New 250P problems

[balleman3]

1.25 x 1/8 aluminum, everything was tig welded with my new 256 @ 240A and I’m starting to wonder where the duty cycle is I cant seem to find it LOL... really never hit it, all I ever did was wait on the duty cycle on my 300lb Lincoln precision tig 225 the old fat girl just sits in the corner these days just watching the the little green machine work...

[zoama]

Nice work. What are the dimensions and weight of this awning and how big is the boat ?

[sportbike]

I'm going to guess a tick over 800lbs finished weight, depending on how much scrap was made with the cuts.

Were you really using 240 amps to weld this or was the machine just set on 240A?
Pedal or torch switch?

[balleman3]

240A maxed out start tapering off the amps right at the end, I did all the welding at night when it was cool. its around 700lbs of tubing but is built in 2 pieces its split in the center. catamaran is 50ft long 30ft wide, I did the handrail on it to. I always used a pedal until I picked up this rotary now I never use a pedal

[Rambozo]

...its around 700lbs of tubing...

Plus how many pounds of filler rod

Thanks for showing just what the 256 can really do. I have been undecided between the 250EX and the 256, and seeing things like this really helps.

[balleman3]

10lbs+ 3/32 4043, 1lb 1/8

[balleman3]

yea the only hold up is the amperage limitations of a 1/8 size tungsten

[zoama]

yea the only hold up is the amperage limitations of a 1/8 size tungsten

Have you tried 2% lanthanated ?

[balleman3]

I read somewhere 1%zirconaited holds up best on hi amperge AC so I ordered a 10 pack but I will try out the lanthanated thanks

[sportbike]

I'm still amazed that you were welding with 240A for that many welds. Must be able to move really quickly with that much current.

I don;t think I have ever heard of any duty rated machine that doesn't shut off or throw some sort of thermal limit indication causing an issue, especially if the air is not even warm. If that is the case, it is pretty shady "engineering".

If the weld current was tapered down, it very well could be that 35% @ 250A wasn't exceeded since the welds are all pretty short.

[performance]

Most of the time it will, and perhaps, conditions were just right when he was using it. But true duty cycle is figured at 40 degrees Celsius. And heat dissapation rates are affected by the temperature, and humidity. But the heat must transfer from the IGBT to the aluminum. The heat transfers out of the aluminum faster than it does from the igbt, so theoretically, the igbt and other components could still be hotter than it should and the exact position of the heat detector may stay cooler, since it is away from the other end somewhat. At this point I am postulating why the thermal would not trip. But when it comes to inverters, constantly running a unit against its duty cycle is not recommended because of the cumulative damage/wear done to the electronics. A transformer can be run up to the duty cycle, and other than melting out some solder, little is there that can break...so the effect is not as bad.

[balleman3]

yea as soon as it started to puddle i was on the move fast and I’m used to tiging as fast as the power I have on tap will let me, done a lot of aluminum in the past. sometimes after running for awhile it seemed like the amperage would start to drop off on its own toward the end of the weld I thought it was my imagination but now I think I was overdoing it, I just figured it would cut itself off if I hit the duty cycle like my transformer unit. I only welded one flat at a time so most of the amperage was expended on getting thing up to temp the air temp was in the 60's and machine was outside
on a side note
is my 250p supposed to have a - symbol in front of the amperage display the lcd shows -250 is that correct? could the plug be wired wrong, It is not welding good at all, like the polarity is wrong, same with the spoolgun

[zoama]

is my 250p supposed to have a - symbol in front of the amperage display the lcd shows -250 is that correct?

Mine does the same.

[performance]

yea as soon as it started to puddle i was on the move fast and I’m used to tiging as fast as the power I have on tap will let me, done a lot of aluminum in the past. sometimes after running for awhile it seemed like the amperage would start to drop off on its own toward the end of the weld I thought it was my imagination but now I think I was overdoing it, I just figured it would cut itself off if I hit the duty cycle like my transformer unit. I only welded one flat at a time so most of the amperage was expended on getting thing up to temp the air temp was in the 60's and machine was outside
on a side note
is my 250p supposed to have a - symbol in front of the amperage display the lcd shows -250 is that correct? could the plug be wired wrong, It is not welding good at all, like the polarity is wrong, same with the spoolgun

No that shows it is reading relative wire speed. It will change to amps once it starts to weld.

