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View Full Version : Why cant my mig be this nice???



fordman
02-12-2008, 03:28 AM
I was just doing some browsing and saw this. It seems like whatever I do, with my new welder I cannot produce a nice concave bead! I am defintely not confident with my welds with that welder, nothing feels right! The digital aspect of my welder is the only thing I can think of that is throwing me off, its rediculous.. I may end up selling it for a new miller 210 or something? :realmad:

16661

Dmaxer
02-12-2008, 04:32 AM
I was just doing some browsing and saw this. It seems like whatever I do, with my new welder I cannot produce a nice concave bead! I am defintely not confident with my welds with that welder, nothing feels right! The digital aspect of my welder is the only thing I can think of that is throwing me off, its rediculous.. I may end up selling it for a new miller 210 or something? :realmad:

16661

Tried your link and it didn't work. Sorry!

jamlit
02-12-2008, 04:37 AM
I fixed your post so the picture showed up fordman

I think the weld in the pic is tigged. You can get close to that look with mig. Pulse mig will give you a similar look as well as the technique used with a regular mig. ZTFab told me to use a circular motion while welding. I found this to work fairly well for me but I liked the fact that I was moving the arc onto fresh metal and getting great penetration then reinforcing the weld I just laid down. Also the push pull method can cause this. Spending money on a new welding most likely will not help.

olddad
02-12-2008, 04:54 AM
That looks like it came out of a positioner...you'll never match that by hand.

Dmaxer
02-12-2008, 05:21 AM
Oops, just after I posted above, the photo appeared. I don't understand why I couldn't see it before.

That photo, if it's of a MIG weld trying to look like a TIG weld, has to be the result of the weldor's hand motion (up and back, aka stitch motion). There's more to it for sure if you're not a pro. Perfect settings on the proper machine for the material are necessary and the result of practice, practice, practice. I used to have a link to a welding video showing the motion, but can't find it now.

David R
02-12-2008, 07:32 AM
Pulsed MIG will not make that look. Its the nut behind the wheel. The man holding the mig gun makes those dime like beads. More heat, pretty quick motion. Circular, or ahead and back depending on the situation. It can be done, but......Not necessary. Forehand is the first thing that comes to mind. If you do any kind of weave, you need more heat especially circular motion. Concave bead..... not good. A bead should be flat across the top to be the strongest. Anything more than that (convex) is wasted metal. If the puddle is hot enough, a back and forth or a UUUUU motion can result in that look too.

Olddad is right on, it was done on a positioner, probably vertical up or some where between that and flat.

Forehand, flatter bead less penetration. Backhand (pull) deeper penetration, taller narrower bead.

I don't need no stinkin dimes!

David

-olllllllo-
02-12-2008, 09:30 AM
done a few things in my life that compare to the skill required to make that weld. two off the top of my head are cake decorating, and tattooing.

littlefuzz
02-12-2008, 10:25 AM
It's a mig bead in the pic.


Pulsed MIG will not make that look. Its the nut behind the wheel. The man holding the mig gun makes those dime like beads. More heat, pretty quick motion. Circular, or ahead and back depending on the situation. It can be done, but......Not necessary. Forehand is the first thing that comes to mind. If you do any kind of weave, you need more heat especially circular motion. Concave bead..... not good. A bead should be flat across the top to be the strongest. Anything more than that (convex) is wasted metal. If the puddle is hot enough, a back and forth or a UUUUU motion can result in that look too.

Olddad is right on, it was done on a positioner, probably vertical up or some where between that and flat.

Forehand, flatter bead less penetration. Backhand (pull) deeper penetration, taller narrower bead.

I don't need no stinkin dimes!

David

Don't be hatin just cause you can't do it :p

badassb5.5
02-12-2008, 11:02 AM
I fixed your post so the picture showed up fordman

I think the weld in the pic is tigged. You can get close to that look with mig. Pulse mig will give you a similar look as well as the technique used with a regular mig. ZTFab told me to use a circular motion while welding. I found this to work fairly well for me but I liked the fact that I was moving the arc onto fresh metal and getting great penetration then reinforcing the weld I just laid down. Also the push pull method can cause this. Spending money on a new welding most likely will not help.

