Tungsten question

[lightn95]

I picked up an Alpha Tig about a month ago and it's going pretty good but I've got some questions about the tungsten.
How often do you stop and re sharpen? I use the Estwood sharpener.

How do you cut or break the tungsten? A couple times the tungsten has turned black about 1/4" up from the point. I've read that you don't want to use it when it's black. I'm ordering a CK torch today with a stubby kit and I'll need a shorter tungsten.

Thanks for the help.

 

[bad_idea]

Cut with a grinder. You can score it and break it off but there is a good chance it will fracture. We use a flat back cap for welding pipe in place, so all of our tungsten is cut short. How often you sharpen it will depend on your skill. I recommend you sharpen several pieces and keep them in a tube together. Either a case single larger drill bits come in (usually red or green and two halves that slide together), or make a tube with a piece of 3/4" PVC with one cap glued on and the other slid on. Sharpen all the tungsten at once then swap as needed. Will reduce the time wasted sharpening in the middle of a job.

 

[dr_clyde]

I sharpen when needed. Sometimes I can go hours with no problem, then sometimes I immediately foul up a fresh tip.

How often will depend on a lot of factors. Primary factor is how skilled you are at not contaminating the electrode. Obviously there are other factors, like if you run into a pocket of crud, welding zinc plated metal, or are using scratch start. My old professor Brian used to say that he tried to just sharpen once a day if possible. He obviously was very good at welding and rarely contaminated.

Something is going wrong if you're getting black tungsten. Either you're touching the metal too much and getting burnt metal on it, or something is seriously wrong with your shielding. You shouldn't have any base metal on the electrode, and it should be shiny and clean when you get done welding. If not, up your post flow a bit.

You can clean metal off tungsten if you contaminate real bad, but its usually faster to just break off that little bit. Depends on how bad it its.

If you are using 2% thoriated, you can just put it on the edge of a plate of steel or the table and whack it with a hammer. Thoriated tungsten is brittle enough that it will snap cleanly.

I use 2% ceriated tungsten almost exclusively. It will splinter if not scored pretty deep before breaking. I grind them in half on a bench grinder when they are brand new, and sharpen both ends. I will usually sharpen a half dozen electrodes at once and keep them nearby.

 

[lightn95]

Ok thanks I'll use the grinder to cut them. I usually do sharpen a couple as I go.
I'm assuming the blackness is do to touching the aluminum.. I'm new to this so it happens.. it might also be the post flow. I have it turned down because I thought it helped with the weld after your done welding. I didn't realize it effected the tungsten also.

 

[rlitman]

... it might also be the post flow. I have it turned down because I thought it helped with the weld after your done welding. I didn't realize it effected the tungsten also.

It does. Hot tungsten shouldn't be exposed to air. It'll turn shiny blue if the postflow is way too short. Dull black is more a sign of impurities.

I'll grind a notch around the circumference, and then break it when it's about halfway through. It usually doesn't split then.

 

[matt_i]

Right or wrong I've always broken them flat by placing in a vise with soft jaws and low blow with a hammer right across the jaws.

The guy who gave me a lot of pointers said "you gotta point the heat" when it comes to super thin materials. Which means that there's a balance between the arc-focus of a sharp point vs the amount of heat it can take before it melts to a larger radius. In other words, deeper pedal will snap a wandering arc back into focus but the extra heat could be the wrong thing to do at the time. Stop and sharpen the point and the arc will focus with a lot less pedal, which is important for super thin materials.

 

[Wamsutta]

TIG 101 is a good video.

 

[pi_guy]

The tungsten grinder that I have has a cut off gap or entry position that gives access to wheel.

 

[gofastwclass]

There are days I can't make two inches without dipping the tungsten in something, other days the grinder, tungsten and I only speak a few times. Good thing this is a hobby and not a job.

Any video with Bob Moffat or Jody Collier (welding tips and tricks on YouTube) is going to be a good thing for you to watch and learn from. Those two have forgotten more about welding than most will know and are always sharing their knowledge.

 

[Mekanizm]

I have had a cup that was dirty on the inside contaminate my stuff before.