not a process, or is it a technique?" appears reasonable, maybe even overdue.

Fortunately we apparently always run across the same physical effects - and I do very much like that, does it yet allow to predict results – in part at least. Such as Lawrence has made use of Mr Craig's recommendation that a "crackling sound" spray arc should be preferred versus a "whooshing" one. So, varying some experimental conditions while maintaining others constant we can achieve a spray arc either "whooshing" or "crackling". I heavily suppose that PlasmaHead2 will find exactly that when he's going to change his shielding gas from high carbon dioxide to maybe oxygen containing. That being said - and in order to try to answer your question. If memory serves me correctly, it were the Germans; i.e. their DIN 1910-Part 4, a number of years ago classifying a "buried arc" besides short-, spray- and pulsed arc. This sort of transfer was achieved (mainy) under pure carbon dioxide and the droplet transfer was - as conceivable - strongly affected by repelling effects. That however, at least in my understanding, is different from what's being described by Mr Craig's "crackling" spray arc, because droplets of considerable mass are mainly transferred as a result of gravity.

I myself consider the "crackling" spray arc as being the result of a "high-current" (independent of what that means in this conjunction) affected wire electrode, forming a liquefied taper being split again into a higher number of smaller droplets which may or may even not short circuit with the weld pool cavity's - or channel's - bottom/walls. These (brief) short circuits make Mr Craig's spray arc so typically "crackling" and its welding behaviour so preferable. All that however, is part of specific conditions chosen by the user, mainly, by deploying shielding gas(es) with higher carbon dioxide contents. Maintaining all conditions constant and just changing the shielding gas to e.g. containing oxygen instead of carbon dioxide leads the arc to (mainly) work above the workpiece surface to split the liquefied taper into droplets before short circuiting with the weld pool. This, to me, is Mr Craig's "whooshing" spray arc, negatively joined by humping effects, undercuts, etc. etc.

Of course you're right when you now say that this is the very basics; but, as aforementioned, further to approach the most interesting theory behind that is something, requiring much more time and unfortunately there's always considerable lack of the latter.

Hence, to briefly summarise and answer your questions:

1.  Is it a method of metal transfer?
Negative (to me). But it affects the metal transfer.
2.  Is it a process?
Negative (to me). Maybe a result rather of specific physical boundary conditions.
3.  Is it a technique?
Yes (to me), if you want it that way. Because it is on you only to choose and set up the boundary conditions to beneficially use the "buried arc" for meeting specific requirements.
Parent - - By Lawrence (*****) Date 10-27-2014 16:49 Edited 10-27-2014 16:58
I'm going to stick with my guns on the "crackling" arc.  It's simply shorter, via less arc voltage.

Meaning this: (in a practical scenario I have demonstrated uncounted times)

1.    Set GMAW for spray on base metal with some thin mill scale with a long arc (spray meaning an open arc with droplets smaller than the electrode wire, being pulled axially into the pool by electromagnetic forces)   This will make the "whooshing sound"

2.  Reduce voltage until crackle is heard, but an open arc with the pinch effect is still clearly visible, and the weld is still spatter free (this is easy to do with oxygen mixes)

3.  Grind off mill scale (not sand, grind) and make weld again with "crackle" parameters.  You will find the noise is gone and the arc is slightly longer visibly.

4.  Realize the arc is much more easy to control and is still open and visible (not buried)

5.  Anybody who does GMAW performance testing on a regular basis will hear the ring of truth in this... Meaning, a V-groove weld test assembly with ground or machined bevels and a ground backing bar will use slightly less voltage than production parameters on the same materials with mill scale.  If the voltage is not reduced slightly during testing (1/2 to 1.5 volts, within WPS values), undercut on the toes is often evident.  It's just the way it works guys.

Buried ARC and Dip-spray transfer are two different modes.

Dip Spray
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