Yep I would agree. If that isn't tig that has to be the cleanest mig weld I've ever seen. But still a damn nice weld... Very nice:)

tommyj3
02-12-2008, 11:26 AM
That's definitely a mig weld done in a horizontal positioner. Very nice weld indeed.

gnm109
02-12-2008, 11:31 AM
I say it's a TIG weld done in a positioner. That's my story and I'm stickin' to it. :cool2:

MXtras
02-12-2008, 04:05 PM
I say MIG. You can see the small amount of crap at the crest of each bead.

This can be done easily with smaller diameter wire and a consistent forward, pause, forward, pause motion.

Scott

David R
02-12-2008, 06:34 PM
When I get my positioner, I'll try it. No idea when that will be.

David :)

olddad
02-12-2008, 06:39 PM
This can be done easily with smaller diameter wire and a consistent forward, pause, forward, pause motion.

Scott
Yep, but like David R pointed out, a smooth face is stronger...it'll be purty once it's wire buffed though.
Start the bead just before it rolls over the top and it sets up "OOO SO NICE"

turboblown
02-12-2008, 10:26 PM
That is certainly MIG on a positioner with a consistant rotation speed on the shaft while making the weld.


If you've ever been in a driveshaft shop and watched the process, that's exactly what it looks like with MIG. These shops have it down to a science. And yes- it looks like that without pulse. I used to be at the shaft shop once a month when I was a psycho 4 wheeler in my 79 Dodge Sno-Commander.

paintman
02-12-2008, 11:51 PM
i have a miller 210 and i cant match that bead,its probably someone way better at welding than me

tanglediver
02-13-2008, 12:50 AM
That is certainly MIG on a positioner with a consistant rotation speed on the shaft while making the weld.


If you've ever been in a driveshaft shop and watched the process, that's exactly what it looks like with MIG. These shops have it down to a science. And yes- it looks like that without pulse. I used to be at the shaft shop once a month when I was a psycho 4 wheeler in my 79 Dodge Sno-Commander.

I concur, the weld is mig. The photo is deceiving in size. Really nice! :cool2:

fordman
02-13-2008, 01:58 AM
Here is the piece getting welded. http://pirate4x4.com/tech/harry/twisted_customs/07welding.jpg Looks good to me, I am pretty sure its MIG

dad
02-13-2008, 03:14 AM
I agree about the bead having to be AT LEAST flat. I however think that a small convex, is the best. I agree that you don't need to over weld; with a larger convex on most things. I also think that a continuous weld bead would be stronger than the stack of dimes.

littlefuzz
02-13-2008, 03:29 AM
I also think that a continuous weld bead would be stronger than the stack of dimes.

The "stack of dimes" is continuous. Only the dumbazz "weldors" do the tack method. Maybe the tack method is good on some real thin material but not on anything structual.

mb_welder
02-13-2008, 08:13 AM
I've worked in shops where all they know is the tack method...mainy for 3G welds. Suffice to say, I don't work in those shops anymore. Nothing says "Farm code" like zap...zap...zap... (no relation to the person, lol!) :rolleyes:

Hell, I worked in a shop where they would zap tack uphill with metalcore, then downhill a metalcore weld overtop. In that shop, I pulled teeth to get an all position wire for all the uphill stuff, and the metalcore monkeys there didn't even show an interest in learning how to use it...fun stuff.

littlefuzz
02-13-2008, 08:55 AM
There's no telling how many people actually "weld" with this method on structural stuff just because they think that's the way you get the stack of dimes appearance. I would bet there are several here at this site that do, but I would also bet no one would admit it.

enlpck
02-13-2008, 10:36 AM
Slight convex is desirable. Concave is not. If you want a concave surface for cosmetic reasons or for load distribution, reprofile after the completion of welding by either grinding or machining.

