Getting a constant, steady arc

[dstealth]

At the moment I'm trying my best to get the hang of TIG welding. I have a scratch start DC only Cebora Pocket Pulse 100 and I'm running it on 1.6mm 2% Thor. tungstens and 1.6mm mild steel filler rod. I'm welding 0.7mm mild steel with it.

Problem - As well as trying to overcome the shaky hands syndrome, I'm not getting a steady arc - It either starts wondering once struck or cuts out completely after a couple of seconds, the latter being the most common problem. Metal also builds up quite quickly on the end of the tungsten shortly after sharpening it so it doesn't stay pointy for very long.

Has anybody any ideas where I'm going wrong?

Thanks.

Chris

 

[runnach]

You will always get some amount of pickup on the tungsten using scratch start. Does your set have "lift up" capacity?

Regarding "arc cutting out" reads to me you are allowing the arc length to get too long, to far from work piece, arc ceases. Try to maintain a max distance of 5mm, hopefully this should help, perhaps another member with scratch start experience can offer further advice?

Cheers.

 

[dstealth]

You will always get some amount of pickup on the tungsten using scratch start. Does your set have "lift up" capacity?

Regarding "arc cutting out" reads to me you are allowing the arc length to get too long, to far from work piece, arc ceases. Try to maintain a max distance of 5mm, hopefully this should help, perhaps another member with scratch start experience can offer further advice?

Cheers.

Thanks for the advice. I'm not aware that my set has lift up capacity. I don't think it does. I think you may be partially right about why arc is cutting out. When I'm using the filler rod, my hand is a lot more unstable than when I'm just using the torch itself and running it along the workpiece. Therefore the distance between the end of the tungsten and the workpiece is constantly varying compared to when I have two hands on the torch, hence its reason for cutting out.

However, sometimes the arc doesn't even last for a second once I've 'scratched' the tungsten over the metal -it just cuts out straight away so I have to do it several times?! This is clean metal I'm working with as well!

Also, is there any preferred position to hold the torch in your hand? I looked on Miller's site and it says to strike the arc at 90 degrees to the surface of the metal and then tilt it back to 70 degrees to do your weld and hold the filler rod at 15-20 degrees to the metal surface. Is that what most people do?

Oh and that's my third and final disposable bottle of argon used up. Definitely going to Energas on friday to pick up a biggin.

On that subject, what type of regulator would be most suitable for the big bottles - a standard two dial one or one of those fancy flowmeters?

Any advice greatly appreciated.

Chris.

 

[malcolm]

How are you sharpening your tungstens? Grinding them radially is supposed to give a stray arc. Grinding them axially is the way forward. That's with the tungston held inline with the grinding wheel rather than coming in from the side.

I have terrible trouble with stray arcs after I dip the end in the weld pool (which I'm not supposed to do ). Big molten blob of steel forms on the end and does no good at all to arc stability. Though regrinding sorts it out.

Scratch start is an accepted technique so I doubt it's the cause of the trouble. I wonder if your trouble was the disposable bottles. TIG seems to eat argon and the regulators on the disposables are famous for not supplying enough gas even for MIG. Energas will be a good way forward either way.

I run 2 dial regs. But I guess the fancy ones will give a more accurate flow reading.

 

[dstealth]

Hi Malcolm,

I always sharpen my tungstens axially so this cannot be the problem, however I do use a grinding wheel which has been used for other things in the past, which I've heard isn't meant to be good practice as it can contaminate them. Could this be the problem?

As far as the disposable bottles go, I'm always getting a nice healthy 'sshh' sound of gas coming out of the torch which would indicate that enough gas is being supplied? And I've never had any trouble getting decent welds with them when I've used them on my MIG in the past!?

When I've got the big bottle from energas hooked up to a proper regulator and have the correct flow rate set, I'll post back my results/findings.

Thanks to all for the help so far.

Chris.

 

[TonyWilk]

...However, sometimes the arc doesn't even last for a second once I've 'scratched' the tungsten over the metal -it just cuts out straight away so I have to do it several times?! This is clean metal I'm working with as well!

I have HF start, but have had a problem with the arc running off and going out - the metal was 'clean', after grinding, but I eventually sussed it was a bit oily (WD40 actually).

