MIG vs. Flux Core Welding

[Transit]

Yes, yes. I know all about the ins and outs of wire feed welding. With 110volts your not going to weld other than short arc. Most of the El Cheepo 110 v units are not more than stick welders with long rods, totally striped down, no capacitors and minimum inductance, the gun hot all the time.

And you missed SHIELDED FLUX CORE as opposed to Shelf Shielded Flux Core.

 

[cdaigle430]

I have had my little Lincoln 110V wire welder for over ten years now.
I use it on everything, just not that skilled at small stuff, does not seem to be a big need to weld thin steel on my little farm. I have only used Flux Core and never tried MIG. I want to build a big smoker and want the welds to look really good. Does MIG make better welds than Flux Core?

Thanks,
Charlie

Does your MIG have the capability to do both like mine?

120 Amp Flux Wire Welder with Wheels

Granted this one is a low duty cycle welder but it gets the job done, I paid $129 for mine on sale.

 

[Transit]

Read the specs carefully, 120 amp welder. 18 v @ 130 amps, 15% or 1-1/2 min weld time @ 115 Amps.
At 130 A the weld time is around 1 min. or 10%.
The problem with these units is people think they can do the equivalent work of a pro model. You should hear some of the projects they want to do with such a welder, like build a trailer to run on the highway. These units don't have the penetration of a pro model and that is what gives Mig a bad name.

 

[cdaigle430]

Read the specs carefully, 120 amp welder. 18 v @ 130 amps, 15% or 1-1/2 min weld time @ 115 Amps.
At 130 A the weld time is around 1 min. or 10%.
The problem with these units is people think they can do the equivalent work of a pro model. You should hear some of the projects they want to do with such a welder, like build a trailer to run on the highway. These units don't have the penetration of a pro model and that is what gives Mig a bad name.

Yep,
I know it has a low duty cycle but for the amount of time I use it, it's perfect. I am a professional welder turned Information Technology so I understand how the needs verus cost goes. I have $12,000 dollar computer system at home because I need it The welding is just a hobby/home repair item for me now.

I can't justify having my house wired for 3 phase electricity and spending $1,500 dollars plus on a machine I use maybe once a year to gain another 60% on the duty cycle. I don't see how this gives MIG a bad name?

 

[Transit]

Ok, so you know a lot more than you are letting on. Mig gets a bad rap because of the little cheepo pee shooters.
There have been many used pro-Migs for sale on Crags list and such. Have you ever been to WeldingWeb™ - Welding forum for pros and enthusiasts - Powered by vBulletin

 

[lostcause]

Read the specs carefully, 120 amp welder. 18 v @ 130 amps, 15% or 1-1/2 min weld time @ 115 Amps.
At 130 A the weld time is around 1 min. or 10%.
The problem with these units is people think they can do the equivalent work of a pro model. You should hear some of the projects they want to do with such a welder, like build a trailer to run on the highway. These units don't have the penetration of a pro model and that is what gives Mig a bad name.

i know a bunch of you have big issues with these 120v welders, especially for making trailers that travel on public roads. to be honest, i can't see what the deal is. trailers that can be hauled behind light duty trucks have very little steel on them thicker than 1/4". my trailer that i made 10+ years ago (16' deck with 5' +/- v-nose) uses c5x6.7 for the two rails and the rest of the tongue. the cross members are c3x4.1. the shackles are about 1/4", the coupler is about 3/16".

the only parts here that are thicker than 1/4" are the heels of the channel flanges. they are probably 5/16"-3/8" at the very edge of the heel and taper to 3/16"-1/4" at the toe of the flange. i have no issues with welding these shapes with a 120v welder. in fact, there are a lot of 120v welders out there now claiming to put out 140a through some intricacies and voodoo of inverter technology. my old welder is a century 90/110 wire feed that (i believe) is putting out a 90a max because i use it on the 20a input setting - i assume the 110a is only attainable on the 25a input. i've welded plenty of steel in this range with that old century, and i'd have to think that a newer lincoln or miller (or other) 140a would make it even easier.

do i get full penetration with this? absolutely not. do i care? absolutely not. i don't believe you will find any full penetration welds on any commercially built trailer anyways. you certainly need to get enough heat to obtain proper penetration to get fusion between the metals, but thinking you need full penetration everywhere is a pie dream.

in fact, to get full penetration on a channel shape, you would need to cut out a portion of the web and grind back the underside of the flange to allow an access for either a backing bar or a backgouge/backing fillet. i can't say i've seen a trailer built this way, though it's possible they exist. generally, if concerned, just weld both sides of the web & flanges and you're going to see the strength you need. the channel section will yeild before the weld as long as you get enough heat into it.

sorry for getting away from the question about a smoker, but i wanted to address this.

