- Thread starter dazza
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choco
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The stahlwerk works without doing it but it starts better when you do it. A freshly ground tungsten you don't, your only removing the surface of the tungsten as in wiping it across the metal, iv seen a lot of people doing this also, it just gives a more stable arc when starting , the next time the op has a problem starting with the HF, do nothing else but lightly scrap the tungsten across a bit a metal and see does it start then
Richard.
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Gold and white are both nice on AC. Grey work ok they are not quite as good IMO but more noticeable on dc. Personally I don't think you need worry too much. Just get what's available.
Brad93
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Turn your amps down to 120 and see if the tungsten holds up a bit better.
HughF
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The rectus 21 fitting you have is likely not a nut/tail style so will always leak when fitted to the gas input. Ptfe won't work because the threads are straight, not tapered. Liquid thread seal or threadlock will sort it out.
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Richard.
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I do this when using scratch start
The filler is in contact with the job and I flick the tungsten off the filler to start up. This way the tungsten doesn't accidentally stick and cause inclusions on the job.
dazza
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I will give that a try.
Don't even feel like taking pictures of todays efforts
.They only had green, grey and red tungstens so i got the grey.
Once i get started things are much easier than before if i loose the arc length it splutters a bit and i can tuck it back in and carry on, with the thinner tungsten it would ball.
But still cant get her to start.
Freshly prepped tungsten will start fine.
Scratching sometimes works.
Using the hot start will work but it leaves a nice ring of soot.
slim_boy_fat
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I stumbled across this method by accident and use it whenever I'm practising now [when it isn't too cold to be out in the shed
]
Richard.
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Swap torches daz. Rule it out.I will give that a try.
Don't even feel like taking pictures of todays efforts
They only had green, grey and red tungstens so i got the grey.
Once i get started things are much easier than before if i loose the arc length it splutters a bit and i can tuck it back in and carry on, with the thinner tungsten it would ball.
But still cant get her to start.
Freshly prepped tungsten will start fine.
Scratching sometimes works.
Using the hot start will work but it leaves a nice ring of soot.
dazza
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brockenhammer
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Hi all,
I was a little curious how the AC behavier of my old EWM was, so I made some testing today.
Here are the results:
I had the biggest problems with the start of the weld. Not the HF ignition (hotstart was at 2), but creating a nice shiny puddle. That took some time and I have to leave the arc on some point in the beginning to let the cleaning action doing the job at first. I don´t know how to do that on very thin material. I think that it would melt away..
If there is a shiny puddle, than going forward is not a problem.
My 2.4 elektrodes are to small for something like 150A AC the ball is around 3mm diameter.
I will have to try 3.2 (blue or gold)
I realized differences when I changed the settings on the machine, but to be honest, I don´t know which to prefer.
125hz and the balance around the middle works o.k. for me.
When the preparation of the material was not o.k. then I had bad problems with horrible uneven and contaminated welds. I had to clean also the innerside of the profile I used.
Anyway the results are not that clean, the surface is not very even and shiny. Maybe more cleaning or different material? What do the pro´s say?
regarding the torch Darren: I had one that drove me crazy. It was a small (size9) torch and I had to weld some bigger material but was to lazy to change the torch. When it became to hot I put it into a pot of water (great idea, I know). After that I had big problems with corrosion/contamination during the welding process. I changed all the small parts, the gas bottle and the pressure regulator without success and at the end the torch body.
Kai
I was a little curious how the AC behavier of my old EWM was, so I made some testing today.
Here are the results:
I had the biggest problems with the start of the weld. Not the HF ignition (hotstart was at 2), but creating a nice shiny puddle. That took some time and I have to leave the arc on some point in the beginning to let the cleaning action doing the job at first. I don´t know how to do that on very thin material. I think that it would melt away..
If there is a shiny puddle, than going forward is not a problem.
My 2.4 elektrodes are to small for something like 150A AC the ball is around 3mm diameter.
I will have to try 3.2 (blue or gold)
I realized differences when I changed the settings on the machine, but to be honest, I don´t know which to prefer.
125hz and the balance around the middle works o.k. for me.
When the preparation of the material was not o.k. then I had bad problems with horrible uneven and contaminated welds. I had to clean also the innerside of the profile I used.
Anyway the results are not that clean, the surface is not very even and shiny. Maybe more cleaning or different material? What do the pro´s say?
regarding the torch Darren: I had one that drove me crazy. It was a small (size9) torch and I had to weld some bigger material but was to lazy to change the torch. When it became to hot I put it into a pot of water (great idea, I know). After that I had big problems with corrosion/contamination during the welding process. I changed all the small parts, the gas bottle and the pressure regulator without success and at the end the torch body.
Kai
dazza
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Thanks for taking the time to do some testing Kai, much appreciated.
With the hot start did it create any soot? How was the tungsten prepped?
I will try the same settings later and see what happens.
On my initial testing the other day i did notice i would get a better start with a higher HZ but today it was around 80-90.
Here were my efforts from earlier lost my temper in the end and tried to spark up everywhere
.
Happy with the pedal is seems a solid piece of kit
With the hot start did it create any soot? How was the tungsten prepped?
I will try the same settings later and see what happens.
On my initial testing the other day i did notice i would get a better start with a higher HZ but today it was around 80-90.
Here were my efforts from earlier lost my temper in the end and tried to spark up everywhere
.Happy with the pedal is seems a solid piece of kit
Richard.
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Hi Kai.
There is no reason to use a 3.2 electrode on current levels below 200 amps AC. I don't even own such sizes and aluminium is 90% my welding world.
Your AC balance at somewhere in the middle I can only assume is a balanced wave (50/50) which is why your getting the big ball.
Contamination can be caused by loads of things with Alu and changing the cleaning cycle to try take it out more often than not has no effect.
I'm not one for scrubbing the parent to death unless it's really needed but I religiously wipe every bit of filler rod down with a drop of solvent on a rag and this makes a hell of a difference you would be surprised.
I also wipe my stock down too. Little tiny things like dust and finger prints can play havoc with the arc and it can be the difference between clean and scabby.
If you insist on scrubbing it like many people do be sure to give it a good wipe afterwards with solvent as what you have scrubbed off will be sitting there ready to cause you problems. Personally a rag and acetone is all I ever need to produce clean runs.
The fillet and lap joint below were performed on really thick 6mm Alu
205 amps with a 2.4 tungsten.
No scrubbing just wipe and weld.
Richard.
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This gets a lot of people when they first start out with Alu and it's the nature of the beast.
Aluminium has huge conductivity properties
Aluminium has an oxide layer that melts at 1800 degC.
Both of these equate to lots of start up current to punch through that oxide layer and heat soak the part.
If your waiting around for any more than a couple seconds before you can feed fill then your current is too low and it's likely you will burn the edges away on thin stuff.
You need to hit the thin stuff quite hard and get a pool instantly get fill straight in and get straight off the gas. This is now tacked. Once you have a tack your laughing because you now have solid ground to start a run. It takes some practice but don't tickle it with 20 amps on a pedal. This will result in loosing material. I turn all slopes off when tacking on thin sheet.
Richard.
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Daz I don't know what that switch does but it's there on the machine ready to be switched about. Don't be frightened to change stuff it (shouldn't) blow up.Just been looking at the manual again. Whats the variable ignition current (search arc)?? Should this be on 0%?
Its the first button on the left after the button for the pedal/switch.