...Also, is there any preferred position to hold the torch in your hand? I looked on Miller's site and it says to strike the arc at 90 degrees to the surface of the metal and then tilt it back to 70 degrees to do your weld and hold the filler rod at 15-20 degrees to the metal surface. Is that what most people do?

Sounds about right - one problem is moving the tip out of the way slightly to dip the filler rod in the weld (rather than sticking it to the tungsten ), try moving off to one side a bit rather than 'up and away', which can lose the arc.

With HF start I find it easier to lay the torch back, resting on the ceramic to prevent wobbling and dipping the end in the metal. I've not used scratch-start, but maybe angling the torch away rather than lifting it away might be more controllable ?

When showing a MIG-welder friend of mine, he seemed almost allergic to touching the 'shroud' on the workpiece - with TIG, as long as you're not heavy-handed, it's handy to tilt the torch and rest on the ceramic momentarily when, for example, fumbling for more filler

Especially on low current it's easy to wiggle away for a fraction of a second and lose the arc; if you keep the tip short and angled back, you can err on the 'keep close' side and touch the ceramic without dipping the tip.

... I hope that makes sense


Yours,
Tony Wilk

 

[dstealth]

one problem is moving the tip out of the way slightly to dip the filler rod in the weld (rather than sticking it to the tungsten ), try moving off to one side a bit rather than 'up and away', which can lose the arc.

That's a good tip. I think I have been lifting it up to try and get the filler rod in - obviously this would cause arc problems!

with TIG, as long as you're not heavy-handed, it's handy to tilt the torch and rest on the ceramic momentarily when, for example, fumbling for more filler

Another good tip! I haven't tried resting the torch on the ceramic both when welding normally to stop wobbling and trying to fumble for more filler! I hadn't yet worked out how I would get more filer when I needed it, but your method sounds like sound advice.

Cheers

Chris.

 

[runnach]

Hi Chris,

I'm just curious as to how you hold the torch? Myself welding down hand, I hold the torch similar as you would hold a pen while writing, with this method you should be able to steady your hand by lightly resting part of wrist on weld bench, in fact, lightly resting where possible on what ever you are welding. Fillet welds, I hold torch pistol grip style, for a learner this method does tend to allow for arc wander. Whatever style you use, try to be as comfortable as possible!! Back to down hand, there should be no need to move torch to accommodate you introducing filler wire, with correct tungsten stick out, correct arc length, torch at 70 degree, filler wire held at approx 20 degree (giving a 90 degree inclusive angle) Assuming you are right handed, keep your head and body more to your left, taking this approx stance should give you very clear vision and, allow you full control of the task in hand.

As for weld regulator, 2 stage is suffice, but by all means, go for one with flow gauge if you wish. From one of your previous replies above, you state you clearly hear "Sssssh" sound of gas flowing from torch. Too much gas causes turbulence, thus dragging in the outside atmosphere into the gas shielded area causing contamination. Too little gas pressure, again outside atmosphere pushes in with same result of contamination.

HTH?

 

[dstealth]

Hi Runnach,

Thanks for the constructive and helpful reply. Below are photos of my TIG torch and the first one with my thumb over the trigger is showing you how I usually hold it when welding. Looking at other torches, this seems a very odd style, non-standard looking torch as most TIG torch handles are usually long and thin, presumably so you can grip them? Anyway, here are the pics:-

Thanks for the info on the regulators. I should be getting a big bottle of gas on Friday so I will get an argon reg and also opt for a flowmeter whilst I'm there. My TIG like my MIG only has the small thin gas pipe that you see on hobby welders so I'll be needing another one of those adapters to suit the bigger bottles like I have on my MIG.

Chris.

 

[TonyWilk]

Have a look at this earlier post about holding the torch.

...problem with those pictures is they assume you are using a footswitch - having to click the trigger does limit your options a bit


Yours,
Tony Wilk

 

[dstealth]

problem with those pictures is they assume you are using a footswitch - having to click the trigger does limit your options a bit

Hi Tony,

Yes, you are right, the pictures from Miller's site do assume you are using a foot pedal and the TIG torches in those pics are what I would call the normal, standard looking type unlike mine which is pretty unique and has the gas trigger incorporated into the torch!

