to point or not

I posted this over on the Miller site (Ask Andy) but didnt get an answer so I thought Id put the question to the news group:

Now that I have my TIG setup working and Ive messed about a bit I have a question about pointing the electrode. It seems that all texts say the electrode should be pointed. However, they never explain exactly why. So, I did point it checmically and found that the longer and thinner the point the wider the arc. I also tryed not pointing which gave a very narrow arc. I liked this one the best. In fact I could throttle back a bit using a blunt electrode (face 90 degrees to the edge). What I experienced is consistant w/ what the Miller TIG handbook says about pointing. So, why exactly do you need to point the electrode? Not doing so works well. The TIG book says pointing is handy for welding thin sections. However couldnt you get the same result by welding at a lower amperage?

Reply to
Jim Goddard
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Most pionts are ground on a bench grinder. What angle are your points how, what type, size, pol. of weld?

Reply to
Lance

From what I know the chemical sharpener works just fine. I havent heard any complains. unpointed (end 90deg to the edge), Lanthanated 1.5%,

1/16", DCEN

Lance wrote:

Reply to
Jim Goddard

What machine? What are you welding?

Pointingthe tungsten widens the arc, but also alows much easier arc starting and better arc control.

go here and read up on the basics of tungsten geometry

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Reply to
Ernie Leimkuhler

Maxstar 200DX

Right now only steel.

Thats what the books say and Ive read them (well most of them). OTOH I didnt have any problem doing autogenous welds or starting an arc w/ an unpointed electrode. Im just trying to understand WHY theres any need to point. Thats the part where the books start hand waving. I found a narrow arc made it far easier to see what was going on and control the puddle. I didnt experience any problems w/ arc wander.

subject. The way its written, pointing angles seem to be more of a suggestion or choice left to the welder to decide. They never indicate WHY a point is necessary or how to make a reasoned choice on point angle. Thats fine if pointing is necessary but doing something blindly w/o really understanding why is limiting.

Reply to
Jim Goddard

I think that if you look closely, you'll find that the arc is actually emanating from a corner on your "unsharpened" electrode. This is where the field intensity is greatest and where the shielding gas will first ionize. As you continue to weld, the arc will continue to come off this corner but anywhere around the circumference of the electrode depending upon how you move/manipulate the torch. If you sharpen the electrode, you will ease the arc starting since you can sharpen the electrode to a sharper point than the corner of an unsharpened one. More importantly, though, the arc will consistently come off the exact same point on the electrode. The importance of this becomes more apparent when you are manipulating the torch in a complex weld, say a corner fillet. Having the arc come off the electrode at the same point regardless of how you manipulate the torch gives you one less variable to worry about and to compensate for. Using an unsharpened electrode is sorta like trying to drive a car with a lot of play in the steering. You can do it but it gets real difficult when you start to do performance stuff.

Reply to
Terry Mayhugh

Well if you play with tip point angles you will find that a point of the same taper of a pencil tip is about perfect for general use.

I can't imagine trying to weld a fillet without a pointed tungsten.

Reply to
Ernie Leimkuhler

Reply to
jimg

I'm not an expert TIG welder by any stretch of the imagination, but I agree with Ernie here 100% about fillet welds. I also questioned the pointedness question as you have. But the more different stuff you do, the more apparent it will become. Believe me when I say that if the professionals do it, then there is a reason for it. They don't do stuff that isn't important and waste their time.

Lane

Reply to
Lane

OK, fair enough. I should do that to be complete. BTW have you ever messed w/ angles in your work?

Hmmm...I think Ill give it a try and see how hard this is. So far Ive only done stringer beads and edges.

Reply to
jimg

:) Neither am I but Im having fun learning.

Fair enough. I was doing stringers and edges. Ill try a fillet and see how that runs.

:) Yes and no. I dont want to go too far w/ this but Ive watched pros and amateurs alike misapply rote learning. A good indication someone doesnt understand is when they cant explain clearly why theyre doing something a certain way. A non-answer is 'Thats the way its always done'. It might be perfectly true the method is correct but its the reasons why its correct that are wanted. No matter how skilled you are theres always room to learn and understand. I think if you understand the whys of your work then you have a bigger tool kit to solve the problems you run into everyday.

Reply to
jimg

Yes I have adjusted the grind angle of my tungstens many times. I never do anything without a good reason. I have been tig welding for 20 years as of this fall, and have tried just about everything on these machines.

Reply to
Ernie Leimkuhler

Reply to
rodney johnson

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