A different way to add filler (OA)

In another thread, someone suggested Elza's "Aircraft Welding" as a good read. I got it from Lindsey Publications and am finding it very helpful. There is a section in the back devoted to step-by-step exercises in learning different OA procedures/welds. The book was apparently designed for students in the Wichita school system who were headed for welding jobs at the Boeing plant (1942).

One thing he says is counter to the 'dab the filler into the molten steel puddle" school: "The puddle is started as in the preceding exercise, and, after it has been established, the end of the rod is applied to the front edge of the puddle. ... The molten end should at all times be in contact with the front edge of the puddle. In other words, the metal from the rod should be continually flowing into the puddle rather than being added in drops."

Pros/cons/comments? This method is certainly easier than dab,dab,dab. - Mike

Reply to
mhorowit
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Isnt this basically the 'walking the rod' technique. Once I get a puddle, I introduce the rod to it with a slight downward force. I can then feel the rod collapse as I proceed the puddle down the path. It feels as though the rod has perferations. The result is a nice rippled bead with ferrous materials but not as good with Al (for me, recently someone suggested to me that they wel Al this way but i haven't seen the results).

Reply to
cl

On the few occasions I've welded aluminum, that is how I've done it. The result is not pretty. The front face ends up thick and blobby, while the back side is somewhat irregular. But it does work. If, like me, you can't be sure when the aluminum is ready to go--I know it's molten only when it falls through--poking the work until the rod sinks in and then walking the rod lets you join two pieces of aluminum NOW, when you need it, rather than after you've gained the skill to make it nice. I doubt that anyone would do it that way by choice.

FWIW.

Owen Davies

Reply to
Owen Davies

Owen Davies wrote: I know it's molten only

After my initial concerns a few months ago about weldability of aluminum (I've learn alot more than I bargained for :) ), I feel very confident in reading the Al puddle. The special glasses are necessary but you don't have to have the most expensive ones. I've gotten to the point where sometimes I can produce beads that look robotic on .025-.035 Al sheet (very small coupons at that, 1.5x2 inchs joined!) . Ripples and all. It is a very frustrating ride and took a about 80-100hr of torch time to feel good about it. You really learn a level of heat control that translates back to being good at joining just about anything with O/A and getting TIG like appearance It is also nice being able to do filets on 1/4 Al and not having to worry about having enough power!

That said, I've found the envelope will melt the al filler before the puddle forms completely so I haven't been to exicted with the result. With steel this isn't an issue but the hot-shortness of aluminum doesn't allow you to work the filler in, you have to keep moving--or else. Controlling the speed of the torch is crucial as is adding the filler (same as you do with tig) with a fluid like repetive motion to freeze the puddle. Once you learn to recognize the puddle wrinkly satin look, you can control it like with steel. The glasses are necessary for this and I have been told that the TM2000 make the puddle easier to see than I can with the cheaper cobra specs like I have.

Reply to
cl

That methods is suited better to filling large holes, or gaps. In general it puts more heat into the base metal, hence more distortion.

It is also more difficult to get a uniform weld bead.

Reply to
Ernie Leimkuhler

I was taught this technique by my welding instructor. He taught us to move the tip of the rod further into the pool to increase buildup (and reduce penetration) and closer to the leading edge of the pool to decrease buildup (and increase penetration). It makes an attractive, even bead.

Reply to
John

I tried something different last night and was amazed at the result.

I decide to backhand O/A weld 1/8 aluminum. The very first attempt gave me a bead appearance that you would not be able to tell was not tigged (well there is a slightly smoother look ). This contrary to normal practice for aluminum but the puddle freeze looks great. Normally my ripples are barely discernible. These ripples have great definition but not like one that i can normally emulate that are the result of too much filler and a cooler less penetrating weld. Granted, the flatter or robotic welds I've been getting are better strength wise, these had great appearance without compromising penetration

Yes, I'm making an art out of O/A aluminum welding appearance. :) Now I get to try backhand on thin Al .035 sheet :D

Reply to
cl

What rods are you using?

D> I tried something different last night and was amazed at the result. >

Reply to
Don W

1/16 and 3/32 4043 Tig rods
Reply to
cl

Are you using any flux to inhibit oxide growth, or are you using the rods bare?

I'm looking to give your method a try, and want to make sure that I'm doing it the same way you are.

D>

Reply to
Don W

Yeah, you have to use the flux. Watch the video on cuts like plasma

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You need the special glasses and alot of patience. I thought it was futile at first but now it is pretty easy.

Reply to
cl

Thanks for the links. I've been OA welding aluminum using special flux coated rods made for stick welding. The results have been good. I liked the video using the Henrob torch.

D>

Reply to
Don W

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