Problem balling tungsten when welding - Lateral-g Forums

Rhino · #1 05-14-2012, 11:14 AM

I recently picked up a Diversion 180 and am practicing tig by building a new cart. Things are going ok so far considering I haven't picked up the torch in 15 years. One issue I'm having is I can't seem to keep my tungsten sharp. After a few minutes of welding I notice the tip balling, and it only gets worse over time. I can go about 10 minutes before having to resharpen.

Is this considered normal? Is there anything I can do to avoid the issue? I've previously only tig'd Aluminum and I was instructed to ball the tungsten on purpose.
I'm welding a combination of .120 wall 1" square and angle mild steel. The machine is set at a max of 80 amps to form a puddle quicker at the start, but I'm only using about 3/4 of that to keep the puddle moving. I'm using the ceriated tungsten (unsure of size) and #7 hood that came standard in the box in case that matters. After sharpening the tip length is between 2.5 to 3 times the material width. 2.5 is what was suggested in the video.
Any help the guru's could provide would be appreciated.

mad68rs · #2 05-14-2012, 11:53 AM

i wouldn't grind it passed 2.5x the length if you don't have to but that is probably not the issue as long as the collet is making a good seal... i would check the diameter of the tungsten and collet to make sure the are the same size because that seal is what keeps the tungsten cool on air cooled torch... without knowing the diameter of the tungsten it's hard to say, but depending on the diameter of the tungsten you could be at max amperage for it... 80 amps means it would have to be pretty small like... 0.040 diameter. That could cause the end to ball... hope this helps... btw miller's website millerwelds.com is an awesome reference for all things tig welding... they even have a free TIG handbook download

mad68rs · #3 05-14-2012, 12:00 PM

oh and since you mentioned welding aluminum - which you do on AC... make sure you set your machine to DCEN - DC electrode negative... this means about 2/3 of the heat will be in the work and about 1/3 in the tungsten... having the machine set to AC will cause the tungsten to ball, and DCEP - dc electrode postive will put more heat into the tunsten then the work

Rhino · #4 05-14-2012, 02:41 PM

The electrode is well above .040. I'd venture to say it's 1/16 to 3/32. That variance is why I can't say whether the tip length is 2.5 or 3x the width. Looking up the parts list, it appears to be 3/32.
The only reason I mentioned the aluminum is that it was my only tig experience prior to yesterday. At the time the standard seemed to be using a balled electrode. Having never used a sharp electrode I didn't know if this was "normal". As a side note: The one drawback I'm seeing to the diversion so far is that I'm not aware if I can set polarity when running DC.

The tungsten came preinstalled, and there's a decent amount of drag when removing it so I would assume the fit is good. I will verify this evening. I may also try grinding a lower bevel onto it as a test.

You did mention the gas being responsible for cooling the tungsten. It may be that I have too much protrusion from the cup. I noticed the problem worsen when I pulled the electrode out further to get back into a corner more effectively. I'd guess that I'm at around 3/16 outside the cup currently.

**GregWeld** · #5 05-14-2012, 06:31 PM

Aluminum is welded in AC not DC

IF it's an "inverter style" TIG then you DO NOT ball the tungsten.

And don't use GREEN tungsten --- use Ceriated or thoriated. (Red or Orange)

Rhino · #6 05-15-2012, 05:56 AM

Quote:

Originally Posted by GregWeld

Aluminum is welded in AC not DC

IF it's an "inverter style" TIG then you DO NOT ball the tungsten.

And don't use GREEN tungsten --- use Ceriated or thoriated. (Red or Orange)

My experience on Al was almost 15 years ago while in high school. The machine I used previously was not an inverter machine and balling the tungsten seemed to be normal for the time. I am using DC since this is mild steel with a 3/32 Ceriated tungsten.

I think I found the majority of my issue last night. I'm now remembering that there's no such thing as too clean of a weld. I was running a steel brush over the joint, but hadn't been cleaning up the majority of the mill scale.
Years of mig welding has made me a little lax when it comes to cleaning the weld. I believe the majority of what I thought was balling was actually contamination from spray building up on the tip.

I came to that conclusion when I noticed a little porosity in part of my weld. At the same time realized there were a few small sparks flying from the puddle. Once I broke out the flapper wheel and got rid of the mill scale on the front, and back, of the parts in question the process was 100x improved.

**GregWeld** · #7 05-15-2012, 07:21 AM

Ah ha --- Okay --- When you started talking about balling I ASSumed you were welding aluminum.

ONE WARNING --- DO NOT USE CHLORINATED CLEANERS (brake clean etc) to clean you metal. It can kill you with phosgene gas.

Rhino · #8 05-15-2012, 07:45 AM

At this point in time I think it's safe to assume my knowledge of the process is highly limited. Any help is good help.

I did notice that the tunsten prep was different for this machine but didn't really understand the difference until looking into it.

Good call on the brake clean, I hadn't been using it since this metal is "relatively" clean. With that said, I could have easily reached for it without too much of a thought. Do you have a prefered method for cleaning oily metal?

**GregWeld** · #9 05-15-2012, 07:58 AM

I use brake clean -- but I use NON-CHLORINATED

#1 rule in TIG -- CLEAN CLEAN CLEAN CLEAN

This ain't MIG (farmer) welding... TIG is all about tight fit ups - bare - cleaned metal - NO oily residue. This is precision welding.

ASSume you're using Argon gas...

The DIAMETER of your tungsten sets the limits of your heat. So check the amperage ratings of the diameter and type of tungsten you're using.

There's a thread here about tungsten sharpening. There's also a TON of info and videos on Miller and YouTube etc.

Rhino · #10 05-15-2012, 08:46 AM

Quote:

Originally Posted by GregWeld

#1 rule in TIG -- CLEAN CLEAN CLEAN CLEAN

This ain't MIG (farmer) welding... TIG is all about tight fit ups - bare - cleaned metal - NO oily residue. This is precision welding.

Yep, I am using Argon, set at 15 CFH currently. You're absolutely right about cleanliness. As soon as I realized what was going on last night I did have a bit of an aha moment. As soon as I cleaned it up not only did I not get any contamination but the weld laid down so much nicer. Not quite the stack of dimes I see elsewhere, but it's something I can at least be proud of.

It turns out my old shop teacher may have known what he was talking about all along.