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View Full Version : Tungsten Grinding ( Hazards? Safe practices?)



Rich05
11-30-2007, 12:04 PM
I have been practicing TIG welding in my garage, so far with aluminum. I don't grind my Tungsten Electrodes very much but have about 30-50 times without using a mask. How bad is this?

now I find out this is a bad thing. so I am using a mask, however I am worried about particles that may float around my shop after grinding.

Being new to this wondering is this over-reacting? Is it needed to by an expensive grinder? How can this nasty stuff be handled properly in a garage/home situation?

Thanks R.

tmarks11
11-30-2007, 03:31 PM
WRT thoriated tungsten grinding, read this rant:

http://www.weldingweb.com/showthread.php?t=13000


Yes, you are over-reacting. You will pick up more alpha particles in your lungs from walking by someone who is smoking then from spending all day in your shop. If your job title was "tungsten sharpener", and that was all you did all day long, you probably still would not have a problem. Keep the grinding dust in your shop at a manageable level. Keep the dust out of your lungs by wearing a respirator if you are going to be doing alot of grinding. If you use a bench ghrinder for sharpening, clamp a dust collection tube on the discharge port of your grinder and put it in a bucket so all the dust collects in one place. Or use ceriated tungsten. But I will keep using thorated.

Rich05
12-05-2007, 12:26 PM
thanks for the good info. I bought a Sharpie grinder. the standard model for $250. Somewhat of a luxury I know..

http://www.arc-zone.com/index.php?main_page=index&cPath=15_165

Well here goes another dumb question. If one is going to go to all the trouble of buying a Tungston grinder would it make sense to pay the additional $200 to get one that has a vacuum bag in it? That one is $375...

Thanks R

tmarks11
12-05-2007, 01:01 PM
I wouldn't. That is alot of extra money for very little value added. Consider it a tax on your gullibility... I think you passed!

Wish I had a sharpener like you bought. Just hold the sharpener over the trash can and you will be good to go.

I am assuming that as I get better at TIG I will be sharpening less and less...

Rich05
12-05-2007, 01:18 PM
The Sharpie looks nicely made. Yet to try it. Anything that can make the process easier allways seems like the way to go. I was grinding the electrode on my grinding wheel the other day it was bouncing around and not perfectly connical. So this should be a nice tool.

mxtras
12-05-2007, 02:16 PM
Grind with decent ventilation.

What tungsten are you grinding?

Scott

Rich05
12-05-2007, 02:22 PM
Red (thoriated) for steel.

Green pure for aluminum (no idea why Airgas sold it to me since now I hear that is not great since it balls up to easy).. Still have a couple 10 packs of those so going to take forever to use them up.

planebuilder
12-06-2007, 11:09 PM
I don't understand the problem. I have been welding aluminum with pure (green) tungston for 20 years. I have tried other electrodes, discarded them as sales hype!
Why grind? Grinding is for 2% thoriated for steel welding. For aluminum just hold the electrode with GOOD pliers, break off the contaminated end of the pure tungston with a sharp rap on the edge of a steel top table,( don't get the scrap in your eyes), and start welding, a "ball" will form very quickly, that is what you want on the end of the electrode for aluminum welding!

bekx
12-07-2007, 12:41 PM
u can use the grey electrodes for aluminium/stainless/steel. they are not bad for health.

i'm welding aluminium for about 5 months allmost self teached, but i think something is wrong when the ball forms on the tip of the electrodes, it could be u are welding at a high curent with a thin electrode, the freq is too low or the balance is on the cleaning.

tullsa
12-27-2007, 02:29 AM
just a note about the finish on the tungsten ,if after grinding you do a 20 to 30 seconds of polishing the weld will come out much smoother and I use a new polished tungsten on every weld .I have a 8,000 dollar machine that does a good job but now go to my supllier to get pre sharpened tungstens

mxtras
01-02-2008, 04:04 PM
I must make a few comments here.

First - pure tungsten is for AC on aluminum when using a transformer machine. If you are using an inverter machine, you will have better tungsten life using 2% Thoriated - even on AC. I will still use pure even on an inverter but I rarely weld with an inverter.

2% Thoriated is identified by a RED band
2% Lanthanated is identified by a BLUE band
Pure is identified by a GREEN band

Many folks use 2% Thoriated for aluminum. It's very common. Some folks do not have anything other that 2%T for their TIGs and they use it to weld everything. It is very versatile and durable. Same is true of the 2% Lanthanated.

Pure tungsten will ball up on AC. It's normal. If the ball is more than ~1.125X the diameter of the tungsten, you are using too small of a diameter for the amperage. Go to the next larger diameter or use 2% Thoriated.

Polishing the grind on a tungsten is great for about 20 seconds of welding unless your grind is rough and fauceted. Beyond that, normal errosion of the tungsten nullifies the polish and it becomes ineffective. Grind clean and true on a smooth wheel and call it done.

Scott

mike944
01-09-2008, 02:36 PM
I agree with BEKX - if a ball starts to form, that means it's time to stop and re-grind. I use thoriated for aluminum, on an old sinewave machine. It stays fairly sharp for quite a while. I have a lot of difficulty controlling the heat with a balled-up pure tungsten. Tried it a few times, since it's the "traditional" way of tig'ing aluminum, but i gave up trying.

For an inverter machine, frankly, i use whatever i have laying around, regardless of the metal. I don't notice any difference using any of the variations. (never tried pure with an inverter though)

As to the danger of grinding thoriated, i never worried about it. the radiation level is very, very low. I once read somewhere that if you're using up less than 10 packs a year (100 electrodes) you don't have anything to worry about. I'll be lucky if i use up one pack a year.

Toysrme
01-19-2008, 11:46 PM
2% thoriated (red) for DCEN steels, grinding dust is radioactive, but longest useable life
2% ceriated (orange) for DCEN steels and AC welding on inverter units, not radioative.
1-1.5-2% lanthanated (black, gold, blue) for DCEN steels. not radioative.
Pure tungstens (green) for AC welding on transformer units.
Zirconiated (brown) for AC xray **** you'll never do.


If you're using an ancient transformer rectifier based tig that weighs 500lbs. Then use pure tungsten.
Most newer inverter machines in use now a days will weld much, much better using Ceriated, Lanthanated, and a *few* will do Thoriated. You'll get increased tungsten life (higher working temp). But mainly MUCH improved arc control and concentration, as you no longer ball the tungsten. You use it tapered with a truncated tip.

I'm not the biggest fan of grinding machines. We just spent $1200 on a nice water cooled machine that takes too long to correctly grind a tip. Worse yet, everyone has come to the realization after afew uses that it takes just as much operater skill as a manual grind.t's only positive is that once an operater get's it down there is a hair less tungsten consumed in the process.




Thoriated is great because it's very cheap, very common, and has the highest operating temperature of them all. Making it the longest lived. Wear a mask if you're afraid of it, but unless you're gtaw for a living you've got nothing to worry about.

Toysrme
01-19-2008, 11:52 PM
To add to that, if you're welding aluminum. Once a grinding wheel has touched steel. It no longer touches anything aluminum, especially a tungsten.

And that you're most likely to die of the wood dust/particles floating in a shop due to vastly inadiquate ventallation than you are metal / tungsten particles. Metal particles might put your eyes out, but they're not generally going to be found in your lungs. (along with wood chips)

http://billpentz.com/woodworking/cyclone/index.cfm


http://billpentz.com/woodworking/cyclone/medicalrisks.cfm