This is probably a rookie problem, hence the rookie question, but I am one of those "self taught" stick welders, and I have a puzzling situation.

I have welded a ball (cut from a trailer hitch) to the end of a piece of 3/4" square. Seemed to go pretty good.

However, I noticed a shallow cleft area that parallels the bead up on the ball. So I figure to hit it with a shallow grind and simply fill it with another bead. Well, as that one fills, another crevice forms above the new weld. This is not a sharp crack, but more of a soft-edged fissure.

I'm using a Lincoln 225AC. I've tried both 7018's and 1611's... same problem. And I've backed down on my amperage about as low as I can go.

Any ideas (besides "you need to go to welding school" <_< I know, I know. )

Thanks,

Don

It is undercutting. What is happening is the fill is melting some of the parent metal, but not fusing. When the weld cools and shrinks it pulls itself apart.

I have done it myself, and I fixed it by working the bead wider and keeping the puddle hot longer moving the puddle down the seam slower, so more fill material was added. I do not know if this is the right way, but it worked for me and what I was doing. I was working on 1/4 inch material.

My prof kept a few of my samples because they were so clear...I still don't know how to feel about that and it has been 12 years... (not welding school, manufacturing technology lab. We had about an hour of book training and 30 minutes of hands on welding)

I did it a few weeks ago with a MIG too, running flux core. I just slowed down and it was better. I do not weld very often.

Phil

First, 7018 is DC rod, not AC. E 6011 is AC but your amperage is too high. E6011 is kind of tricky to run till you get used to it but it's less sensitive to dirt and poor conditions. It's always going to give you a rough bead compared to a 70xx rod as it's a fast freeze rod. As Phil says it's pulling the weld causing the cracks.

How deep have you scarfed the join? You're welding pretty thick sections which takes more care and is trickier. Scarf (grind 45* at the joint) to half the depth of the material or more. Make s small root pass and multiple fillet passes, none of them heavy. Be SURE to chip all the slag off before every pass.

Okay, there are plenty of experienced welders here, myself included who wouldn't need to make this kind of weld but it takes experience and practice. This is a bit overkill for what you're doing, usually needed on much heavier welds but it will work to prevent shrink checking in the weld effect zone. (parallel to the bead)

Frosty the Lucky.

Undercut is caused by pulling the electrode out of the puddel to soon ! let the rod sit a bit longer and if you are still getting it more pratice . sho some photos of your weld .

Sam

Just as Sam says. The mantra of fusion welding is, "make a puddle, fill the puddle." Torch, mig, tig, stick makes no difference, the rule holds.

Frosty the Lucky.

Just as Sam says. The mantra of fusion welding is, "make a puddle, fill the puddle." Torch, mig, tig, stick makes no difference, the rule holds.

Frosty the Lucky.

Ditto. I learned how to weld with O/A from someone who really knew how to explain what to do, and its translated seamlessly to all those types of welding. No further instruction whatsoever, it's all basically the same once you understand it. I personally find stick the most difficult to do well, but its also the one I have the least experience with, and fortunately I have little need for it anymore. If you have a set of torches, I'd recommend trying them out for welding...it's obviously less efficient than arc welding, but everything moves a little slower and it's easier to see what's going on as it's happening. Master that and you're golden for all the rest.

Thank you all for the advice.

I can see that I need a lot more practice.

If it is undercut that is caused by lack of fill, amperage can be a factor, but if you are welding in the flat or horizontal position you should be able to run hot. Like samcro said you are pulling the rod out too fast. Look at the puddle while welding, set up a test piece like a "T joint" do a fillet weld on both sides for practice. You can do multi pass welds, you can actually see undercut happening there will be a dark line along side the puddle. Learn to watch the puddle, when its full move forward, use motion a weave or whipping is good with 6011. It takes lots of practice to get real good at stick welding

I see what you mean. I suppose that welding on a convex (2" ball) surface only complicates matters.

If the other side is beveled/chamfered then the spherical surface should be OK and not a further complication. If it bugs you, get the grinder in there and make it not bug you.

Phil

The smaller the diameter- the harder it is to weld. 6 inch pipe is easy to weld compared to 3 inch pipe. When you get to 24 inch you only need plate certification to weld it. The smaller the radius, the more you have to move to keep the angle of the rod in the correct position

Clinton is right about the size of the round stock. Being a Boilermaker tube welder I can't say (pipe) LOL. The smaller the weld, the faster you have to move and reposition. Took me many, many welds to get to the point of them looking good.

Keep on burning rods and it will come with time.

Scott

I see what you mean. I suppose that welding on a convex (2" ball) surface only complicates matters.

You are in essence in my back yard stop by any time BYOB I will help you out with welding on any type os steal you want Mig,Tig, Ark,Heli-ark ,oxy-act, even show ya how to dry out oil & wet rods . just let me know when you wish to come by .

Sam

Some people mistake underfill for undercut and vica versa.... Underfill is the obvious; the weld joint (or bead) not filled to its entirety. If this is the case, the fix is simple; go slower. Undercut is melting the base metal away to get good fusion but not filling it back with weld metal. It can be caused by a few things but since you're a beginner, i would say its from too long of an arc length (especially with your 7018's). Keep the tip of the electrode no more than the electrode thickness off the base metal. That's a good place to start. Once you practice more, you'll get it!

-Hillbilly

the only 2 cents i have on this is slow down, watch the edges of the weldpool and move slow enough that when you see the undercut happening move slow enough that you see it filled. also im pretty sure you can run 7018 A/C but you need to do it at low ampers.

7018 comes two ways,,one marked AC and one DC.

You are in essence in my back yard stop by any time BYOB I will help you out with welding on any type os steal you want Mig,Tig, Ark,Heli-ark ,oxy-act, even show ya how to dry out oil & wet rods . just let me know when you wish to come by .

Sam

 

I Guess you are a bit busy to accept the offer ?  It still stands to help you .

 

Sam

I Guess you are a bit busy to accept the offer ?  It still stands to help you .

 

Sam

 

 

Sam,

 

Sorry I didn't respond to your post last April. I was in the heat of trying to finish that particular job and got distracted.

 

I certainly appreciate the offer. But you are right about the busy part. My schedule and my good intentions don't work well together :wacko:

 

I wil definitely try to take you up on a visit if things ever lighten up.

 

I appreciate it,

 

Don

No Problem Don I would rather be busy then not working . ;)

 

Sam