See fig 4 (page 3) http://content.lincolnelectric.com/pdfs/knowledge/articles/content/weldcracking.pdf

turboblown
02-13-2008, 07:18 PM
I just don't understand why everyone wants the "dimes look" on critical or structural items.

It looks nice in some places like running and step boards, truck tool boxes and other cosmetic areas, but to me a weld that penetrates and is solid is what matters.

You want to see some schitty looking welds that are strong? Look into any stock car that runs in a sanctioned class all the way up to NASCAR.

dad
02-13-2008, 07:22 PM
The "stack of dimes" is continuous. Only the dumbazz "weldors" do the tack method. Maybe the tack method is good on some real thin material but not on anything structual.

Maybe I used the wrong word. I realize that it is a continuous bead ( not tack after tack ). What I'm saying is that the stack of dimes comprimizes weld integrity, versus, a uniform bead, with no low and high spots, that makes the stack look. I know, people do it every, but bottom line is it is weaker. Kinda like a concave is typically weaker than a convex bead, as long as it isn't over welded.

Go1lum
02-13-2008, 08:57 PM
Maybe I used the wrong word. I realize that it is a continuous bead ( not tack after tack ). What I'm saying is that the stack of dimes comprimizes weld integrity, versus, a uniform bead, with no low and high spots, that makes the stack look. I know, people do it every, but bottom line is it is weaker. Kinda like a concave is typically weaker than a convex bead, as long as it isn't over welded.

have you done test to prove this accuization because i disagree.

lewray
02-13-2008, 10:08 PM
I think I see the "glassed look" of the argon around the face and root sometimes seen in GMAW aka mig lol.

At first I thought no way, but yeah I'll bet its mig. Thats pretty dang good.:cool2:

Zap your opinion?

David R
02-13-2008, 10:12 PM
have you done test to prove this accuization because i disagree.

2. Poor Torch Oscillation: If a welder
makes “little circles” with the torch, it is
easier to make a pretty bead, but there is
a good chance for lack of fusion. As the
torch moves back into the puddle, the
molten metal doesn’t stop and wait. It
continues to advance, but without the
benefit of the intense heat of the arc to
melt the base metal. The puddle just lies
on top of the work instead of fusing to it.
Exaggerated oscillation produces the
same problem.


I got this here http://www.prest-o-sales.com/other_links/gases/PDF/ShieldingGases/Manuals/GMAW%20of%20Carbon%20Steel.pdf

lewray
02-13-2008, 10:22 PM
2. Poor Torch Oscillation: If a welder
makes “little circles” with the torch, it is
easier to make a pretty bead, but there is
a good chance for lack of fusion. As the
torch moves back into the puddle, the
molten metal doesn’t stop and wait. It
continues to advance, but without the
benefit of the intense heat of the arc to
melt the base metal. The puddle just lies
on top of the work instead of fusing to it.
Exaggerated oscillation produces the
same problem.


I got this here http://www.prest-o-sales.com/other_links/gases/PDF/ShieldingGases/Manuals/GMAW%20of%20Carbon%20Steel.pdf


David I disagree with only 5% of your opinions...however man that makes great sense I never thought of it that way.:cool2:

David R
02-13-2008, 10:23 PM
Today I was welding some pipes to flanges. 3 1/2" pipe OD to a 1 1/4" thick flange on the outside. I have a hand powered :) positioner that is nothing more than an axle off a trailer.

While doing one, Instead of turning the piece in a nice smooth motion, I wiggled it back and forth a little to get that dime look. I could see with my own eyes the weld wasn't as good because the wire was not directed in the root of the weld at all times. It was going back into the puddle. I got a pretty weld, but......

dimes
16718

No dimes
16719

David

David R
02-13-2008, 10:26 PM
David I disagree with only 5% of your opinions...however man that makes great sense I never thought of it that way.:cool2:

If we all agreed, this would be a boring place!

David :)

Black Wolf
02-13-2008, 11:11 PM
Whoever started this "Stack of Dimes" crap should be shot & whizzed on.

GMAW (Mig) welds should look like GMAW welds.

GTAW (Tig) welds look like GTAW welds - Totally different.

