Is My Heat Too High

[Gearjam]

I have a Lincoln Powermig 255...and have used It on some heavy duty jobs...I`m sure years ago running 045 wire I didn't have to crank It up as high as now.
To Burn 030 wire I have It set at 485--------22.2voltage
It seems the smaller the wire the more heat I need
I`m a old retired pipe welder who just picked up the MiG when It first came out...so any tips on what this could be will be greatly appreciated

Gears

[lugweld]

Have you changed your gas mix?

That can and will make a difference on your heat settings.

When I changed from 75/25 to a C-18 mix, I had to readjust everything, including the flow meter.

[Gearjam]

No Same Gas Mix....I have 035 In the machine now...and Just tryed It...same thing...for the fun of It I cranked It to 700---------max on voltage...It seemed fairly hot....But never burnt back...for some reason I think maybe this machine got over worked maybe

[Broccoli1]

Originally Posted by Gearjam

I have a Lincoln Powermig 255...and have used It on some heavy duty jobs...I`m sure years ago running 045 wire I didn't have to crank It up as high as now.
To Burn 030 wire I have It set at 485--------22.2voltage
It seems the smaller the wire the more heat I need
I`m a old retired pipe welder who just picked up the MiG when It first came out...so any tips on what this could be will be greatly appreciated

Gears

You have to turn up the Wire speed when using smaller Dia. wire.

example:
1/4" Steel suggested Amperage 180-190
035" (0.9 mm) at 360-380 ipm

.045" (1.1 mm) at 185-195 ipm

[Gearjam]

Ok I see what you meen about the smaller the wire the more wire speed you need

But getting back to me having to crank this machine so high....For 030 wire 485 IP

Plus I`m not getting a nice sound from the arc...I know I have been away from welding for some time now...but there something just not right here

[Gearjam]

I`m useing Argoshield 8-C...gas

[farmersamm]

I don't have this large of a wire machine. So I don't know if this is any good. Sometimes internal wire connections for the torch or the ground can work loose or corrode. It makes a difference.

I had a Lincoln crackerbox die a few years back. It didn't quit welding, but it no longer ran as hot as it had for the maybe 8yrs. I had it. I probably used it a lot more than the previous owner. I bought it at a farm sale. It was a circa 60's machine. I'm sure I exceeded the duty cycle pretty regularly, even to the point of tripping the breaker a few times.

When I bought my new crackerbox, the LWS guy told me that the AC end of the AC/DC crackerbox isn't thermally protected and you have to adhere to the duty cycle by guestimating. I don't know about nicer units like yours.

So anyhow, it might very well be she's been rode hard and put up wet one time too many. It costs a fortune(here anyway) to have them checked. It was around 125 to send my old unit to a place in Tulsa that puts them on a machine that applys load to the circuit under welding conditions. I figured I might as well take the 125 and apply it to the new machine.

It's hard to give up an old machine that's been good to you. Maybe you can have it tested for a reasonable price where you are

Good luck

[Gearjam]

I just checked the conections...they seem ok...Maybe It has been worked too hard, I`m just not getting that Sizzel sound that I`m use to

[farmersamm]

Originally Posted by Gearjam

I just checked the conections...they seem ok...Maybe It has been worked too hard, I`m just not getting that Sizzel sound that I`m use to

I guess it's to the point of having it checked. See if you can get a firm quote on the price for checking it, without repairing it. And ask if the price to check it is applied to the labor to repair it.

If it's like most things nowdays, the price of repair is almost as high as a new machine if it's a major problem.

I recall just about crappin' when I glanced at the price tag on the bigger wire machines like yours.

[lugweld]

An esab 250 migmaster isn't too bad, but anything these days and times cost too much.

[Broccoli1]

Originally Posted by Gearjam

I`m useing Argoshield 8-C...gas

What is the suggested setting on the door chart for the 255?

At least you would know a starting point- although it probably is for c25 & Co2 gas

[Gearjam]

Heres whats n the door settings

[David R]

I have a wirematic 250. The next older unit. Its an awesome machine. Does your fan come on now and then? The windings are part copper, part aluminum.

How does it weld when you set it to the recommended ones?

Maybe recommended setting for C/25 minus one volt because of the C-8.

OR you could sett he wire speed for the middle (350) and adjust the volt knob while welding until you get a good arc and bead.

David

[Gearjam]

Originally Posted by David R

I have a wirematic 250. The next older unit. Its an awesome machine. Does your fan come on now and then? The windings are part copper, part aluminum.

How does it weld when you set it to the recommended ones?

Maybe recommended setting for C/25 minus one volt because of the C-8.

OR you could sett he wire speed for the middle (350) and adjust the volt knob while welding until you get a good arc and bead.

David

Hi David...It welds not too smooth when I set It to the recomended setting(too Cold)

My fan comes on soon as I start welding...hmmmmmmm

I`m not sure how I ended up with 8c gass...and not sure of the difference to the c25

As far as setting the machine...I have sat down with the wire speed at say 320-360...and have one hand on the voltage....seems to pop a bit off the end of the wire

[David R]

What voltage are you at when set at 320 to 360?