 

[Luremaker]

... in fact, there are a lot of 120v welders out there now claiming to put out 140a through some intricacies and voodoo of inverter technology. my old welder is a century 90/110 wire feed that (i believe) is putting out a 90a max because i use it on the 20a input setting - i assume the 110a is only attainable on the 25a input. i've welded plenty of steel in this range with that old century, and i'd have to think that a newer lincoln or miller (or other) 140a would make it even easier....

I don't want to hijack this thread but speaking of Lincoln. Anyone have any experience with the Lincoln 140 Mig. I see it is on sale for $499 CAD at Canadian Tire this week.

 

[yomax4]

If a 115v unit is on your wish list, I would go with the Lincoln. When the 115v craze hit in the early 90's I sold thousands of Lincoln SP machines in 115v. We never did have a warranty claim on one. I don't like Lincoln as a company or business model but you have to admire their 115v program. I have owned many dozen welders from Miller, Hobart, Century, Powcon, Esab, Thermal Arc and a couple of unknown origin but the small mig market is considered a throw away market and Lincoln seems to get thrown away less than than most from what I see in my travels..

 

[Transit]

Lost, consider yourself lucky, less than full penetration means a less than full strength weld. Consider, equipment produced 10 years ago was better made; take a look under the covers at the same model today. What makes Mig a constant voltage process is the large capacitor storage bank. Most all el-cheepos dont have cap banks and those that do are inadequate.

 

[gauthier]

Well,I've never used one of them 110 volt migs,so couldn't say what they will do or won't do,,but know I wouldn't buy one.

As far as full and not full penatration,,a fillit weld is not supposed to have full penatration,,think about it,,set up a tee joint,or a lap joint,,if you had full penatration you would be burning a hole through back of joint.

A fillit weld is not a full pen weld,,now that don't mean it is not supposed to have some penatration in root of joint,,but how much?

If you are using correct amps/volts for the rod/wire you are running,and you can weld,,you will get enough penatration in root of a fillit,[if you need a stronger joint than you need to come up with something other than a fillit.],if you can't turn machine heat to where you need to or you don't know how to weld,,than you will have trouble getting enough penatration and fusion,,to make a good weld.

 

[Transit]

Hummm, I must have been doing something wrong all these years. I get full penetration all the time, it may take some prep work, fit-up, V-notch, gap, multi pass. If done properly a weld will not break in a bend test. The man that taught me to weld was a WWII ship welder. He would cut my coupons across the weld and etch them to show the fusion.
Haven not done stick in years, mostly Mig and some Tig, more flux core than gas shielding. Some of the flux core wires will look like mig work. Some are just plan nasty looking.

 

[gauthier]

I said fillit weld,,we was talking fillit welds [or I thought so],go back and reread my post.,if you bevel your plate,its generally not considered a fillit weld any more.

Most structual welds are fillit welds,[bridge,buildings,car/truck/trailer frames],,if a plate or beam has to be joined to another[butt weld] it is a vee groove of some sort,but most are just tee joints,lap joints,no bevel,not intended to be full penatration.

 

[lostcause]

Hummm, I must have been doing something wrong all these years. I get full penetration all the time, it may take some prep work, fit-up, V-notch, gap, multi pass. If done properly a weld will not break in a bend test. The man that taught me to weld was a WWII ship welder. He would cut my coupons across the weld and etch them to show the fusion.
Haven not done stick in years, mostly Mig and some Tig, more flux core than gas shielding. Some of the flux core wires will look like mig work. Some are just plan nasty looking.

if you're getting full penetration, then that's fine. thing is, the rest of the world doesn't bother to. as gauthier said, for simple fabrication, it's a fillet weld world out there. there are certain special cases where full penetration welds are called for, but otherwise they aren't used because they are costly and wasteful. there's also some cases where i am pretty sure you aren't getting full penetration unless you are cutting an access hole on the backside - where you come to a tee or corner for instance. if you are using mig or flux core, you're likely going to either be using a backing bar or a backgouge to get full penetration.

