MMA vs GMAW

[super noob]

having this argument with someone....

And as there's obviously some far more skilled welders on here than myself I'll put it to the board!

His argument points;

Stick welding is easy to master which is why anyone can do it

Stick welding is weaker

He can lay down a perfect weld on 12mm plate in one pass, in the wind, using his body to shield the gas from blowing away

Anyone can lay a strong arc weld down but it's harder to mig weld



Mine;

It's 25mph winds

Anyone can point and shoot with a mig but you can have a nice looking bead with no penetration

MMA allows me to lay down runs with full penetration in poor conditions

It'll be a stronger weld than I could do with a mig on the same amps and with the same amount of preheat

There's still a reason you see arc welders used on big steel beams and pipelines





For reference it's 25mm recovery eyes to 5mm bumper plate, pre heated and bevelled the 25mm until it was around 400*

Lay down 5 passes with 1/8th 7018-1 rods in stringer passes followed by 3 weaves to cap it


I'm going to stick one of these in the Denison machine when I get a chance anyway....so I might do a comparative test but what are people's general thoughts?

 

[Woody.v8]

Anyone that says stick welding is easy, Hasn't done any!
I've had this bs from the mig only boys before, My advice is to take loads of no notice and plod on.

 

[super noob]

Haha He hasn't.....his reason was he has a decent £500 mig and knows "mig welding is better/harder" so there's no reason to stick

 

[BrokenBiker]

im on your side, for a given amperage (within hobby welder capabilities) the stick will penetrate deeper than the mig, giving a stronger weld.

also the stick welder will happily weld in horrible conditions, the mig will just give porosity with no gas shielding.

i have never been able to break any of the practice welds i have stick welded, but have broken quite a few of the mig welds i have done as tests (to make sure i had set hot enough, obviously didnt for the ones that broke)

it is harder to stick weld IMO as you have to deal with rod angle, arc length that is constantly trying to change, travel speed, keeping the slag pushed back etc, mig is more point and squirt, if the settings are right then its not hard to lay a decent bead (obviously harder to get a properly good bead) that will hold.

what you should do is get some 10mm steel, set it up in a fillet and put a 3.2 rod in your stick set, 120ish amps and weld the fillet, then tell him to set his machine for full penetration on 3mm (will be not far off the same amps as your stick set) and then tell him to leave the settings alone and weld the 10mm fillet up with a stringer, then batter them both and see which one breaks...i can guess which one will hold better (i happen to know that a bit of 10mm welded with a 3.2 6013 will take 22 ton...Richard on here did the test for me before i welded up a frame for a small press, http://www.mig-welding.co.uk/forum/threads/multi-pass-mig-welds.57847/ this post goes into quite a bit of detail regarding this very arguement...)

 

[Maker]

He seems to think mig is "better" because it's harder. Sub-Arc is even harder by hand*, so I suppose that's even better then?

I think both processes (Done properly) could create an equally strong weld but one will have more heat input, which may lessen the structural properties of the base material, thus being weaker. I don't know what settings each process would require, but someone who does could tell you the heat input for each.

*I'm guessing. AFIAK it's never actually been done by hand.

 

[BrokenBiker]

You could just set your stick welder at about 120amps, put a 2.5 in it and tell him to show you how easy stick welding is...if he can get a good bead from that then maybe he is good at it

 

[Woody.v8]

I have done a fair bit in both processes and although i tend to use mig for speed and ease of clean up, I still lean towards mma for a proper strong joint as i was trained and brought up with stick i seam to be able to feel the penetration if that makes sense?

 

[super noob]

im on your side, for a given amperage (within hobby welder capabilities) the stick will penetrate deeper than the mig, giving a stronger weld.

also the stick welder will happily weld in horrible conditions, the mig will just give porosity with no gas shielding.

i have never been able to break any of the practice welds i have stick welded, but have broken quite a few of the mig welds i have done as tests (to make sure i had set hot enough, obviously didnt for the ones that broke)

it is harder to stick weld IMO as you have to deal with rod angle, arc length that is constantly trying to change, travel speed, keeping the slag pushed back etc, mig is more point and squirt, if the settings are right then its not hard to lay a decent bead (obviously harder to get a properly good bead) that will hold.

what you should do is get some 10mm steel, set it up in a fillet and put a 3.2 rod in your stick set, 120ish amps and weld the fillet, then tell him to set his machine for full penetration on 3mm (will be not far off the same amps as your stick set) and then tell him to leave the settings alone and weld the 10mm fillet up with a stringer, then batter them both and see which one breaks...i can guess which one will hold better (i happen to know that a bit of 10mm welded with a 3.2 6013 will take 22 ton...Richard on here did the test for me before i welded up a frame for a small press, http://www.mig-welding.co.uk/forum/threads/multi-pass-mig-welds.57847/ this post goes into quite a bit of detail regarding this very arguement...)