David

[MoonRise]

Using 0.030 solid wire, you get a MAX amperage of about 200-210 amps. That wire is approximately 2 ipm/amp in its 'linear' range, which is from about 40 to 120/145 amps. You are way past the linear range, and past the point of exponential current/wire-speed range and into total current saturation of that wire size. The wire can't flow any more current, no matter how fast you crank the wire speed.

If you want more amps/heat than about 200-210 amps, you will have to use a bigger wire than 0.030. And you are probably pushing more volts than needed for short-circuit transfer (globular transfer) and not quite enough for spray transfer.

What do you want to do here, again?

C8 you can go into spray mode transfer or use short-circuit, C25 you really can't get spray transfer (short-circuit or globular only).

[Gearjam]

David...I'm not sure what I had the voltage set to when the ipm was at 320-360...I just sat on the stool with one hand on the voltage dial and the other hand welding....trying to get a good arc.



Moon: Your first sentence makes me believe there's something wrong with the machine

also with the 035 wire...thats In there now..I get the same poor arc characteristics...If I turn It all the way up to max 700IPM with the voltage at max...I'm still able to weld with the 035 wire<------that also tells me there may be something wrong with the machine

What I'm trying to acheive here Is.. getting that sizzeling sound...you know the sound when all Is good?...Thats what I would like this machine to do.

[MoonRise]

The PM255 has enough snot/ooomph/muscle/etc to go waaaay past the "nice sizzle" sound of a nice short-circuit transfer mode weld and into the no-sizzle spray transfer mode weld.

Especially with a tank of C8.

If you keep cranking up the voltage and amperage (wire speed) with that machine, you can and will go past the parameters of a short-circuit transfer weld and into the parameters for spray mode. If you don't go quite that far (especially with the voltage), you end up in globular-mode weld.

Step one, do some PM on the machine. Blow/vac out the wire compartment, check all contact lugs for tightness, check the gun and tip, maybe blow out the liner to clear out crud from there (see the manual for how to do that).

Next, like David suggested, go back to the door chart settings as a 'starting' point but lower the voltage about 1 volt because of the C8 gas you have instead of the C25 that the door chart lists.

[Jonesy70]

Originally Posted by MoonRise

The PM255 has enough snot/ooomph/muscle/etc to go waaaay past the "nice sizzle" sound of a nice short-circuit transfer mode weld and into the no-sizzle spray transfer mode weld.

Especially with a tank of C8.

If you keep cranking up the voltage and amperage (wire speed) with that machine, you can and will go past the parameters of a short-circuit transfer weld and into the parameters for spray mode. If you don't go quite that far (especially with the voltage), you end up in globular-mode weld.

Step one, do some PM on the machine. Blow/vac out the wire compartment, check all contact lugs for tightness, check the gun and tip, maybe blow out the liner to clear out crud from there (see the manual for how to do that).

Next, like David suggested, go back to the door chart settings as a 'starting' point but lower the voltage about 1 volt because of the C8 gas you have instead of the C25 that the door chart lists.

I agree, as I was reading the post, I believe that you are in spray mode if you are getting the hot sizzle sound...if you are getting sparks and a crackle, you are in short circuit mode. Booth modes will work, spay is smoother but hotter, short arc is easier to minipulate and not as high on the volts

[Gearjam]

It Will go Into spray...But...The heat Is way Up there...If I go to the door settings...Its way too cold

I blew the liner out yesterday...there was some dust In It...but made no difference...all lugs are clean and tight.

Just for the record...I can still work With this machine ,and a non welder would think that the weld looks good...But I can tell that there not top notch...I need to get that sizzle sound...the sweet spot...you guys know what I mean. I will take another look at the machine...If you guys think of anything else let me know...and thanks for all your suggestions and concerns

[David R]

Mig or short circuit wires poop out at about 300 ipm. Just look at your chart, or look at ESAB website for their recommendations for short circuit. If you want more balls, you need to go to bigger wire. Go back to the .045 and see.

David

[rgunn1]

Is the wire actually feeding out at the rate the machine says it's running? By that I mean, have you just run wire out of the end of the nozzle and checked the speed? I'm wondering if your drive rolls are slipping and it's not actually feeding adequately. You may have the drive rolls set up for .045 or something. I may be off base here, but it is something to check if you haven't.

[ace4059]

On my PM I need to add about 30-50 IPM on the recommended WFS, I keep the voltage the same as the recommended. Yes, lincoln's settings are a little cold but with a little increase in WFS they seem to work just fine. Also I think 75/25 would be a little better for short arc. I have never liked 90/10 or 92/8 for short arc. Now that gas for spray arc is a different story.

[David R]

I been thinkin......

I use 92/8 (C-8) and have to adjust the inductance on my machine different from when I use C/25.

The inductance on your machine is pre set, for C/25. With C-8, I get a "double short" especially if the voltage is too high. Try some C/25 or even Co2 before you condem your machine.

David

[Billdacat]

I am a novice welder but a very experienced EE.
I am suspecting there is an open diode in the rectifier circuit. A bad diode causes the output voltage to pulse at a 30Hz rate. (1/2 of 60 Hz.) This would cause the symptoms of half-a$$ performance
A low tech way of checking for this condition is to connect a motor run capacitor in series with a low wattage light bulb. (Clear oven light from the super market) If the output is pulsing, the light bulb will glow. If the output is smooth DC; then the light will not glow at all.