WHo uses Pulse on DC?

I started messing with pulse the last few days on a Dynasty 350, I do notice a change in arc, puddle, but can't tell if its honestly helping at all. I've tried a slower pulse with 1-2 pulses a second, 75% on time and the background current at 30%....that was too distracting. If I keep the other setting but turn the PPS to around 60 I notice the puddle seems tighter and less fluid. Is that what they call a hard puddle vs a soft puddle? After a while of messing around I turned it off and loved how fluid the puddle was with no pulse. Can anyone out there tell me an instance where pulsing is really useful? I know it is suppose to cool the metal better...but I haven't started stainless to tell if it is really doing anything that is helping for mild steel other than more buttons and knobs to push. Thanks for the help - RJ

Most of the "features" available on welders aren't really required to get the job done. Most say pulse is useful for welding very thin materials to prevent burn through or edge melting. I know of some who use pulse on AC with aluminum welds, even though his Miller rep was trying to tell him that you don't use pulse on aluminum...he told him that maybe HE didn;t use them, but that his welds didn;t look like this (and showed him some welds). The Miller rep retracted his statement...

I personally have not really seen much use for it, and have welded some thin tubing. I didn't see much help in welding very thin wall chromoly tube either. One of the guys at work uses a standard, hardly any settings straight 60Hz frequency transformer syncrowave and can put most other welders to shame on radiographed aluminum welds for a Navy program we do. (same guy only recently bought an auto darkening helmet).

More features might be nicer, but the fact is that a great welder can outweld a not so great welder any day of the week...great welder with a scratch start old school welder and not so great with every bell and whistle available.

Pulsing is nice whenever you want to reduce the heat you put into a workpiece without sacrificing penetration. Typically to reduce distortion on thin pieces and when welding near an edge that you do not want to melt. Another use for really slow pulsing is to help set your cadence and travel speed. You can also slow pulse manually with the pedal. I've never had a machine capable of the extremely fast DC pulsing, but I understand that this will focus the arc down much like increasing the frequency on AC to pinpoint the heat. Jody has some good example videos of places to use pulse on WT&T. One example was welding down inside a tube where it was hard to see or move the torch smoothly, so you only moved the torch during the background current portions of the pulse cycle. Something I will have to try next time I'm in a tough spot.

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Originally Posted by sportbike

Most of the "features" available on welders aren't really required to get the job done. Most say pulse is useful for welding very thin materials to prevent burn through or edge melting. I know of some who use pulse on AC with aluminum welds, even though his Miller rep was trying to tell him that you don't use pulse on aluminum...he told him that maybe HE didn;t use them, but that his welds didn;t look like this (and showed him some welds). The Miller rep retracted his statement...

I personally have not really seen much use for it, and have welded some thin tubing. I didn't see much help in welding very thin wall chromoly tube either. One of the guys at work uses a standard, hardly any settings straight 60Hz frequency transformer syncrowave and can put most other welders to shame on radiographed aluminum welds for a Navy program we do. (same guy only recently bought an auto darkening helmet).

More features might be nicer, but the fact is that a great welder can outweld a not so great welder any day of the week...great welder with a scratch start old school welder and not so great with every bell and whistle available.

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that's what I was kind of thinking too:) Nice to know all that shtuff is on my new machine if I ever need it but one day I hope to be an old dude with some simple machine that people are talking about:) My instructor keeps putting me to shame with his awesome welds.....almost magic!

I used pulsing (particularly on DC; I am much more hesitant to bother with it on AC applications) when I want to reduce heat input. Occasionally, I specifically avoid using pulsing (such as when I want to increase heat input, in which case I will also weld with a low current and "let the heat soak", such as when trying to prevent medium-carbon steels being welded from hardening. But I will admit I don't do that too often.)

High frequency DC pulsing can also help make the arc "stiffer" and more directional.

One thing rather inconvenient with pulsing, IMO, is you need to do math to figure out how much average current you're welding with. E.g., 100 amps peak, 50% on time, 50% background = 100 * .5 + 50 * .5 = 50 + 25 = 75 average amps... not so convenient to constantly be doing this math to know what you're welding with each time you make an adjustment to one of those parameters. Another inconvenience when using it with heavier materials (or with AC) is that using it reduces the usable power output of your machine. (This is probably more of an issue for a 200 peak amp max output machine than it is for a larger machine.) Because of the inconvenience factors, I will usually only use it when I need it. (But then, it can be a feature that I appreciate.)

I used it the other day to weld fillets between a piece of angle and some 1/8" filler rods without undercutting the rods. Picture a stainless porcupine. It's a sneaky tool you can pull out of your toolbox when you need it, but for straight normal welding I don't use it much. But I have been meaning to try it to see if I can reduce some warping on thinner stuff.

I have used it on A/C to build up a damaged corner on a piece that was ceramic coated without damaging the coating even at the toes of the weld.

Like many things, it's utility depends on the kind of work you do.