what to look for in a used stick welder

[bigballer]

looking into a stick welder for repairs/jobs around the farm and i found this, i have no idea what to look for in a used welder, can anyone comment?

Miller Thunderbolt Welder AC/DC

 

[bigballer]

here is a picture of the plug:

 

[flyerdan]

Aside from the splice job on the power cord, that looks like a pretty well preserved specimen. Check to make sure that the fan runs smoothly, without any squeaks or clattering. The amperage core should move throughout its travel without binding (if it's a little stiff it probably needs cleaning and a spot of lube). The plug ins for the leads should fit snugly and not fall out just by moving the cables. And of course if you do get it autopsy that splice.
Check out the leads for big cracks in the insulating jackets and overall condition of the ground clamp and stinger.
I believe that Millers have a pretty high open circuit voltage so striking and maintaining an arc is a lot easier than say a Lincoln tombstone which has a 24v ocv. Should make a pretty nice welder for you, it's at the top of the price range for stick machines as the market is flooded with them now.

 

[rhett]

what "flyerdan" says-

Miller Thunderbolt AC/DC 902775 Manual

230 Amps AC
150 Amps DC, at 25 volts, 20% duty cycle

 

[dex3361]

Those are good general purpose welders. Crank the adjustment up all the way and down all the way. If it feels raspy in places it has likely been overheated. I have used various buzz box welders for 30 years and they have served me well. :thumbsup:

 

[bigballer]

thanks for the tips really appreciate, according to this site it looks like it was built in 1987, 25 years old..

Miller - Service - Serial Number Reference Chart

 

[Shield Arc]

One thing I always look for in a used welder, is how smooth the arc is at really low amps. Any machine will feel smooth running 1/8 inch 7018 at 190-amps. But the question is, how smooth is the arc when running 3/32 inch 7018 at 55-amps?

 

[Sublifer]

One thing I always look for in a used welder, is how smooth the arc is at really low amps. Any machine will feel smooth running 1/8 inch 7018 at 190-amps. But the question is, how smooth is the arc when running 3/32 inch 7018 at 55-amps?

1/8" 7018 at 190 amps? That sounds pretty high. I tried some earlier at 150 and it was undercutting a bit. Maybe it depends a little on the brand...?

 

[Shield Arc]

The point is, any machine looks good running balls to the wall. The trick is how stable they are at very low amps.

 

[terraformer]

I got that very same welder, a 15 year old thunderbolt.

I usually run Lincoln 1/8" 6013 sticks at about 80-85 amps, AC.