Trying to make a GMAW weld LOOK like GTAW = Start/Stop/Start/Stop weld that is not as strong as it should/could be.

I'm leaning towards the group that identifies this as a GMAW (Mig) weld because I can see silicon islands on the deposits. Now, if this is a GMAW weld, it is stretched out & sloppy, the pattern should be much tighter, but the operator was trying for the "Stack of Dimes" look. :realmad::realmad::realmad:

IF this is a GTAW (Tig) weld, then it is even sloppier, and the weldor needs to be retrained 'cause that pattern is just WRONG and reminds me of a girl I used to know.....Loose & Sloppy & embarrasing to be seen with in the daylight.:blush2::blush2::blush2:

Weld bead profiles should be flat to slightly convex for re-inforcement...We're talking the thickness of a dime or two here - No wasted metal.

Opinions vary. This is mine.

Go1lum
02-13-2008, 11:11 PM
David it's all about proper technique and settings. I can do a weld getting a stack of dimes that holds up in destructive testing just as good as a plain strait bead.

enlpck
02-13-2008, 11:49 PM
problems with 'stack of dimes' welds (no matter what the process):

Each dime comes with its very own stress riser. Under some conditions of loading, this is a place for cracking to start.

The dimes come with concave sections at the edges. The surface of the weld metal is placed in greater tension as the weld cools than a flat to convex profile, and is more likely to crack, especially as the greatest tension often occurs at the centerline where other properties of the weld make cracking most likely.

With some processes, the dimes come as a result of technique that can lead to good fusion (TIG, or 6010 stick), other processes they come as a result of technique that can be detrimental to good fusion (MIG)


There is no inherent benefit to a weld that has this look, and there are often drawbacks. Will the weld be 'weaker' (easy word, but not one with a precise definition without further context)? Not necessarily, but often.

CaptainWilly
02-14-2008, 01:15 AM
my mig welding teacher yells at me for welds like this for no other reason than the fact it doesnt look like a stack of dimes... I try but I'm not that good yet so it just makes me weld even worse and no ones given me a straight answer on why I'm suppose to be doing it.

littlefuzz
02-14-2008, 03:40 AM
dimes
16718



David


Uh, I don't see no dimes there :rolleyes:

Everyone has their own opinions but I've been doing these welds for years on everything from 10ga.-1" plate and have never had a failure. These welds have been x-rayed and destruction tested with no problems. Yall do and say whatever you want, it don't make a fuk to me :rolleyes:


Just to be clear I'm not saying if it don't have the stack of dimes it's not a good weld. I'm just saying that's the way I do most of mine.

mat
02-14-2008, 04:21 AM
You're all amateurs :nono: , this is one of mine. (MIG)

http://img405.imageshack.us/img405/8613/photo1058oh2.jpg

wello
02-14-2008, 06:42 AM
my mig welding teacher yells at me for welds like this for no other reason than the fact it doesnt look like a stack of dimes... I try but I'm not that good yet so it just makes me weld even worse and no ones given me a straight answer on why I'm suppose to be doing it.

do your welds the way that is best for you it looks like your going good
everyone has there own way they like there welds
some like a stack of coins (we don't have dimes here :p) some like nice smooth welds
me I like nice and smooth like this one on a beam I had to make up
each to there own
16727

David R
02-14-2008, 07:25 AM
This is a result of filling a gap. It was a back and forth weave. Its just the way it comes out. the ripples are on the surface, the puddle was quite hot and fluid.

The stringer on the left is just that.

16728

I just make my welds for strength.

David

tommyj3
02-14-2008, 10:27 AM
my mig welding teacher yells at me for welds like this for no other reason than the fact it doesnt look like a stack of dimes... I try but I'm not that good yet so it just makes me weld even worse and no ones given me a straight answer on why I'm suppose to be doing it.

I think your welding teacher needs a refresher course in mig welding. There is nothing wrong with your welds.

Mat and Wello:
Both of your welds are great examples of what a mig weld should look like!

