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Air Randy
04-15-2010, 12:29 AM
I got a Miller 180 for my birthday, so this will be my first foray into mig welding. I understands the basics that you need solid core wire + shielding gas or flux core wire without gas. Question is, how big of a difference does it make from one method to the other for welding basic mild steel up to 3/8 of an inch? That scenario would probably cover 90% of what I weld. I understand you get a much better weld on stainless steel, aluminum, etc when using gas. But for my scenario, are the benefits of using gas worth the cost of buying/renting a cylinder, periodic refills, etc?

teamextreme
04-15-2010, 01:08 AM
Biggest difference is the extra weld spatter when using flux core wire & no gas. With gas you get a much cleaner weld. Is it worth the extra $? That's a personal call, but I definitely prefer the gas. In fact I just re-filled my bottle for the first time yesterday. If you decide to go with gas, I found the best deal at Buckeye Welding in Commerce City. You're going to love the 180. I got a Hobart 180 last year and love it. I'm amazed how much I use it.

Groucho
04-15-2010, 07:48 AM
IMHO, I would use the solid wire and the gas.

If you plan on welding 3/8" mild steel, you will have the best chance to get close to the penetration you need for good welds with that Miller 180. I would personally stay away from welding that thick with that 180 simply because you won't get the penetration you need to make a weld that will hold up under severe stresses. It just doesn't have the poop. Thinner stuff, its a great little machine.

Flux core is usually .045, and you will have a hard time getting the power you need to weld that big stuff with the 180 and flux core. Plus, using the flux core on thinner material will require some practice as the likelihood of burning through is higher due to flux core running hotter than the solid+gas.

We use thermalarc 251's with .035 and a 85/15 steelmix on all of our 3/16" and up mild steel work. Even those will, on rare occasion, have a tough time welding the thicker stuff (1") with the penetration the job requires.

Beater
04-15-2010, 08:38 AM
gonna differ slightly with nathaniel on this. Flux core does penetrate and burn hotter than equal amperage/wire thickness shielded. for structural stuff like impact resistant bumpers and sliders you're going to be doing multi-pass anyway on thicknesses above .25

hell a 110v with flux in .035 will burn .25 thick all day long. There is a reason cored is used a lot in construction.

With good prep and a spray of "weld kleen" splatter won't be an issue.

weld with core for a while, as it will teach you some valuable lessons such as puddle/heat control and travel speed. Welding with cored wire, you will be adjusting power, not wire speed so much as you do with shielded wire. This will teach you torch control.

my .02

RockRunner
04-15-2010, 09:00 AM
Randy,
I have essentially the same machine you do but have to set the power. I am not a GOOD welder, I get by and have to grind some.

With the flux core I got more spatter and smoke, had to grind a lot even using the anti spatter spray (highly recommend that stuff)

With the solid wire and gas, Argo/C02 mix in my case, I get a cleaner weld and less splatter. Most important to me is the less smoke, I can see better. It seems too, at least in my case, that I can weld one temp lower now and get good penetration.

You are more that welcome to come over and try mine this weekend so you can see the difference between the two. I will be welding a ton.

PS Don't forget to change the internal wires, flux core has one setting and solid the other..............DAMHIK:o But I am getting better, working on some sheet metal now, that takes some learning :eek:

Air Randy
04-15-2010, 09:20 AM
IMHO, I would use the solid wire and the gas.

If you plan on welding 3/8" mild steel, you will have the best chance to get close to the penetration you need for good welds with that Miller 180. I would personally stay away from welding that thick with that 180 simply because you won't get the penetration you need to make a weld that will hold up under severe stresses. It just doesn't have the poop. Thinner stuff, its a great little machine.

Flux core is usually .045, and you will have a hard time getting the power you need to weld that big stuff with the 180 and flux core. Plus, using the flux core on thinner material will require some practice as the likelihood of burning through is higher due to flux core running hotter than the solid+gas.

We use thermalarc 251's with .035 and a 85/15 steelmix on all of our 3/16" and up mild steel work. Even those will, on rare occasion, have a tough time welding the thicker stuff (1") with the penetration the job requires.