I'll just have to keep on practicing with it and see if I get the hang of it. If not, I might look into seeing wheter if its possible to retrofit a standard torch onto my machine!

Chris.

 

[Wozzaaah]

Hi Runnach,

Thanks for the constructive and helpful reply. Below are photos of my TIG torch and the first one with my thumb over the trigger is showing you how I usually hold it when welding. Looking at other torches, this seems a very odd style, non-standard looking torch as most TIG torch handles are usually long and thin, presumably so you can grip them? Anyway, here are the pics:-

Thanks for the info on the regulators. I should be getting a big bottle of gas on Friday so I will get an argon reg and also opt for a flowmeter whilst I'm there. My TIG like my MIG only has the small thin gas pipe that you see on hobby welders so I'll be needing another one of those adapters to suit the bigger bottles like I have on my MIG.

Chris.

That torch uses the same body and gas valve as the small cebora migs which is why it looks odd, check out this pic from another post on the forum.

It may be that someone has turned the torch head round as it suited them better or it may be that they're meant to be used that way. It looks quite a big clumsy arrangement anyway, I'm sure you'd be able to retro fit a valved torch to it somehow, If it's scratch start only then the trigger should only operate the gas valve so replacing the torch to a smaller one might be fairly straightforward.

 

[dstealth]

Hi Wozzaaah,

I know its the same as the Snap-On/Cebora MIG torch as I have that MIG welder as well. They're also both in identical casings as well, except the TIG says Cebora on the side and the MIG says Snap-On.

You're right, it is a clumsy torch to use for TIG (fine on the MIG though) and also quite heavy as well. Thanks for the reassurance that it may be fairly straightforward to fit a different torch. I think I may end up going down that route.

Chris.

 

[matt1978]

The problem most people have with tig when first starting out is maintaining a steady arc.

Thats why for a hour or so, all you should do is practise striking up and running the arc down some scrap plate a few dozen times. Both hands on the torch, not worrying about filler wire, once you can do this consistently try it with one hand. Only when you can do this should you start adding filler wire or you'll forever be hit and miss.

Your Tungsten should be ground as Malcolm pointed out with the lines on the Tungsten running North-South, this helps maintain a stable arc especially at low amps.

As soon as you touch down or get a blob of metal on the Tungsten, you should stop, re-grind the tungsten and start again. With tig, especially at low amps you need to focus the arc very accurately and you will only do this with a sharp tungsten.

You should only have about 8 Lpm gas rate too, so if you can hear a whosh or it sounds the same as mig then maybe you need to turn the gas down a bit, too much gas can be worse than not having enough.

Unfortunately its just down to practice, as you have probably realised by now, its much harder to get the hang of and much less forgiving than mig or mma welding

 

[runnach]

Hi Chris,

Torch looks like something you purchase from an Anne Summers catalogue I would imagine you will improve leaps and bounds with a replacement, ergonomic, run of the mill standard TIG torch!!!

 

[weldequip]

Chris,
The torch you have is the original, Cebora TIG torch for that model & probably the cause of your 'problems'. It is indeed a modified version of the MIG torch used on the "Pocket MIG", but original & not 'botched'. Apart from it being relatively bulky to hold, you also have to press hard on the trigger to get any gas flow... TIG is a delicate process & by the time you have scratched the arc your finger is going blue! and all is lost.
The Pocket MIG was the first on the market & a tremendous success... they were probably just following it up with one of the first home user TIGs, but that torch is a bloody nightmare to use & there is no retro-fit to my knowledge.
weldequip

 

[dstealth]

there is no retro-fit to my knowledge.

Thanks for the reply steve.

Then by that I'm assuming that you're saying that these torches use a non-standard fitting that is unique to these machines?

I'll open the casing up and take a photo of the end that goes into the welder and maybe then you can tell me if a standard replacement is available.

The torches on the MIG version works fine as I have one of these as well (as you already know). That steel liner I got from you is now fitted as well

Chris.

 

[weldequip]

Then by that I'm assuming that you're saying that these torches use a non-standard fitting that is unique to these machines?

Yep. It would probably be possible to convert it to a 'standard' torch but that would involve a fair amount of messing.
weldequip