[Fly]

I all most never use my pulse when welding. Ole school guy I guess. But I,m planning on playing
around with it. What % do you recommend upping the amps on steel & on aluminum ?

Fly

[Oscar]

It all depends how you set up the pulser. It's possible that you set it up in such a way that you need to set the main welding amperage twice as high, or it can be set up in such a way that you don't need more than 5% more. With pulse frequency, pulse duty cycle, and base current, there are three degrees of freedom allowing for many, many possible combinations. I would start with around 50% more amperage if using "typical" settings.

[rick9345]

Oscar
if using "typical" settings.

And just what are typical settings

[cj737]

I would differ from Oscar's approach in that usually when you pulse, you're trying to control heat input. Cranking up the amps would necessitate cutting the peak time down severely, and relying on background amps to keep the metal from shocking. Certainly you might need to bump your amps, but I would use a range consistent with short bursts, not flash tacks.

I use 1.4 pps, 25% peak, and 50% background and find it to be very productive and easy to work with. The tempo of the pulse is almost bloody perfect for a metronome like pace of dab and move. But, everything is variable with pulse. You just gotta experiment lots. And when you do, experiment with cold pieces as you adjust your settings to know accurate effects.

[Otto Nobedder]

To date, I've only used pulse on aluminum, and fairly heavy sections (3" sch. 10 pipe with backing ring, 6061T-6). I always set the machine wide open for aluminum and modulate with the foot pedal, so I can't really tell you a peak amp difference. Like CJ, I like a low pulse rate. I was partial to 2PPS and would let it pulse once before I dab and advance. This made a nice steady rhythm, and gave the first pulse the time to establish the front edge of the puddle before the dab at the next pulse. I found Jody's "rule of thirds" got me in the ballpark, i.e. 33% background and 33% peak time. I also found that 120 Hz gave me better arc and puddle control, if you have adjustable frequency.

I take back the first thing about heavy sections. I also used this on 3/8" .049 wall instrument tube, also 6061, and socket-welds to big fat couplers they had (badly) machined. In this case, I had peak amps at 110, rather than WFO, and it was all about heat control so I didn't collapse the .049 while welding to a friggin' slab of a coupler. Frequency was maxed at a very irritating 400 Hz.

My two cents.

Steve S

[cj737]

Frequency was maxed at a very irritating 400 Hz.

Ouch! My buddy who just bought a new 280DX was tinkering with the machine at 500Hz. Frickin' drove me out of the shop , down the driveway and around the corner. And my ears still hurt! I would love to see the Machine companies find a way to suppress that noise output as they have done with their fans. I've used molded ear plugs when welding on mine at 200Hz for extended periods, but dislike not being able to hear "environmental sounds" that might be indications of danger...

[exnailpounder]

If you want to be driven into an epileptic seizure...try welding at 10 pps

[Otto Nobedder]

Frequency was maxed at a very irritating 400 Hz.

Ouch! My buddy who just bought a new 280DX was tinkering with the machine at 500Hz. Frickin' drove me out of the shop , down the driveway and around the corner. And my ears still hurt! I would love to see the Machine companies find a way to suppress that noise output as they have done with their fans. I've used molded ear plugs when welding on mine at 200Hz for extended periods, but dislike not being able to hear "environmental sounds" that might be indications of danger...

One of my co-workers listens to his i-pod all day, and has noise-cancelling earbuds. It works great for him, and irritates the hell out of me. I'll speak to him, then wait for him to lower the volume, then repeat what I just said. I'd think noise-cancelling technology would be the way to go at higher frequencies.

Steve S