New to Tig - pointers please :)

[Stephen Giles]

Hello,

i'm new to TIG welding,
i was doing these fillet welds yesterday, is my arc length too long? i was having to chase the weld pool along and get it to adhere to both plates. I struggled to get it to auto weld and the pool to form in the root of the joint without filler. I have a feeling there was too much filler in there.

Welding 3mm mild steel, the steel was pretty clean prior to weld, but was dull grey afterwards (too much heat?) Parts of the steel were cherry red once i finished one of the welds which i presume is not normal for TIG as i am trying to keep a tight arc length and small weld pool?

There is so much going on that i ran out of rod in my left hand and forgot to feed it, so i circled the tip, am i better to just stop the weld, and resume where i left off rather that pouring more heat into the material?

Number 8 shroud, with a purple sharp clean tungsten, 5LPM Ar flow, with 5 sec post flow.

first image is a bit better weld, 2nd image, the weld got far too hot!

any suggestions and tips welcome.

Thanks!

Stephen.

 

[langy]

I've seen a lot worse so your on the right track, yes arc length is crucial to keep tight, I would increase your post flow also

 

[Stephen Giles]

thanks langy,
at least i know i am going in the right direction.
i'll keep with it.

 

[Richard.]

Fillet welds are challenging with Tig not a great joint to start on. A good technique to do is turn the plate so that your welding pulling the torch towards your body. The ceramic cup should be in contact with both walls of the joint. Now your nice and set for a good run. Keeping a short arc length and the cup rubbing on the walls keep the filler low and dab it in the pool at consistent intervals while pulling the torch slowly towards you. Much easier to show than explain mind. Good luck

 

[Jim Davey]

Dragging the ceramic is a bad habit, it's necessary at times but it's best avoided lest you pick up bad habits, if you position yourself so you can see the tungsten and arc clearly it will be much easier to 'steer' the arc i tithe centre of the root and you'll have greater control of travel speed and arc length if the ceramic isn't dragging on the job.
i know people walk the cup etc but when you're learning to weld then developing good hand-eye coordination techniques without cheats really helps as early habits are hard to break.

 

[Richard.]

Disagree Jim. Using the two surfaces of the plate helps people who are learning to control arc length. It's not a bad habit at all its making life easy for yourself when learning the basics of consistancy
Not walking the cup just gently let the cup touch the two surfaces of the fillet joint to keep the arc length.
It's how I was taught and I'm not stuck with bad habits

 

[Jim Davey]

It doesn't help you to control arc length running the torch along the job. Maintaining a consistent height above the workpiece by hand does that, along with lots of practice. Plus you're far more likely to overheat the end of the ceramic causing gas problems unless you are welding at low amperages. That drag technique can be very handy at times but if the arc wanders from one plate to the other or the ceramic binds then skids as it tends to on ally then it can cause more problems than it solves and harder to quickly reposition the torch to direct the arc just where you want it.
Also, in my experience people who drag the cup on the job are more likely to pull the trailing edge of their ceramic into the still solidifying weld when welding on the flat leaving an unsightly gouge in their weld if they don't develop the necessary depth perception to control all important things like torch angle and arc length.
You can do whatever you want to do to get the job done, all I'm saying is it's a really, really useful skill to build up your freehand welding ability first and foremost, before trying to move on to seemingly easier ways of doing things like dragging the cup.
Just my 2p worth.

 

[Richard.]

Free hand Tig will come with time. I started out by learning where the arc needs to be using the edges of the plate as a guide. This helped me develop free hand technique many years ago I've also used this advise to help others in the past and for me and them it's worked. It's the same when learning to cut straight. Start off with a edge to understand where you need to be then take the edge away when you no longer need it. I learned to ride a bike with stabilisers I don't however still use them.

 

[Richard.]

Just so we are clear I am only referring to the fillet joint where it's very unlikely the ceramic will touch the weld.

 

[Jim Davey]

Everybody's different, let's just agree you've got your way and I've got mine and leave it at that

 

[Richard.]

Yep he's got a couple of ideas to think about which is what's important. I've got a question though Jim slightly off topic the heating consumable cabs you make. Can they be built on a much smaller size just for a small selection of Tig rods.

 

[Jim Davey]

Yes quite easily, I've made them out of lockers before now and the rods are stored vertically, or they can be positioned horizontally with shelves. The tube heaters are very compact and come in a handy range of lengths to suit different applications.
All I need to know is how many tubes or boxes of rods need to fit in and I can work out the size of the box to suit.

 

[Richard.]

Well I would say I keep around 3 tubes of Alu 3 tubes of stainless and 1 maybe 2 of steel. I'm going to have another 2 electrical points in my garage by summer so it's nice to know you can tailor them to my needs. Can you work out a rough cost for me please mate and I'll seriously consider it as I think they are awsome and looking at your pics they are made nicely.

 

[Jim Davey]

Sure thing Richard, I'll sit down and rough out an estimate next week.

Thanks

 

[Stephen Giles]

thanks for the additional pointers.

Stephen.