mig and flux core tips and techniques, equipment, filler metal
Ryclark68
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    Texas

Howdy guys and gals,
Brand new member/welder here, ran my first weld 7 days ago! This is a long post. Sort of an introduction, asking for advice, and doing my best to provide a post that may help other week 1 welders like myself out there.

As I near earning my Bachelors of Science in Health in May, I plan on completely changing career paths. While in school I learned my true passion was working with my hands, power tools, and being outside in the elements. It's simply my happy place!


Enough about me, I figured I'd show off my HORRIBLE first welds for a good laugh, and show you guys my progress so far.
I'm going to post up a few things that I'd like a few opinions on. I know many of these are OPINIONS only, there's more than one way to skin a cat.

Using GMAW process with my new lincoln 210 mp!

1. Opinions on surface prep for MIG processes *for practice*? (Obviously the cleaner the better....)
Here's a pic of my workpiece today before prep
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Here's after light sanding with an angle grinder, leaving a thin layer of mill scale, yet very smooth and clean
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Finally....Ground all the mill scale off, which took significantly longer than the previous pic!
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Question: In what circumstances would these three 'surface preps' be acceptable? Again, the cleaner the better. I'm curious if, and when it would ever be acceptable to lay down some mig on any surface without any prep at all... Then what circumstances call for "light" prep like in the second picture. Finally, when will you REALLY need to get all that mill scale off?


-Comedy relief, here's my first pad of beads with .025 wire, running something like 40-50 cfm of c25 gas (oops), on some random settings!!
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On to the progress! Here's today!
GMAW Process
C25 Gas @ 15-20 cfm
1/8" mild steel
.030 ER70S-6 wire
Lincoln powermig 210 mp set to 280ipm, 19 V

Single beads (First bead on top left had hood WAY too dark)
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Went way better than expected!... Second pass (Top right was first bead, still too dark, couldn't see neighboring bead)
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In this pic, the bottom left bead with the slight porosity on the right hand side was due to a HUGE gust of wind outside. I paused and tried to angle my shielding gas to protect the weld pool, didn't turn out too good! Would love some tips on working around wind gusts

Those went pretty well, so I went crazy and set up a T-Joint!
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Obviously need some pointers on getting that bead looking nice and seamless, instead of 5 separate beads.

Looking forward to my future endeavors, and thankful to be a part of this community.
Very excited for whats to come, and thank you in advance for any constructive criticism.

------------------------------
RYAN CLARK
PLANO TX
-FOR HIRE!
Acta non Verba
-Actions, not Words
cj737
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    Thu Sep 29, 2016 8:59 am

For hard wire MIG, you want ALL the scale removed. You don't need to clean the entire sheet, but at least a 1" strip adjacent to your weld, front and back side (depending upon thickness). You can run self-shielded Flux Core on your box, and that's a very good choice of wire. You swap the leads around so your Gun is plugged into the - Port, not + like MIG. you don't need gas with Flux Core, it has a slag like stick rods to shield it. It can be run without removing mill scale, but removing is best still.

On your padded beads, many appear to be "cold". That's indicated by a lack of fusion on the edges. Your fillet welds on the T at the bottom picture look about perfectly burned in.

Typically, I run about 25CFH for MIG gas, 40 is probably too high. When welding, you're looking for the sound to be a sizzle or paper tearing sound. Sparks and spatter are an indication of too hot or too cold settings. Watch the "toes" of the weld to tell you which it is. You can "push" or "pull" MIG, so practice both directions/techniques for best skill building. And examine the backside of your practice pieces. You want a good heat mark to prove you've gotten good penetration. Cut and etch are the best proofs though-

Another great practice routine is to tack a piece of 3/16-1/4" sheet. Scribe 1" square grid. Place a good hot tack in the intersection. Get used to putting that tack down consistently. Once you've done that, you can then split the distances, adding supplemental tacks. Ultimately, you connect all the dots by splitting the distances. Tacking with MIG is a really valuable skill because you will find projects where thin sheet is used, and tacking is about all you can get away with. So don't underestimate that practice.
tweake
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    Mon Dec 18, 2017 4:53 am
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i'm another newbie.

