- Thread starter Dave Llew
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Thats great, dont know where I got 2000Hz from then
I'm having trouble finding the used equipment section, Appyasme posted a kemppi on, any idea where I find the used equipment?
Thanks
Richard.
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You won't get 0.5 hz either. I think your referring to pulse not ac freq. pulse welding is totally different and usually only performed in dc. My Fronius has a massive scope of 0.1-2000. Don't confuse the two as they are very different. Pulse is 2 current settings ac freq is 2 different polaritys.
Paul.
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Click the forum button at the top of the page, all the different sections can then be found in the list there
I must be
In that case, which pulse range is most useful? The guy in either Thermal arc or Parweld technical, I cant remember which, said I could use pulse on both AC and DC, how does that work if your already using a frequency close to the pulse you want, couldn't that mess it all up, does it just literaly switch on and off, cutting out a section of wave, or is it set to cut on and off, just delaying the wave, or have I completely crossed wires there somewhere too?
Thanks Paul
Richard.
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Ok this ismy opinion and others may disagree. Pulse on ac is the same as on dc. It bounces between 2 current settings ac freq is different and there is no link between the two things going on. Pulse on ac is pointless. I can do it with mine but never found a use or reason to do so. Pulse on dc for me serves one purpose. Heat input reduction. I use it at high hz (100 min) on thin gage long continuous runs usually stainless where I need to control distortion. I see people using slow pulse to enhance the freeze frames on Tig purely For the stack of dimes effect. I can do that without a pulse so I use high hz to tighten and concentrate the arc.
Tinbasherdan
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Anywhere from 1.2 ally up to 8-10mm
I use pulse instead of a pedal....
Richard.
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Pulse and pedal don't offer the same advantages. One offers variable current control On the fly the other offers reduced heat input over a high and low current setting. Not the same thing at all.
Tinbasherdan
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Yes mr shiney but what Richard is saying is that it's not a replacement for the pedal at all, pulse and a pedal both are very different things and have specific uses
I know exactly what Richard is saying. He is a talented perfectionist. The rest of us are bodgers and get the job done. I very successfully use pulse mode to control heat on jobs as I don't have a pedal or space to use it. There are many ways to skin a cat as they say!!
Richard.
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Pulse does control heat input mr shiny so there is no arguement there. It's not essential to use on Alu for two reasons.
1 you travel fast with Alu tig any how because of it's nature and low melting point.
2 Alu has high thermal conductivity and localised heat spreads quick making distortion less of an issue
The two reasons above are where a pulse would come into shine.
A pedal gives you power like a car throttle. Alu has two melting points 1800 and 600.
The oxide layer is around 1800 and when the Alu is cold you need to stamp on the current to get it broken through. Once through the Alu itsself (600) is molten and gonna run away quick. You then back off the pedal to a manageable current so you can feed filler at a sensible rate. So it just makes it easy. As you know you can weld it with out a pedal I do that quite a lot when I can't sit at the bench. All I was saying is a pulse doesn't offer a replacement to a pedal. Nothing to do with perfectionism just stating a point.
Richard.
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Also mate I need to make a point. I've seen some of the pictures of jobs you've done and they are hard jobs performed to a good standard. I was particularly impressed with the head fin you did. So saying you've not got talent at welding is daft. I've never welded a head fin back on I've always built them up from scratch and shaped them back so that for me was talent. Just because we don't agree on technique etc doesn't make me any better than you at the torch end.
Gavin Melville
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I've got a Kemppi 2300, and couldn't be happier with it. You do need the ACX front panel, and I found a foot pedal necessary for Aluminium.
The only negative is some days I get really crappy looking welds. Sooty, no penetration, munted tungsten.... If I cut it out and do it again it is always ok. So far I'm blaming the machine.
The only negative is some days I get really crappy looking welds. Sooty, no penetration, munted tungsten.... If I cut it out and do it again it is always ok. So far I'm blaming the machine.
Richard.
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Black soot and dulling of the tungsten is down to oxides been transferred across the arc.I've got a Kemppi 2300, and couldn't be happier with it. You do need the ACX front panel, and I found a foot pedal necessary for Aluminium.
The only negative is some days I get really crappy looking welds. Sooty, no penetration, munted tungsten.... If I cut it out and do it again it is always ok. So far I'm blaming the machine.
Insufficient gas coverage is the reason but it's rarely because of flow rates. Usually arc length is the cause. If you know your arc is consistently short then look for things like a gas leak. Quite often I hear of the first bead been awful and sooty then the next ones clean up. This is usually a gas leak on the torch itself and as the torch gets hot, expansion of the fitting can seal the leak. Try these things first as I doubt very much it's a fault with the machine.