Go1lum
02-14-2008, 12:32 PM
Problem solved how about we all keep doing what we've been doing for years. Obviously all of our individual techniques are working because no one has died yet that I've heard of. I'll do it my way and you do it your way.

olddad
02-14-2008, 01:25 PM
CaptainWilly, might your instructor have been talking about the little bit of sag, or maybe the stop/start in the center ?? As for your bead it looks good, the sag is barely noticable and the restart can be eliminated by learning to shuffle your feet. If in fact your instructor really does have a problem over the "stack of dimes" BS then he needs to do some tech reading !!

Wello, that's the best looking/strongest bead on the page !!

David R, your's look like most experienced mig welders. Absolutely nothing structurally wrong with them. They look like something I might have done. Purty don't make them better and is not needed unless it's called for and paid for. I'd rather burn rod than wire though...too many years of trigger monkey burnt me out...lol.

David R
02-14-2008, 06:27 PM
I guess its just a pet peeve of mine. I see quite a few new guys here trying to make their mig look like a tig weld when what they really need is a good strong solid weld. I get paid for strong not pretty. I want my welds to hold. That is all there is to it. And thank you Olddad.

Mat, my daughter took 3 years of welding in high school. It was stick only. Her teacher used to say "I want to see C's not V's. I never understood that because the heat is hotter and you are going faster leaving a wake like a motor boat. I agree with Olddad, yours and Wello's look great to me. If I am going to use a circular weave, I have to turn the heat way up because the mig gun is moving a lot faster, then I can weld faster....Put more metal down in less time. With more heat Its fine to me. Some of my jobs are piece work. I like to play "Beat the clock". Put down more metal in less time = more $ in my pocket. I still need the best weld I can produce.

David :)

Maybe we can put this one to rest ..... for now.

littlefuzz
02-14-2008, 10:23 PM
I think all of us welders strive for strength in our welds, or at least should. My welds have to be strong (some of the components hold up hanging mezanines) and they also have to look good. I get paid to for strength and looks, if it won't hold or don't look good it don't go out the door!

I agree there's nothing wrong with Wello's bead, it looks great. I run mine like that on some stuff but there's also times when I prefer doing it other ways. Yall don't weld EVERYTHING exactly the same, do ya? Of course not, we all use different methods from time to time. If everyone done everything the same none of these welding forums would be here.

wello
02-15-2008, 05:09 AM
I think all of us welders strive for strength in our welds, or at least should. My welds have to be strong (some of the components hold up hanging mezanines) and they also have to look good. I get paid to for strength and looks, if it won't hold or don't look good it don't go out the door!

I agree there's nothing wrong with Wello's bead, it looks great. I run mine like that on some stuff but there's also times when I prefer doing it other ways. Yall don't weld EVERYTHING exactly the same, do ya? Of course not, we all use different methods from time to time. If everyone done everything the same none of these welding forums would be here.

you hit the nail on the head in your first line littlefuzz
I only post my weld to show how I like them to look and I always do them like that but thats just me

I enjoy looking at Davids work he does great stuff and always keeps us update with what he is doing :cool2:

Shade Tree Welder
02-15-2008, 02:20 PM
Slight convex is desirable. Concave is not. If you want a concave surface for cosmetic reasons or for load distribution, reprofile after the completion of welding by either grinding or machining.http://content.lincolnelectric.com/pdfs/knowledge/articles/content/weldcracking.pdfMaking blanket statements like that is just wrong, as long as your effective throat is equal to or greater than the thinest part being welded, have a concave weld will be the strongest geometry. Having a convex weld will focus all stresses at the toes of the weld.


I just don't understand why everyone wants the "dimes look" on critical or structural items.Me neither.


GMAW (Mig) welds should look like GMAW welds.

GTAW (Tig) welds look like GTAW welds - Totally different.I concur.


my mig welding teacher yells at me for welds like this for no other reason than the fact it doesnt look like a stack of dimes...Your instructor is an idiot, your weld looks good save for the begin is a little cold.


I think your welding teacher needs a refresher course in mig welding. There is nothing wrong with your welds.Amen.