 

[RPW]

Well I finally feel the need to enter this topic First I'm not a professional welder. I have taken some classes at the local community college recently but have been dabbling with welding for about the last 15 years. My first machine was an AC stick welder I picked up while being stationed in Germany. After that I've gotten a HF 110V flux core only and since then a Lincoln ProMig 140 a Miller econotig and a bobcat 225 gen/welder. I'm not pounding my chest but have found that the right tool for the job goes along way to getting the job done more effectively. What I've found about the little HF flux core is that the problem I was having with it was not with the machine but the HF wire was the worst there is. In using better wire (i.e. lincoln brand) I've found that I like using the little box. Besides lately most my welding has been outside and that has preclueded the use of the MIG. As far as full penetration as long as I'm withing the capabilities of the welder or take additional measures for proper fit etc. I do get full penetration. That's another reason for the wide range of machines. Amperage really hasn't been an issue as even when I'm welding 1/2 plate I'm really not using more than 100amps. If I do my stick rods start glowing excessively or I'm down to welding for about 1 min and then waiting.

 

[gauthier]

You get full penatration on your fillit welds?[tee,lap joint]

 

[Chilly807]

Amperage really hasn't been an issue as even when I'm welding 1/2 plate I'm really not using more than 100amps. If I do my stick rods start glowing excessively or I'm down to welding for about 1 min and then waiting.

I'm a long shot from being an expert on stick, but I think that's why you use a larger electrode for thicker metals? Not being sarcastic, just looking for feedback.

The 3/32 rods I use call for 75-100 amps, 90 is ideal according to the maker. The 1/8 rods ask for 110 amps, etc.

The pro I get advice from told me to keep to 3/32 rods for 90% of what I'll be welding, to vee out the joints and keep adding passes until it was done on thicker stuff.

Sean

 

[gauthier]

Yes and no,,you don't weld stuff in one pass unless you are working in a fab shop doing fillit welds,[or just putting on a small fillit].

You can weld 1 inch stuff with a 1/8 rod and get 100 percent fusion and penatration[talking a vee type groove].

Would you want to weld 1 inch thick stuff all the way with 1/8,no cause you want to get it done sometime,point being you are only welding a small area at a time with multi pass welds,if you know how to do it,you can do it.True with bigger rod you can run fewer passes,less starts and stop,higher heat,so there are quality reasons as well as time concerns for using a bigger filler on thicker stuff,but,you can make a quality weld with a smaller rod/wire as well,if you know how.

bigger the rod or wire the more amps it takes to burn it correctly,smaller rod or wire requires less amps to weld correctly with it..so when you change wire or rod size,you got to turn your machine up or down accordingly.

This one pass stuff was invented by welding machine salesmen for non welders to relate how many amps there machine would run,,and knowing that they didn't know how to make proper multipass welds.

 

[CharlieTR]

I don't want to hijack this thread but speaking of Lincoln. Anyone have any experience with the Lincoln 140 Mig. I see it is on sale for $499 CAD at Canadian Tire this week.

Luremaker,

That is a great machine and if the price is right I would get it.
I have almost the same machine and its nearly 10 year old.
I have built trailers for the farm, a crane, and welded 3/4 inch plates for hitchs, just need to make more passes. Never had a problem and use it all the time! Hope you get it, you won't regret it.:thumbsup:

 

[RPW]

Yep, larger rod for larger sized metal. But sometimes you have to use what you got. Pretty much my point is that for now..... I'm not welding anything thicker than 1/2 plate so pretty much all I have on hand are 5/32 or smaller.

 

[gauthier]

Now a days a 5/32 is a pretty big rod! You won't generally find them using any bigger on powerplant type work even on pipe that is about an inch thick.

Pipeline will often go up to 3/16,but thats about it,not because of thickness really,its generally all sch 40 on gas lines,just the way its welded,down,no stringer beads[cept the root is called a stringer],all one over the other