[Skiddz]

Quick background. All of my arc welding experience has been in a classroom, 3x/week since January 24. SMAW, GMAW and for the past 2 weeks, FCAW (Dual Shield) Flat and Fillet I've got figured out with all 3 types and SMAW vertical uphill is decent.

Currently working on 3G pieces in preparation for a cert test in about this time next week. 6" x 2" x 1/2" plate, 1" x 8" X 3/8" backer, 1/4" gap, 30 degree angle on the work pieces. (60 degree opening) Wire is 0.45"

First 4 to 4 1/2" inches of the root pass are ok, but the last bit goes haywire. Arc seems to sputter and the resulting bead (if you can call this portion a "bead") turns very ropy and piles up. Literally everyone in the class is seeing this and it's almost become a running joke after 5 sessions of vert uphill. The machine I'm working on seems work best for me at 22.7 volts and not quite 300 IPM wire speed. Gas (CO2) is running about 30CFH. Other students are running similar settings.

We've all started watching each other run to see if an extra pair of eyes can see what might be going on, but there's nothing glaringly obvious going on with technique (Not surprising since we're all newbies still) and with 10 of us having similar issues on 5 different machines, it's getting very frustrating.

On the rare occasion one of us gets a decent root pass in, the following stringers seem to flow ok, but the top of the bead tends to get more buildup than the lower 4 - 4 1/2" inches and by the time we've got 5 to 6 passes in the groove and are ready for cover passes, that area is already right at the excess reinforcement limit.

Towards the end of class tonight, I was able to complete all my passes, but I had to grind down the last 3 stringers in the "bummer zone" low enough so I could get my cover passes done without them being too tall. Cover passes went down fine after that.

Anyone have any idea what's causing all the grief in that last inch and a half or what to look for in the puddle? Again, we're all pretty decent with the first 2/3 of the passes but that last bit just doesn't seem to want to play nice.

Thx!

[Poland308]

Can you stop to let it cool before it goes haywire? Then just restart?

[Skiddz]

Can you stop to let it cool before it goes haywire? Then just restart?

I tried that on one of the 1st couple sessions doing this and after cutting and bending, saw I didn't get complete penetration at the root in the restart area. Definitely a technique and experience issue with that, but don't know if there's time to get that nailed down before the test. We only have 6 more sessions and we start testing in 3 days.

That everyone is having problems with things building up too high in the upper portions of the pass is telling. Something we're all doing is causing it, but we're all at a loss to identify what it is.

[Poland308]

Before you restart you need to grind back into the last weld. It’s called feathering. Jody mentions it in some videos. It’s common practice with stick welding too.

[PeteM]

Sounds like either reaching with the electrode (where you drop your wrist angle as you go up instead of raising your wrist), or drifting back out of the good CTWD.

[Skiddz]

Sounds like either reaching with the electrode (where you drop your wrist angle as you go up instead of raising your wrist), or drifting back out of the good CTWD.

Instructors said the same thing, but we've been watching each other to see if that's the case. It doesn't appear to be. 2 classes ago, another student and I watched every pass the other made and we both ended up scratching our heads because it appears neither of those issues is the case. I thought 6010 vertical uphill was frustrating.

[Skiddz]

Well, last night was an exercise in frustration. Over the weekend I'd made parts for my test plates so I didn't "waste" time grinding in class. Got them tacked up and then grabbed some scrap from last week and ran some practice passes. WTH? The dinosaur backbones are back...

CO2 bottle was getting pretty low so figured it was a gas issue. Got the bottle swapped out, purged the line and tried again. Great. I've forgotten how to weld over the weekend...

Finally got back in sync and made a few 3F passes and then tacked a test piece to my fixture. Deep breath and started my root pass.. First 4-1/2 inches were nice then it went to crap again... Ground all the nasty parts out back to the backing plate and tried again. Bead stacked up tall again. Ground that out and went back to 2F for a bit. Those passes came out nice and flat.

Was ready to try again and was told the machine was out of wire and there were no more spools on hand... Maybe that was a good thing.

Hoping the bad ju-ju is gone tonight...

[Skiddz]

Bad ju-ju remains. Struggled with the machine most of the night. Had the instructor sit with it for quite some time to try and get it figured out. Settings that were working fine previously weren't cutting it with the new wire (Same stuff, I looked at the labels on the spools)

I finally jumped to another machine and got a test piece finished, but still had to grind the upper portion of the root pass back..

Instructor finally got the machine figured out with settings quite different than what had been running good for the past couple weeks. No idea what changed, but my son was finally able to start putting down good passes with it. He's got one more cover pass to knock out and he's ready for cutting and bending.

Going to cut and bend test my finished piece tonight, but have 2 more test pieces tacked up just in case that piece fails. Fingers crossed.

[Skiddz]

Well, I passed! Thought for sure I'd have a couple defects once the coupon was cut apart, but nope. Good penetration into the base metal, no voids/crack/holes to be seen. Bend test went just fine with no issues whatsoever. Relieved to have that done and over with.

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Being a glutton for punishment, I'm going to make up some parts and try to get this done with stick next week.

[tungstendipper]

Good Job!

[Skiddz]

Good Job!

Thanks. I was worried it would be Swiss cheese as I was cutting it apart. I relaxed quite a bit once I got everything cleaned up and couldn't see any issues.

Once the first piece bent ok, I was pretty confident the other one would be ok.



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[LtBadd]

Congrats, nice looking coupons!

[Skiddz]

Congrats, nice looking coupons!

Thx. I'm going to try to make magnets out of them.

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