Pulse help with TIG

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I'm not sure I understand what "pulse" is on my TIG so I'm looking for some advice/knowlege.I thought that pulse meant that it will oscillate from your high amperage setting and your low amperage setting. Then I can set set a percentage of time I am at my high setting, and the corresponding time I am at my low setting.Then I can set my frequency and this is where I am confused.My machine goes down as low as 0.5 Hz. It goes up to well over 100 (didn't attempt to turn it up that far)My understand of pulse (from assumption only) is that the machine will go from high to low and I dip my filler when the machine is on my higher amperage setting.But I can only do that at my lowest frequency setting. Anything higher, even 1.0 is way too fast for me. Can someone correct my thinking? I know I am wayyy off about something here.I tried pulsing at 100hz and i couldn't even tell the difference between high and low amperage it went so quick.Also: Is pulsing only for square wave?I have 3 different wave form settings on my machine and I have always been welding with square and nothing else.
Reply:Well, at a .5 hertz you might get away with a dip on the hot side of the pulse, but what it really does is balances out heat.  It really meant for thinner materials to allow you control puddle size and keep you from burning through (with aluminum it helps to keep the heat from spreading to quickly through the material).  I played around with the pulse feature quite a bit and for what Ive been welding determined it was just getting in the way (1/4 inch, 3/16, 5/8 that kinda thing).  Higher Frequency on ac tightens the arc (makes a smaller weld puddle at the focus).  The stuff you showed in your previous post would benefit from pulsing.  It wont clean up your contamination, but will help you control heat better.  Try running it at say 50 hz.  It makes a hell of a buzz, but I think youll see what I mean.  Get some scrap and weld with no pulse, try and burn through, then do the same thing with the pulse on.Various GrindersVictor Journeyman torch200cf Acet. 250cf oxygenLincoln 175 plus/alpha2 gunLincoln v205t tigLincoln 350mpEsab 650 plasmaWhen you can get up in the morning, Its a good day.Live each day like its your last.
Reply:Well done!     Your description of the pulse settings was completely right on the money.   Sounds like your power supply has settings for peak current (Ipk), background current (Ibk), % time at peak (%Tpk), and frequency (f) in pulses per second.So you set the % time at peak, and the background time is a function of how fast you pulse, the frequency.  The actual time at peak (Tpk) and background (Tbk) are determined as follows:The pulse period (P) is the time for 1 complete cycle = Tpk + Tbk = 1/f seconds.Tpk = %Tpk x PTbk = P - TpkYep, low frequency pulsing is slow enough to make overlapping spot welds, and allow you to dip your wire in sequence with Ipk.High frequency pulsing is not much different than constant current, although people claim it may help "stiffen" the arc.Generally, the pulses need to overlap at least 70% otherwise you can get penetration that varies from deep to shallow because the root of the weld pool is not overlapping enough.Pulsing really helps keep the edges of weld, the toes, nice and straight and even.  Particularly on big/hot welds, with constant current the weld pool will wander around and be uneven and snakey, versus pulse which controls this by the alternating melt/cool cycle.Thin material, less that 1/8", such as stainless steel tubing, can be welded without added filler wire (autogeneous) with a fairly radical pulse, that is a short duration, high current pulse, followed by a long duration, low current pulse, which will produce the overlapping spot welds, keeping the pool small enough and allowing enough pool solidification between pulses to make full 360 degree "orbital" welds (flat, vertical down, overhead, vertical up) with minimal change in weld convexity/concavity on the overbead and underbead.I assume your pulse functions with all three wave forms on your power supply.  I don't see any reason to use anything other than square wave.  Anything other than square is just more gradually sloping the current to its final peak or background, and for very short duration pulses, I believe you need the instantaneous nature of square wave to get actually reach the target setting in time.Generally, a relatively radical pulse will penetrate a given thickness at a lower average current.  If you get full pentration on 1/8" SS with 100 amps constant current, you may get the same weld with a pulsed average current of about 80 amps.For example:  Ipk = 300 amps, Ibk = 10 amps, %Tpk = 25%, f = 3 pps.  Iavg = (Ipk x 25%) + (Ibk x 75%) = (300 x 25%) + (10 x 75%) = 75 + 7.5 = 82.5 average amps.Now this example is a very radical pulse, but surprising that it is not too hot.  The 300 amp pulse is only "on" for 0.083 second.Tpk = %Tpk x P = 25% x 1/3 = 0.083Tbk = 1/3 - 0.083 = 0.25 second Experiment, how much peak time is needed to penetrate or give the weld size you want at a given peak current?Check out this site for a pulse calculator, there are two pages to this.http://www.pro-fusiononline.com/welding/pulseparams.asphttp://www.pro-fusiononline.com/welding/pulserate.aspSorry for the long winded responce, have fun.
Reply:Great info pulser.  Learn something new everyday..Various GrindersVictor Journeyman torch200cf Acet. 250cf oxygenLincoln 175 plus/alpha2 gunLincoln v205t tigLincoln 350mpEsab 650 plasmaWhen you can get up in the morning, Its a good day.Live each day like its your last.
Reply:Wow great info. What I read before is about people "timing their dips" with pulsing but I guess that really doesn't apply.So I've been pulsing completely wrong So I'll try running a high frequency pulse and see what happens. Sounds fun. Thank you guys.
Reply:Originally Posted by UnderwhereWow great info. What I read before is about people "timing their dips" with pulsing but I guess that really doesn't apply.So I've been pulsing completely wrong So I'll try running a high frequency pulse and see what happens. Sounds fun. Thank you guys.
Reply:When I started with the pulse thing, I asked a question here.  Pulser answered.  I tried it and it works great. Some times it helps especially out of position. I use it less now that my skills have improved.  I was teaching my duaghter to Tig steel and told her "one dip per second" this helped her like the pulse helped me.  DavidReal world weldin.  When I grow up I want to be a tig weldor.
Reply:Originally Posted by pulserTiming the dips with the pulse still applies, nothing wrong with that, it works fine if the frequency in slow enough.How have you been doing it wrong, you can pulse slow or fast, it's not wrong depending on what you are trying to accomplish.
Reply:I've heard there are herbs from the Amazon that will help you see the pulses.
Reply:LOL.  You dont dip with the pulses all the time (ok, lets say you dont dip on the hot pulse on anything higher than 1hz?)  What do you think pulser? Various GrindersVictor Journeyman torch200cf Acet. 250cf oxygenLincoln 175 plus/alpha2 gunLincoln v205t tigLincoln 350mpEsab 650 plasmaWhen you can get up in the morning, Its a good day.Live each day like its your last.
Reply:Pretty tough to dip in and out faster than 1 time per second.