He did offer to do a plate test using his mig, this is a part in tension so I want it to take at least 30t or enough to take the parent metal past its modulus of elasticity. He still reckons that it'll hold better with a mig set up how he wants haha

I need to do some uni work over the holidays with some suspension components so I may throw this one into the mix and see how much it should take based on calculations then test it in the machine when I'm back on site

I ran the stringers at 125A then the caps over the top at 120, angle of the picture doesn't show the height but I'm about 12mm up the plate to the edge of the fillet

They glow pretty well at those amperages...forgot to change settings once and lit a 2.5 up at 4mm amperage....only did that once...

Reminds me...need to order another MMA torch/stinger

Yeah I was welding with 1/8th 7018s on a bumper then changed to use 1/16th 6013s just to finish up a joint on a fuel tank I was making (ran out of argon for the tig) forgot to change back to 30A from 125.....that rod lasted all of three seconds


This is the piece in question anyway, before final clean up

 

[Woody.v8]

Far to wide a weave SN, Smaller multi runs would be more the norm.

 

[super noob]

Yeah I was seeing what was possible width wise as I thought I'd already laid down enough passes to make it strong!

Other side is the same overall width but made up of two separate weaves overlapping in the middle

 

[Chris Stevens]

MMA is far more difficult than MIG, particularly so if you are using hobby type equipment. However moving away from hobby gear for both processes, its far easier for someone to get good results with MIG than MMA, which means its invariably chosen for the majority of production work involving welding.

 

[Tinbasherdan]

Mig is point and squirt welding, mma takes skill and stop quoting rod sizes in imperial, you're not a bloody yank!

 

[Woody.v8]

Mig is point and squirt welding, mma takes skill and stop quoting rod sizes in imperial, you're not a bloody yank!

I still quiet often quote rod sizes in wire gauge as that,s how my old man describes them, as in "pass me a dozen 8's".
I sometimes forget when I'm at the welding supply's and do the same, To the response of a blank expression " oh i mean 4mm"

 

[super noob]

Mig is point and squirt welding, mma takes skill and stop quoting rod sizes in imperial, you're not a bloody yank!

I work in imperial all my vehicles are old!

 

[BrokenBiker]

It is worth mentioning though that mma is only 'better' than mig for your average joe wanting to weld real heavy stuff with hobby gear like me, I want to weld up 10-13mm flat bar and with mig would need 250+amps. When you move up the scale to 3 phase industrial gear and look at flux core dual shield wire there isn't much that will beat that for speed, deposition and penetration

 

[super noob]

I've not used dual shield wire before but the uni has a 400A Butters mig and that thing will eat into 1/2" plate with ease

 

[Tinbasherdan]

It is worth mentioning though that mma is only 'better' than mig for your average joe wanting to weld real heavy stuff with hobby gear like me, I want to weld up 10-13mm flat bar and with mig would need 250+amps. When you move up the scale to 3 phase industrial gear and look at flux core dual shield wire there isn't much that will beat that for speed, deposition and penetration

Even into the realms of high amp, Dual shield gear, I prefer a stick

 

[premmington]

Unless you have loads to do! MMA is the way forward!


Oh... I liked the comment, about rods sizes and not being a yank!

Yes... 2.5mm 3.2mm 4.0mm 5.0mm is a lot better!

 

[BrokenBiker]

Even into the realms of high amp, Dual shield gear, I prefer a stick

i prefer stick to anything, but im also better at stick than mig, although once i get a decent mig i think i may use the mig more as once its set up its just point and pull, but the stick set will always get used for anything heavy or if im outside etc

 

[Tinbasherdan]

i prefer stick to anything, but im also better at stick than mig, although once i get a decent mig i think i may use the mig more as once its set up its just point and pull, but the stick set will always get used for anything heavy or if im outside etc

I've done both a fair bit, but I always used to get a rollicking for burning rods when the mig set was sat next to me