Are you using pulse? Don't until you know how to set up the MIG without it.
What wire diameter are you using? Do you have the work clamp in the negative, or rather, work? Which groove are you using on the drive roll? What wire type, gas type, and gas flow rate are you using?

[balleman3]

clamp in (work) - pulse seems to help on flat surfaces but no not using it now trying to get it to weld proper without first. tried

Steel %75ar-%25co2 .035 1/8-1/2 in thickness all kinds of combinations of V and amperage always starting with the recommended settings and slowly moved around from there.

Aluminum %100 ar spoolgun .8mm wire .090-1/4 in thickness all kinds of settings and thicknesses always starting with recommended, same result piles up on the surface or jumps to spray arc and melts to a ball 1/4 away from work and flows with gravity from there only looks good on flat steel cant really put it where you want it
I have worked as a mig welder in the past so I have experience adjusting mig machines, also used to build aluminum awnings for another company using a spool gun everyday
I still have to put the tie bar in for the awning caves I really dont want to have to tig weld the 125ft of 3/4 by .090 aluminum square tubing thats what I bought the mig for
is there any way to adjust the wire speed without messing with the amps?

[Rambozo]

Is there a possibility that the duty cycle heat sensor is faulty?

[balleman3]

my new 250P actually I think it was a demo model looks well used more than just testing but I wasn’t to concerned about that. I thought I had a gas flow problem but now I think I have eliminated that it is even worse with the spool gun and straight argon when I turn the gas up to 50CFH hold the trigger down and plug off the gas at the spool gun it comes squealing out around my finger and no where else inside the machine or any connections seem to be leaking under pressure, I know my argon is good I can make beautiful tig welds with it. >>Arc force, wire speed and CFH<<< make no difference in the terrible black soot with the spool gun it just gets worse with higher gas flow rates, 25CFH is what I ran on the one pic, all aluminum is new, cleaned, brushed and wiped with alcohol, the aluminum pic is 3/4 by 1/16. steel welds are terrible to regardless of settings 75%-25%co2. please don’t ask what the arc force, wire speed, or voltage was set on I tried all settings independent of one another and this is as good as it gets. the only thing It will do any good at is very high voltage pulse spray arc on very flat steel.
I also have to cycle the power on the machine constantly because the arc dose not start when the wire makes contact, Its the same ground cable-clamp I use on my tig with no problems

[Rambozo]

Can you try it with the gas down around 12-15 CFH. It really looks like there is some kind of shielding problem. Granted you may also have an electrical fault, but black soot only happens when there is oxygen present around the weld. Even if the machine is putting out some crazy wave form that will never weld, you shouldn't be getting the soot. That just isn't caused by the electrical properties of the arc. The other symptoms may very well be a problem with the machine, but you need to isolate things one step at a time. If you have a volt meter you might want to double check the machine polarity. Make sure the torch is really positive, forget what the labels say and measure it. At the same time you can verify that the voltage matches the display. Is the wirefeed displayed about right? Hit the button for 10 seconds, without welding, and measure how much wire comes out. Someone from tech support can walk you through opening it up and checking the main connections inside the machine, if you want. Does it act like the power is weak or cutting in and out? There just really isn't all that much happening in a MIG power source. It's basically plain old DC. As long as the voltage and polarity are correct it should weld. If you can post a video, it might help, even if it's just the sound.

[performance]

Posting multiple places will not help this, and only dilute the information.
As I told you on the other thread, IF you are making contact with the metal with the wire or the cup when you start the arc, you will create an overcurrent and shut down the welder.

[JimMinKent]

Run the lower gas rate per Rambozo, and Change the direction you are welding. Use Push rather than Pull technique. The gun should be aimed to flow gas over the area you are about to weld, not the area you just welded. You will still get some soot with AL mig, along the sides beyond the bead, it's part of the process, it is not clean like TIG, but pushing the gun will clean up your welding about 90%+.

Also,for Every start, cut the wire back to the tip, this does two things. First it provides a nice sharp edge to begin the arc, but more importantly, it gives a moment of pre-flow, which is needed to create an environment that can support the arc. Some of your examples show that there was no shielding when the arc was initiated.

Don't mess with pulse yet, soon maybe, but get the hang of it in short-circuit transfer mode. Pulse mig is really for one purpose, to provide a faster freeze for out of position AL Spray transfer mode. In that mode you are running really hot, big puddle, and without pulse, religated to flat position welding.

Change direction, Have Fun, and take more pictures!

Jim