According to the specs on the machine it will weld 5/16 in a single pass and heavier stuff with multiple passes and proper prep. I rarely ever welded anything heavier than that with my stick welder. When you get into stuff that big it's usually structural or heavy load stuff that I'll get a pro to weld for me. The machine comes setup for gas but they also include a roll of .030 flux core, so I may get to try both. Thanks for the feedback.

rover67
04-15-2010, 09:22 AM
Well everybody else stated the technical aspects. I personally just don't like welding with the flux core stuff. It's too messy and I spend too much time cleaning up spatter. I have it around for when I run out of gas and that's about it.

Blackdiamond72
04-15-2010, 09:38 AM
Maybe someone who knows better than me can chime in. I keep a bottle of pure CO2 for welding thicker steel because it runs hotter than with 75/25 argon mix. Also for when I'm tig'ing.

I do use flux cored when I'm low on gas but I made sure to get a good leather jacket and good gloves for the splatter. The best move I made when learning to weld was to get a self adjusting mask, (auto darkening I guess its called), made starting the puddle and following my lines SO much easier!

Groucho
04-15-2010, 10:06 AM
According to the specs on the machine it will weld 5/16 in a single pass and heavier stuff with multiple passes and proper prep. I rarely ever welded anything heavier than that with my stick welder. When you get into stuff that big it's usually structural or heavy load stuff that I'll get a pro to weld for me. The machine comes setup for gas but they also include a roll of .030 flux core, so I may get to try both. Thanks for the feedback.

There's the rub. The "it will weld 5/16 in a single pass and heavier stuff with multiple passes and proper prep." Just what is "proper prep" that the manufacturer used to get the machine to weld the spec material? Your guess is as good as mine. And probably as good as the Miller rep's. I have had to take classes in visual destructive and non-destructive testing for work. Believe me, I worry about welds that we do. I have seen some of the samples welders turn in for certification. Some are downright scary. Makes me glad that at least someone is checking to see that the welds people lay are going in deep enough. Every time I hire a welder, we have them present coupons for testing. We cut them apart, evaluate penetration, and weather they have the correct heat, speed, etc.

For almost every applications the 180 machine will be a great machine. I just wouldn't use it to weld a 1/2" tow point to the face of a bumper and hope that it holds when I'm being strapped out of the muck.

Congratulations on the birthday present. It will no doubt come in handy almost everywhere. Now the problem is that you will always be looking at a project with the mindset of "now how can I weld this bugger together..."

coax
04-15-2010, 10:16 AM
This is a bit off topic and I am a noob when it comes to comes to welding. Still using flux core for my small projects now and then. I think someone posted this article on mud (or maybe RS) a while back re: using gas w/ argon + brake cleaner and welding. Bad news, so wanted to share w/ folks. Imagine professionally trained welders are aware, but I sure wasn't.

Corey

Air Randy
04-15-2010, 11:23 AM
Yep, agreed. Like I said, for the critical stuff I'll go to a pro with the big machine.

"Proper prep" in my book is grinding v notches or angles when welding thicker stuff so you can get to the bottom and weld it up with multiple passes.

I had an arc welder before so I was already used to looking for projects to fabricate. :D I also picked up a used plasma cutter, which is totally new to me. So now I'm looking for stuff to practice cutting up :hill:

Beater
04-15-2010, 11:27 AM
For almost every applications the 180 machine will be a great machine. I just wouldn't use it to weld a 1/2" tow point to the face of a bumper and hope that it holds when I'm being strapped out of the muck.

Congratulations on the birthday present. It will no doubt come in handy almost everywhere. Now the problem is that you will always be looking at a project with the mindset of "now how can I weld this bugger together..."


Nathaniels point is valid. I have put 30k tow points on bumpers with a 175 amp mig machine. AFTER prepping the crap out of it, pre-heating, v'grinds, and 3 passes. Single pass "look's pretty weld" ? no.

co2 does increase penetration, but does also increase splatter and such.

Bottom line, if you are welding something that your life depends on, "I" would use either a different process (stick or high amp tig) or at least do flux core with multi pass techniques.

