Tungsten grinder

[Badger1bear]

hi guys do I actually need a tungsten grinder or is it sufficient to sharpen it up by eye using a grinder ?

 

[Windy Miller]

I do mine on a normal bench grinder. It puts massive grooves in the wheel, but they dress out easy enough.

 

[Badger1bear]

So long as it's a uniform point it's ok :-) what length of point am I looking to get ?

 

[eSCHEn]

About two or three times the diameter of the tungsten. Make sure you grind in line as well.

 

[Paul.]

For DC around 2.5 times the dia of the electrode, its all in here
http://www.mig-welding.co.uk/wiki/DC_Electrode_Preparation

 

[eSCHEn]

Snap! Just about to post that link

 

[Windy Miller]

Read these:

http://www.mig-welding.co.uk/w2/index.php?title=DC_Electrode_Preparation

http://www.mig-welding.co.uk/w2/index.php?title=AC_Electrode_preparation

 

[Badger1bear]

And there was me sitting here with the tungsten in a drill and holding a pencil sharpener lol

 

[Badger1bear]

Is it worth buying a proper sharpener ?

 

[daleyd]

There is a guy on here who made some attachments for a dremel. (Hudmut and his famous tungsten grinders!)

Not strictly necessary but very convenient and fast, and you get excellent consistent results. I've got one and I would highly recommend it.

It's also recommended that whatever grinding wheel you use for tungstens you don't use for plain steel as this can contaminate the tungsten.

 

[Mr shiney]

I will second the Hudmut grinder. Amazing bit of kit giving a consistent result on every tungsten. Made no end of improvement to my TIG work.

 

[Wendelspanswick]

I use the belt on my linisher, if the tungstens are short I hold them in a pin vice to stop me burning my fingers!

 

[hotrodder]

FWIW millions of X-ray quality welds have been made on site using whatever was to hand for tungsten sharpening. While i don't doubt it's possible to contaminate tungstens while grinding them if you try hard enough it's not easy... a soft metal like ally and it's very easy to smear all sorts of crud into it, tungsten on the other hand is 'kin hard

AIUI the origional reasoning behind tungsten grinders was automated TIG. The included angle has an effect on the shape and stability of the arc which in turn effects the weldpools depth to width ratio http://www.pro-fusiononline.com/tungsten/geometry.htm and a pic of macro etches...

Machines drive at the speed they were told to making tungsten geometry an important variable. Humans watch the weldpool and react accordingly so tungsten geometry is more about a trade off between arc stability* and tip longevity; assuming you don't dip it in the weldpool/feed a bunch of wire into it

When 'elf & safety became a bigger deal and people started worrying about radioactive carcinogenic thoriated warnings the companies that made tungsten grinders spotted a new market...

* Arc stability is also effected some by the smoothness of the grind. As Paul said in the DC electrode prep tutorial this usually only becomes a deal at very low amperages. Diamond grinding wheels can be useful here (and unlike Aloxide stons they don't need dressing) but all i've ever done is give the tip a polish using a flap wheel or whatever was to hand when i'm welding stupidly thin stuff along with grinding the tungsten to a longer point

 

[eSCHEn]

@hotrodder I want to ply you with whatever your favourite predilection is and bug you with a million questions about TIG. Once again a super interesting post, thank you.

@Badger1bear I think @arthur was selling a spare hudmut grander not that long ago, I can't remember if it went or not...

 

[Badger1bear]

A grander eh ? As in goosey goosey grander Darren lol

I have sent Arthur a pm

 

[hotrodder]

A couple of pics of something i did years ago when there was a massive debate about tungsten prep for AC on another forum (you want a sharp tungsten, NO it HAS to pure tungsten balled using DCEP etc). Brand new tungsten, zero prep, zero problems although the arc was a bit less stable then usual

 

[eSCHEn]

A grander eh ? As in goosey goosey grander Darren lol

I have sent Arthur a pm

Gah, bloody sausage fingers!

A couple of pics of something i did years ago when there was a massive debate about tungsten prep for AC on another forum (you want a sharp tungsten, NO it HAS to pure tungsten balled using DCEP etc). Brand new tungsten, zero prep, zero problems although the arc was a bit less stable then usual

You know what I have done the exact same test on DC and yes, the arc is awful and more jittery than an addict going cold turkey, but you can put a reasonable bead down nonetheless. I wouldn't put that one on the same category as mine though - I dream of producing ones that nice lol!

 

[gordon stephenson]

Simon, for a man of your obvious discerning nature you deserve a Hudmut tungsten grinder to fit right in with your stable of Lorch machines.

 

[Pete.]

One big advantage of using a diamond wheel is if you dip the tungsten and get that big ally blob on it you can use the corner of the wheel to cut the tungsten off and save a stack of grinding.

Or so I've heard anyway....

Plus of course the wheels are great for sharpening carbide lathe tools.

 

[Badger1bear]

Simon, for a man of your obvious discerning nature you deserve a Hudmut tungsten grinder to fit right in with your stable of Lorch machines.

the deal has been done Gordon