I've used self shielded flux core wire in Alaska in 90-MPH winds. Couldn't hardly walk, but could set and weld all day. Try that with gas shielded wire.:laugh: I'd guess the number one reason for gas shielded flux core wire in the high deposit rate.

 

More deposition deeper penetration.

 

Is that gas shielded flux core or self shielded flux core you're referring to?

 

Most solid wire welding can meet strength requirements but not impact strength. As more attention is now paid to earthquake codes flux core gas shielded and unshielded can meet these standards.
Long before earthquake standards were a big concern in Northern Canada they paid attention to impact strengths because it was an indication of how a structure would take loads ar sub zero temperatures. The solution was flux core processes. I have noticed as the requirement for higher impact strengths have been demanded in warm climates like California the process of choice is flux core.
If you look at the packaging you often see Charpy impact values at a certain temp... - 20 is one temp. It is interesting compare the stated values between different wires.
Flux cored wires that do not use gas are very smokey. They are not popular inside a building. Great for out in the weather :')

 

Ah, I was under the impression flux core's only advantage was that it could be used outdoors. So flux core wire also makes a stronger weld overall???

I'm *guessing* the takeaway lesson is that: If you're doing an application that uses flux core, use gas shielded where it's not windy and self shielded where it is windy?

 

The gas shielded flux core wire is also a bit cleaner.

 

I'm going to put my noob cap back on and ask a stupid question. When exactly are you supposed to use flux core wire instead of solid wire? I get that if you're outside you HAVE to use flux core just for sake of not being able to use a shielding gas, but I've routinely seen people use self shielding flux core indoors (and of course gas shielded flux core indoors). I'm not even sure how to ask this question, but save for the pure necessity of being in an outdoor environment, why/when would flux core wire be necessary? All the literature and videos I've seen do a great job of explaining the operation of flux core wire, but not WHY you would need to use it beyond the whole outdoor thing.

 

Increased penetration. Good for welding thick steel. Increased current density over solid wire, more amps per square inch.

 

@ kestrel452 - View FCAW-G as a deep fusion and heavy deposition rate welding process for multi-position work on thick materials. Yields a spray-like transfer with minimal spatter. As 'lotechman' mentioned, the process typically delivers Charpy V-Notch impact toughness tested to -40°F. Know a dude who fabricates massive bulldozers using 0.052" and 0.0625" outer shield wire. The welds are pro. Personally, have only run FCAW-G on 1/4" mild steel in 2F & 3F positions. Reminds me of a hot version of SMAW with easy:easy slag removal. FCAW-S is a cheap alternative to solid MIG and, as others have stated, gives deep fusion. Spattery, but good fusion.


From Lincoln Electric,

"Gas-shielded, flux-cored electrodes incorporate a double shielding system by using an external shielding gas as well as a slag system. The shielding gas is required to protect the arc and molten metal from the atmosphere. It also results in exceptionally smooth arc characteristics, compared to self-shielded electrodes. They use either a rutile slag system or a basic slag system. The rutile system is the most common and is characterized by a smooth arc with complete slag coverage of the weld. The basic slag system, while producing a globular metal transfer and thinner slag coverage, can be more resistant to weld cold cracking.

Most FCAW-G electrodes are ideal for all-position welding and all deliver great mechanical properties with high deposition rates. They are used effectively in general shop fabrication, structural steel (including seismic applications), shipbuilding, offshore, pipeline and other applications. FCAW electrodes can be used similarly to SMAW electrodes with a few notable benefits in the process itself. First, SMAW electrodes must be fed manually into a weld joint, making only short welds and resulting in a lot of stop and restart areas in the weld. Restart areas generally have a higher chance of containing a weld defect than any other part of the weld. With the FCAW process, the weld can be made for as long as the welder can comfortably reach before having to stop the arc and reposition themselves. This results in less restart areas in the weld, and ultimately, less chances for weld defects."