All those pipe rigs that you see running around with 250 amp stick machines aren't welding 1/2" pipe just with the 80amp difference. It's root plus surface/stitch passes. Remember, stick welding is essentially stationary flux core.

Groucho
04-15-2010, 11:41 AM
Certainly makes me feel better when someone does a good job of evaluating their welding. I think you're dead on with your scope of what you will be using it for.

Root passes? Treeroot? :D

I have become a nervous nelly when it comes to welding. Doesn't help much. I just want to be assured to the max extent possible that whatever we put out of the shop will not break when used for what its intended for. Whether it's on the Dodge truck bumper that the guy down the block is going to use to rip the root of a 100 year old redwood tree out of the ground, or a blackhawk helicopter flying recon. I want to give them all the chance that our welds will hold up.

Air Randy
04-15-2010, 12:06 PM
Hmm, I'm beginning to question the wisdom of selling my stick welder, just in case I need to weld something thicker than my mig unit can handle.

Hey Nakman, can I do indian giver and hang on to the arc welder? If that breaks your heart I'll let it go but if you can live without it I think I'll hang on to it.

Rezarf
04-15-2010, 01:15 PM
Well everybody else stated the technical aspects. I personally just don't like welding with the flux core stuff. It's too messy and I spend too much time cleaning up spatter. I have it around for when I run out of gas and that's about it.

X2... it is just messier and mo' dirty.

Maybe someone who knows better than me can chime in. I keep a bottle of pure CO2 for welding thicker steel because it runs hotter than with 75/25 argon mix. Also for when I'm tig'ing.

I run straight C02 and will until I start the body work on my truck, then I will invest in the argon stuff.

I do use flux cored when I'm low on gas but I made sure to get a good leather jacket and good gloves for the splatter. The best move I made when learning to weld was to get a self adjusting mask, (auto darkening I guess its called), made starting the puddle and following my lines SO much easier!

Good advice here.



I have become a nervous nelly when it comes to welding. Doesn't help much. I just want to be assured to the max extent possible that whatever we put out of the shop will not break when used for what its intended for. Whether it's on the Dodge truck bumper that the guy down the block is going to use to rip the root of a 100 year old redwood tree out of the ground, or a blackhawk helicopter flying recon. I want to give them all the chance that our welds will hold up.

Nathaniel, I am glad you think this way. It is the reason I can put so much trust into your products verses, bubba's fab shop down the road.

:thumb:

Air Randy
04-15-2010, 01:56 PM
Help me with this comment "I do use flux cored when I'm low on gas but I made sure to get a good leather jacket and good gloves for the splatter. The best move I made when learning to weld was to get a self adjusting mask, (auto darkening I guess its called), made starting the puddle and following my lines SO much easier!"

Is mig welding w/o gas significantly smokier with more sparks and splatter than arc welding with a 6130 rod? I'm finding that hard to believe.

TIMZTOY
04-15-2010, 03:25 PM
ive got the miller 180 with autoset also.. love it.. and i would never ever dream of using flux in it.. ive used that crap in the past and have it at work and i think its just horable it might be the welders were using but the flux dosent seem to penetrate.. expectually if your trying to have a pretty weld.. and dosent the wire cost more ? i bought the large tank and ive gone though like 2 spoools of wire and still have alot of gas.. i think.. its been awhile since ive used my welder.. :confused::rolleyes: at ,liest i can stare at it in my liveing room every day and wish i was builid a project. :(:(:( like my trailer or sas kit

nakman
04-15-2010, 03:30 PM
Hmm, I'm beginning to question the wisdom of selling my stick welder, just in case I need to weld something thicker than my mig unit can handle.

Hey Nakman, can I do indian giver and hang on to the arc welder? If that breaks your heart I'll let it go but if you can live without it I think I'll hang on to it.

Yeah, you need it more than me.. you suck tho :D

DaveInDenver
04-15-2010, 03:47 PM
Yeah, you need it more than me.. you suck tho :D
I'm sensing that there should be a restocking fee evaluated in barley pop.