one simple thing i have been doing is to put the joints into the vice and break them.
you can where it didn't fuse very well.

you want to clean all the mill scale off and don't forget your ground point. it helps to have a good ground going through shiny metal. it makes things so much easier to learn when your not chasing your tail due to a poor ground connection.
tweak it until it breaks
Ryclark68
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-cj737, thanks for all the information!
I failed to read my regulator correctly - I blame my excitement to get started - and set set my flow to 20 L/min, instead of 20 CFH. LOL

I do plan on doing FCAW soon, I wanted to try my hand at GMAW and SMAW first. Just personal preference, no real reason why!

I had an opportunity today to weld at my local steel shop after chatting with one of their welders. He quickly cleaned up my sloppy gun angle which made ALL the difference in the world.
Phone died today just as I was getting started, but did manage to get a picture to show progress after my first experience with a legitimate welder.
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This was pushing, I've gotten consistent beads with good penetration and fusion with this method.

I couldn't seem to get good fusion while pulling however. Most had a cold, rounded bead look to them. When pulling, do you typically move a bit faster, slow, the same as pushing? I found when I moved a bit quicker I achieved cleaner toe lines.

I'm a bit confused on your practice routine regarding the 1" square grid. Having a hard time picturing exactly what you're instructing me to practice.

-tweake, thank you for the reply as well!
I was a former commercial sales manager at a car audio shop. I do know just a handful of things about electric circuits. My work-piece connection (NOT a "ground"...) will ALWAYS be perfectly cleaned every day before any welds occur.
Good man for pointing that out. I'm sure there are a LOT of beginners who are shooting themselves in the foot due to this error.
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cj737
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    Thu Sep 29, 2016 8:59 am

When I pull, I make small reverse Cs. When I push, I make tighter Cs, I a forward motion.

The grid is to put some distance between your tacks. The point is to have a controlled spacing. Then, split the next tack 1/2”,then 1/4”, then 1/8”, and so on. Try to make the tacks as consistent in size to each other, fused edges, but small tacks. It teaches puddle reading and heat control.
Ryclark68
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-cj737
Got it now, I appreciate the immediate feedback. Now I have new skills to practice tomorrow!
I see what you mean regarding the tack grid. I do need practice simply watching the weld pool, and adequate fusion is obviously my biggest issue at the moment.

All in good time, I will regularly post as I take progress pics of all my work...not just welds!
Acta non Verba
-Actions, not Words
cj737
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    Thu Sep 29, 2016 8:59 am

Be warned: MIG is a process that can be deceiving. Beads can look great, but penetration can be non-existent. As you learn, you'll see better looking welds but you do need to bend test pieces or cut and etch them to understand if your great looking welds actually have any strength. If you stay to fairly thin material (3/16" or thinner) then the AutoSet parameters and good looking fusion will probably yield adequate strength for the application. Just be always aware of strength issues, and of course, liability where hazardous usage/human life are involved. ;)

I always prefer to teach someone with Stick welding personally. It really is a great, flexible process that teaches the best fundamentals: rod manipulation, puddle control, penetration, positions, etc. You can learn these too with MIG, but if you know how to Stick, its easier to translate these things to TIG and MIG. Hence the tack drill. At least you'll begin to see the base metal and tack puddle fuse. Something really important to watch when you weld, especially MIG. Get your face in there tight and watch the edges closely. You'll see what you need to soon enough.

I'm sure you will do quite fine on your new adventure :) Welding is a bad-ass skill and once you get it done to a level of competence, NOTHING ever looks the same again. Make that? Sure can! How about that? Yep, can do! And that? Not a problem... These are all the little voices ringing in your head as you walk through a furniture store, or hardware store, or equipment shop. You'll see...
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