 

@ kestrel452 - View FCAW-G as a deep fusion and heavy deposition rate welding process for multi-position work on thick materials. Yields a spray-like transfer with minimal spatter. As 'lotechman' mentioned, the process typically delivers Charpy V-Notch impact toughness tested to -40°F. Know a dude who fabricates massive bulldozers using 0.052" and 0.0625" outer shield wire. The welds are pro. Personally, have only run FCAW-G on 1/4" mild steel in 2F & 3F positions. Reminds me of a hot version of SMAW with easy:easy slag removal. FCAW-S is a cheap alternative to solid MIG and, as others have stated, gives deep fusion. Spattery, but good fusion.

Thanks for the explanation ManoKai. I read that flux core wire is good for "dirty" metal because it floats the contaminants to the top. Does the same hold true for gas shielded flux core?

 

There are a lot more choices with dual shield wire as far different alloys and deposition rates .

 

@ kestrel452 - believe you are correct. Both self-shielded and gas-shielded flux core electrodes contain de-oxidizing elements (eg. titanium dioxide) within the core to trap/float impurities, resident on the base metal, to the surface via slag. Check out BLUE's take at www.millerwelds.com/resources/articles/Proper-welding-wire-selection/ . IIRC, the Cu coating on solid MIG electrodes performs the same de-ox function.

 

Gas shielded flux core wire can be used outdoors. We use it outdoors but the wind must be minimal and sometimes we have to set up a wind brake or tarp to help avoid porosity.
If the wind is too much for gas shielded flux core process, we brake out the 7018 stick.

 

Another benefit with the dual shield wire compared to inner shield is that the gas cools the gun so you can avoid buying the special, meaning expensive gun devoted for innershield .

 

Yeah, they sure are proud of those puppies aren't they! :angry:

 

I do have a question about wire selection.

Lincoln's and Hobart's product webpages seem to be devoid of information regarding SP/MP compatibility for gas shielded flux core wire. I was looking at E71T-1 FCAW-G wire since it looks to be the all-purpose type, and came across the Lincoln Outershield 71M which looks like a decent all-purpose wire. Does anyone know if this wire is multi-pass compatible?

As fas as self shielding wire is concerned, the literature seems to indicate E71T-11 as being "the" general purpose FCAW-S wire. Are there any applications I should NOT use E71T-11 wire? I'm not going to be building skyscrapers or anything, just home and farm type stuff.

 

As fas as self shielding wire is concerned, the literature seems to indicate E71T-11 as being "the" general purpose FCAW-S wire. Are there any applications I should NOT use E71T-11 wire? I'm not going to be building skyscrapers or anything, just home and farm type stuff.

Before the Northridge earthquake in California Lincoln and Hobart didn't put thickness limitations on their wire. I can't tell you how many 1-inch side bend V-butt plate tests I took with Hobart's 21-B, never failed one. In my opinion for general fab work Lincoln's NR-212 and Hobart's 21-B are hard to beat.

 

you can lay down a lot of metal very quickly with the gas shielded flux core, especially in diameters 3/32 and up. the company sent out 1/8" backing bars instead of 1/4" by mistake and i was burning through them like they were made out of tissue paper.

 

@ kestrel452 - "71M" good for all apps and positions, 'cept vertical down. Grab your turnout gear and a heat shield and run it.

 

We ran hundreds of tons each of Lincoln Outershield 71M Elite1/16 , co2shielded and Esab Coreshield8 on the World Trade Center along with Lincoln LA-75 /860 flux sub arc too. All have their place

 

on the javits center we were lucky to have innershield. the wtc re-build must have been an amazing experience from many standpoints!!

 

We welded 8 inch plate with all wires ,over head too.

 

I have no idea what Lincoln is talking about low alloy.

I don't know how true this is, I've had several welding inspectors tell me they have never seen anybody pass a bend test with NR-211. I've run tons of NR-211 but never had to test with it. NR-212 came out after I got out of welding and went into management. I've bought tons of it for jobs, but other than helping someone set their machine I never ran it on the job. I bought a roll of my own for here at home, I like it a lot better than NR-211. Like I side before for general fab work you can't beat NR-212 or 21-B.

