Flux Core Wire For Multi Pass

[Ford850]

I know there is a difference in wire designed for single vs multi pass welds, but I'm wondering if anyone has had real issues with this. Have you noticed a problem using 'single pass only' flux core wire when building up welds with multiple passes on your projects? Difficulties, cracks, or anything else?

 

[Rancher Ed]

My understanding is the single pass only flux core wires have extra cleaning and alloying elements in the flux. For example, Lincoln's E71T-14S (Innershield NR-152) specifically says it is "designed for high speed welding of specially coated steels", and one of the typical applications is "continuous welding on galvanized or zinc coated carbon steel". To do this well the flux must have more cleaning elements to tie up and float the coating in the slag and alloying elements to maintain the required strength in the weld metal. My expectation would be making multi-pass welds with this wire would result in a more brittle weld and an increased chance for solidification cracking (hot cracking).

I do not have any first hand experience with this, so I do not know how noticeable this is when working on a project. Is it noticable with 2 passes, or 10? I'm not really sure.

 

[bplayer405]

I'm pretty new to welding, but have had issues with flux core wire. Biggest was with single pass GS wire from HF. I could not get it to weld to itself at all. It would act like it was slick and slide away from a previous weld; leaving cracks and pinholes. Thats a real problem when trying to fill a hole or you don't have your settings just right and need to do another run. A little research and I tried E71T-11 from Hobart and those problems were fixed. NR211-MP from Lincoln works great also.

 

[sonny580]

That chimna crap wont work at all!---I use Hobart wire in my old Century and it welds good,---even outside where 99% of my welding is done.

 

[joedaddy]

When using flux-core wire it's extremely important to clean all of the flux from the weld before the next pass. I usually use a wire brush on a 4 1/2" grinder. Multi-pass welding is easy, it's just best to stack the welds in a logical pattern for the type of joint and the joint prep. The heaviest plate I've welded was 2 1/2" with a double J groove butt joint, unfortunately, I can't remember how many passes it took.

 

[Greg Lyle]

I just bought my son a flux core for his birthday. It was like 150. He loves it.

 

[PILOON]

OK, I bought a 'flux core', (an el cheapo), mainly for very thin metals as I have a 220 rod machine for HD work.
Don't know if is me, but I feel that the wire feeds much too fast.
Speed control hardly affects it, or so it seems.
What should the ft/min be like? heck I barely hit the trigger and out comes about 1 ft. or more, and is it common to sparkle like crazy?
Heck so many sparks that I'd be scared to weld indoors.
As I said cheap and only runs on 110.
Could it be the cheap ChiCom wire? should I try a well known brand?

 

[Yomax4]

You'll have your best luck with E71T-11 for gasless. the TGS is crap and none of it is created equal.

 

[California]

You'll have your best luck with E71T-11 for gasless. the TGS is crap and none of it is created equal.

T-11 flux core wire is made to a specific AWS standard. Lincoln and Hobart are common examples.

T-GS on the other hand, claims conformance only to its manufacturer's standards. Obviously quality and performance can differ.

Based on advice I found here, I tried INE's GS-spec flux wire. I concluded it is top quality. INE is a top-tier Italian company. "Designed for all position single pass and multi pass welding".

If others have found top quality flux core brands lets hear about them in this thread.