Beater
04-15-2010, 04:40 PM
Help me with this comment "I do use flux cored when I'm low on gas but I made sure to get a good leather jacket and good gloves for the splatter. The best move I made when learning to weld was to get a self adjusting mask, (auto darkening I guess its called), made starting the puddle and following my lines SO much easier!"

Is mig welding w/o gas significantly smokier with more sparks and splatter than arc welding with a 6130 rod? I'm finding that hard to believe.

nuttin is worse than 6130, except maybe hardfacing... They both produce heavy particilate smoke. You have better puddle visibility on flux core wire-feed than you do stick. At least I think so.

Air Randy
04-15-2010, 06:18 PM
OK, thats what I thought, so even if I go gasless for a while I won't be suffering any worse than I was arc welding.

Air Randy
04-15-2010, 06:20 PM
I'm sensing that there should be a restocking fee evaluated in barley pop.

I AGREE FULLY! Nakman, tell me your brand and a case of it :beer::beer::beer: will be provided at CM, plus anytime you need welding you just come on by. :thumb:

Thanks :bowdown:

RicardoJM
04-15-2010, 08:06 PM
So, if I"m following this thread correctly; Nakman's new welder is not heading north from my garage but it heading south to become Randy's old welder...

Air Randy
04-15-2010, 08:07 PM
So, if I"m following this thread correctly; Nakman's new welder is not heading north from my garage but it heading south to become Randy's old welder...

Yes:o:o:o

Beater
04-15-2010, 08:46 PM
sorry tim....

Corbet
04-15-2010, 09:58 PM
I have not tried it yet but can I hook up my powertank to run CO2? Special regulator required? I've been running the standard 25/75 mix with my Miller 211 so far.

Randy, what's stopping you from getting a bottle right away?

Air Randy
04-15-2010, 10:04 PM
I have not tried it yet but can I hook up my powertank to run CO2? Special regulator required? I've been running the standard 25/75 mix with my Miller 211 so far.

Randy, what's stopping you from getting a bottle right away?

Nothing, I just wanted to make sure it was really worth it. I'm so used to arc welding with stick I thought welding with flux core wire might be about the same.

Corbet
04-15-2010, 10:36 PM
got it:thumb: makes sense. Once you get a bottle I bet you never go without though.

Air Randy
04-16-2010, 08:30 AM
You're probably right. Another question: I got the plasma cutter hooked up and functioning last night. I know when I've used oxy/acet torches in the past to cut you angle the torch slightly into the direction of cut and "push" the puddle forward. Do you do it the same way with the plasma, or do you "drag" the puddle or maybe it doesn't make any difference?

Beater
04-16-2010, 08:40 AM
I have a love hate relationship with my plasma cutter. Unless you leave your plasma hooked up all the time, I find it easier to just whip out the oxy/fuel and be done with it. That aside, it depends on amperage/thickness.

On thick stuff, I undercut slightly. On thin, I stay vertical. I always use a drag or pull motion with my arm, never pushing. I find that you get less variations. You can usually drag your tip at less than 30a anyway. you should have little to NO puddle with plasma. If your building a puddle on plasma, your moving too slow or not using the right amperage for that thickness

Big tip: If you have the option, get the "art metal" or "fine" tip, whatever the mfg calls yours. the small kerf makes ALL the difference imho.

Air Randy
04-16-2010, 04:40 PM
I used it today to cut the brake backing plate off of a mini truck axle. Thats fairly thick material and it cut through it like it was a paper. I used the same technique I used with the oxy torch and it worked fine. Thanks for the tips.

nakman
04-16-2010, 05:02 PM
I AGREE FULLY! Nakman, tell me your brand and a case of it :beer::beer::beer: will be provided at CM, plus anytime you need welding you just come on by. :thumb:

Thanks :bowdown:

Randy as long as it's cold I'm happy man.. it's all good looking forward to sharing a few out at BFE again. :beer: :drink: :beer2:

Air Randy
04-16-2010, 05:15 PM
Randy as long as it's cold I'm happy man.. it's all good looking forward to sharing a few out at BFE again. :beer: :drink: :beer2:

Me too, consider it done!