 

Understood, sir. Thank you

Have any similar recommendations for gas shielded flux core?

 

Well here at home I don't run a lot of dual shield, but I've had good luck with ESAB's 710X.
First picture is overhead, second picture is vertical up hill with 710X.

 

Unfortunately 710X (or 710XL as Lincoln brands it) doesn't come in spools small enough go inside a Millermatic 211. I'll probably end up buying a couple spools of 71M for FCAW-G.

 

NR -211 gets brittle in multi pass work , NR 232/233 are the wires for FEMA low hydrogen structural work and repair work.

 

Not to cloud this issue too much, but I run flux core pretty much exclusively in my Lincoln SP-135P (115 volt wire feeder) even though I have a gas bottle. Welder is more portable that way, more oomph with the flux core too, and I weld exclusively outdoors.

Anyway, I run Hobart Fabshield 21B (E71T-11) as it is suitable for multiple passes where Hobart's Fabshield 23 (E71T-GS) is NOT suitable for multiple passes (do the research yourself if you do not believe me). I imagine the same holds similar for the Lincoln versions too as another mentioned how brittle it gets with multiple passes. I do not burn the Lincoln's in my case as it is harder and more expensive for me to obtain so I have not actually researched it. I also like Hobarts 2lb spools much more so than Lincoln's 1 lb spool size when buying little spools. I have run many E71T-GS before I new the difference and I never liked E71T-GS when I had to make multiple passes. Once I figured things out I definitely like E71T-11 much better for my uses.

Granted the E71T-GS is earthquake rated where the E71T-11 is not earthquake rated, but the E71T-GS getting brittle with multiple passes in not good either for a backyard welder using a 115 volt wire feed unit where you have to make multiple passes on thicker stuff due to small machine size. All I know is E71T-11 will continue to always be in my welder where I will never ever buy E71T-GS again. I have even had good luck repairing some cast irons with E71T-11. All in all I am a huge fan of Hobart Fabshield 21B (E71T-11).

 

@ ScottYoung - the "cheap" in my above post was aimed at a comparison with GMAW, not FCAW-G, in the context of financial. However, MIG and FCAW-G are closely matched in the total cost of doing business. We'll proceed.

Understand there are high-dollar flux core wires used in industry, especially with pipeliners. While there are FCAW-S electrodes that are more expensive relative to solid wires, welding with self-shielded flux core electrodes does not require a compressed gas cylinder, shielding gas, regulator, hose, etc. A thought. Welder A runs FCAW-S with the "expensive" electrode. Welder B uses FCAW-G with a wire of equal high-strength mechanical properties. Forget the environment, etc. Hourly cost of operation for Welder A is lower than Welder B.

In fact, Miller states running flux-core versus SMAW on a particular job, saved a company 30%:http://www.millerwelds.com/resource...d-welding-fcaw-high-strength-pipeline-welding-alternative-to-stick-welding-smaw. Read the final paragraph.

Apples to apples. FCAW-S is a financially cheaper alternative to FCAW-G and MIG.

 

I may be wrong, but the 211 mp is 71t-11. If memory serves me right, all 71t-11 which includes lincoln's 211mp is thickness limited and three pass limited. each pass much contain base/parent metal. The single pass version are 71t-11g & gs.

Since 71t-11 is the wire in question, nr211mp will do nicely.

 

OK, well we'll see what I got, hopefully it's not to old? I think I have some 1/2-inch thick coupons cut already.

 

@ CEP - how'd you like the ESAB 710X? Your 3G image looks money! Have only used Lincoln Ultracore to date. A good buddy of mine gifted me a 33# roll of ESAB 710X-M in 0.045. Need to fill up on C25 before testing her out on some 1/4" mild steel.

 

I really like it! Childs play to run. I've run a lot of other brands, but can't remember the names. Because that was the 1970s or early 1980s.



Well, I have 3 or 4 rolls of NR-211, but I gave my pie pans away! So I have no way to load the 14-pound coils in the LN-25!