[SkyDawg]

More recent T-joint, still having an issue finishing the weld, but feel like its getting a little better

rps20130620_044830_337.jpg (106.53 KiB) Viewed 1381 times

One of my earlier Vertical up Welds clearly with the problem stated

rps20130620_044730_303.jpg (66.43 KiB) Viewed 1381 times

I'm new to the forum but have been viewing Jody videos for a while, great stuff. My question regarding Vert up 7018 is finishing the weld. I've been welding in class..mainly T-joints..I don't have any pics at the moment but can get some soon. When I get to the very end (top), the heat (I think) becomes a problem and my weld sometimes begins to droop, how do I prevent this? Should I just let the metal cool?

[Otto Nobedder]

I typically "pull out" and stop at the top, leaving the crater until the color just begins to fade, then restrike and button off the weld. I break the arc, pause for about a second, and strike again. (This is usually fast enough for the rod to relight without having to scratch the slag off).

Steve S

[SkyDawg]

Steve, appreciate the tips man. I'm gonna have to try that, I took a test in class which came out much better than when I first started welding Vertical Up. If i can get these pics posted obviously it will help. But I definitely understand what you're saying, I'd probably have to give it a few tries, cuz that's something I've never really thought of...thanks alot man.

[Otto Nobedder]

An "auto-dark" hood helps with accuracy on the relight, though if you can't see it through a fixed lens, you may have waited too long.

On thinner material, this "stop, pause, button off" can be repeated a few times to eliminate that crater at the top, and even wrap around to the other side.

The pic of the recent try looks much better than the other. You can even restrike and hold a fairly long arc at the top to "drip" into the crater.

You seem to have it... It's just trial-and-error and practice from here.

Let us know how it goes.

Steve S

[SkyDawg]

Thx for the advice, I'll definitely put it to use. Another good suggestion with the long arc, always appreciate it...

[Alexa]

Thx for the advice, I'll definitely put it to use. Another good suggestion with the long arc, always appreciate it...

=====

SkyDawg.

If you are using low hydrogen rod (example 7018), it is recommended to not use a long arc, for the risk of porosity. (Even though there might result porosity, it does not mean that the weld is unacceptable ... this depends upon the acceptance criteria.) My guess, is that you could still move upwards, slightly over the top of the tee-joint, with a normal arc, and allow the metal to flow (drip) downwards to fill the joint.

To a certain degree, the discussion may be academic, in that in production, you might well have run-off tabs in place to avoid this difficulty. In the case of test joints, the beginning and ends of the welds are cut off and discarded, so even if there is porosity, it would not be tested.

Tanks.
Alexa

[Otto Nobedder]

Alexa,

For clarification, I simply meant a longer arc than normal, solely to button off the weld in the pictures, T-joint with no run-off. No exceptional length of arc, just beyond normal to disperse the arc-force and heat to fill the crater.

And, yes, it's easier to say than to do...

Steve S

[SkyDawg]

Alexa,
Thx for the input. This weld was driving me crazy when I first began practicing it. I felt that my rod angle and speed of travel was fine, I just couldn't understand why it would begin to melt/crater when I got to the very top. I undertood exactly what Steve was sayin with the breaking of the arc, restarting quickly and button it off. And with your explanation Alexa, that is exactly what my teacher taught us, hold the arc over the top and have it drip/fill in the top...like I said, it was giving me hell b/c the rest of the weld came out alright. In talking with a few of my pipefitter buddies, they were saying that with this Tjoint, the heat has nowhere to go so that might be the issue, so I started to let it cool. That and I changed my weave pattern which made a difference for me. I will definitely put all of these suggestions to use, the more practice and the different techniques should help me find my way. Much obliged to both of you.

[Otto Nobedder]

Your pipe buddies were right... at the top of the joint the heat has no more "ahead" to go, only behind and sideways, so the metal has nearly twice the heat saturation. That's why a first try at that weld often results in a dripout or sag at the top. It's also why the stop/pause/relight helps fill it in... You're putting in half the heat.

I should point out that all advice, tips, and even what you learn in school are just starting points toward developing your own technique as you find what works best for you. No two of us do it exactly alike (except perhaps when we first start learning).

You'll notice reading some of these topics that some of the advice, from very experienced welders, seems to condtradict one another. That's just how wide the spectrum of "ways to do it right" is.

That's another great benefit of this forum. You get all points of view with no one so "married" to their way of doing something that they'll put down another's method, like I've seen on some of the big forums.

Steve S

[SkyDawg]

Exactly Steve, that's what makes these forums so great. Takin little bits of info from different welders who have a lot of experience and putting the the tips to work, finding what works best for me. Thx again, I'm sure ill have more questions in the future...