Tig practise

[bluebobtail]

Well i finished my nvq level 2 last week, so thought i'd practise some tig work as i'm hoping to go back to college next term to do the tig level 1.

Welding mild steel about 3mm
Using about 75 amps with 1.6 filler

Now i could lay down 3 straight welds with the help of a line on the steel.
So i turned to the next test piece, a lap joint. Left the amps at 75 and managed to crack it on the third attempt.
Next was the fillet. Now this im struggling on. I tried it at 80 amps and 85 but found there was way to much undercut especially on the vertical edge.
I then tried again dropping it down to 75 again but again undercut on the vertical.
Im adding the filler from the vertical edge but its just as bad.
Should i drop the amps a little more and move slower or shall i add more filler?

Ill post some pics up next week after ive been on thursday night.
Any advice would be appreciated.
Thanks
Ian

 

[pedrobedro]

Your 1.6 filler is too thin for 3mm steel you will struggle to get enough in there at the amps you are running.

 

[bluebobtail]

Well College was back on this week but its my last week next week.
But i'm hoping to enroll back in January for the next term and do my nvq in tig welding.
Here are some photos from this week.
The last 2 photos are of the same weld.
But i seemed to get a feel for it.
I slowed right down added the filler to the top of the puddle then let it flow before moving on.
On the previous welds i think i was moving to quickly, too higher a amps and not enough filler.
It all just made more sense in the end and it looked much better.

I hope im doing ok.

The lecturer is recommending i go for level 2 in the tig and if i struggle we will just put in the level 1 stuff.
Any comments appreciated.
Thanks
Ian

 

[hotrodder]

Are you sectioning and etching the welds yet?

Should i drop the amps a little more and move slower or shall i add more filler?

If you're comfortable(ish) with torch and puddle control I'd try upping the amperage a bit- as well as the undercut you mention there's missed edges and underfill, especially on the outside corner. A few more amps will give you a puddle that can be fed without it cooling too much, running a bit hotter would let you use 2.4 wire as suggested but 1.6 is fine- swings and roundabouts as 2.4 is likely to be a bit 'sticky' when running at the cool end amperage wise but you'll need to feed more 1.6

The arc length thread may be of some help for the fillets if you've not seen it yet.

 

[bluebobtail]

Thanks for that, i must be having the arc length to long as when tacking or starting the weld i get 2 puddles rather than just the 1.
Arc start is set at 50 amps for 1 min i think with the same on the down slope.
Welding amps is about 70 to 75amps.
Ill try upping the amps next week shorten my arc length and add more filler.

I best not tell anyone else i can now multi task

 

[hotrodder]

Collar an instructer and make 'em watch you tack up and weld a fillet if possible- they'll be in a better position to advise

From look of the fillets arc length isn't miles out but i suspect is a bit inconsistant. With 70-75A being a bit low for 3mm i'm not suprised you're getting 2 weldpools initially

 

[bluebobtail]

Thanks for that,
Ill try and get some more pics on thursday of my new efforts.
Then ill have to practice at home over xmas.

 

[Jackel]

Which college are you at?

 

[bluebobtail]

Im at hartlepool on a thursday night

 

[Jackel]

Ahhh you'll know Geoff then

 

[brightspark]

Im at hartlepool on a thursday night

wach out for monkey hangers

 

[bluebobtail]

Yeah Geof is still there, he had his pace maker changed a couple of weeks ago.


Im getting there with my consistency now. Its position i'm struggling with now.
I find it easier at home as i have a foot pedal, which is great for aluminium.
Well i hope i get it next year. Have enrolled to do tig level 2.

 

[Jackel]

Yeah Geof is still there, he had his pace maker changed a couple of weeks ago.


Im getting there with my consistency now. Its position i'm struggling with now.
I find it easier at home as i have a foot pedal, which is great for aluminium.
Well i hope i get it next year. Have enrolled to do tig level 2.

Ask him about Carl with the beard on a tuesday at Boro....Thats me

 

[Freshfabrications]

Where ever possible, ie when your not hanging from your ears upside down in a lift shaft, you should be using a foot pedal. The preivous advice re amperage is correct, I'd ask your tutors nicely for a bunch of practice plate and get some ER70S-2 rod in both 1.6 & 2.4 take it home & set your machine to about 120-130 amps and use the foot pedal, play about and see how it feels. If your tigging ally think about how you feed the rod with that, how you feed in untill it has slightly more reinforcement some of which travels forwards with the pool as you advance along the seam, it wasn't untill I started tigging ally that I really learned to feed the pool well. This should help lessen the undercut, also don't just go 45 degrees with the torch in the fillet, instead bias the arc slightly towards the flat (not the vertical), remember almost all welding defects can be traced to poor welder technique, so if it looks wrong try it a different way, this is how we learn...

Hope this helps

 

[bluebobtail]

Thanks for that.
I completed my first test piece last week for level 2 on the tig, tried lots of different ways but just couldnt get it.
It was a butt joint horizontal on 3mm mild steel.
A lot of my problem wasn't with the root, i was getting plenty of penetration, but with to much filler so had a very high or lumpy root.
Changed my technique and got it.
so needless to say im very pleased.
I'd love to practise more at home but gas is so expensive.

Thanks again, i'll try and take some photo's this week.

 

[bluebobtail]

Well second test piece done and passed.
had a go at my third on some scrap but to much undercut but was my first attempt.


Jackel are they doing any courses next year. I'd like to do some more in september if i pass my tig level 2.
Hopefully ally welding maybe level 1 then see what happens.

 

[Jackel]

best ask Geoff bud as I've run out of courses to do at Boro

 

[bluebobtail]

Thanks Jackel
Here are a few more pic's from this week.
Didnt complete my test piece this week but my welds are becoming neater, or at least i think so. Have brought some metal home with me this week to try and get some practise in.

My main problem i'm having is undercut on one side.
The weld is a vertical fillet 3mm mild steel.
Amps vary from 75 down to 72
Sorry if the photos are not very good i was starting to get fustrated

 

[Delgado]

Looks like you're starting to get the hang of it!

Try grinding the mill scale off the area to be welded before you start and you'll find it makes the world of difference with regards to the undercut, also makes it easier to see and controll the weld pool because it don't have loads of crud spinning around in it. Could also be other issues, but I'd start with that.

 

[Freshfabrications]

Looking good, I take it your left handed from the photos.

Looking at the pics, the ones with under cut, you can see that the shape of the bead isn't really as rounded as it could be and it's a little wibblie, it's a bit of an arrow/slouching C shape, this indicates one problem that is torch angle and that your not steadying your hand enough, the spacings look good enough but also your not adding quite enough metal to the ones with undercut, so play a little with your torch angle of attack until you get a nice equal shaped "C" and add a good reinforcement with the filler. Remember to always watch the shape and fluidity of your weld pool and adjust your angles and amps to keepit comfortable.

The other pics have perhaps more filler but I would sugest that for that amount of filler, which looks correct, you should be running a few more amps to get the fillet to blend nicely with the parent material.

This doesn't come over night so keep practicing, very good for a beginner!!