Amperage

[sprinter 711651]

Hi all

I have a Lincoln 220 Compact single phase MIG. I'm have trouble getting it to weld properly. Could be me but don't think so. Here's the problems. It seems to be putting out an enormous amount of amperage. Even welding on 5mm plate, the selector needs to be down at 2 (out of 6) to stop it producing huge amounts of heat and kind of just 'boiling' the steel. Today, I had a 5 mm plate, I set welder to max just to try it, 1mm wire and within about 2 seconds it blew a hole right through the plate.... There seems to be so much energy that it just makes a molten pool that doesn't even melt to both pieces you're trying to weld, if you move the arc to the plate that is not bonding, it just all gets hot with a big bubbling pool. I'm not new to welding, so have some idea, I'm open to tips of course but could there be a problem with the welder? I contacted Lincoln and got some data to check a few things, e.g., the voltage is stepping correctly when switched from 1 to 6. Any one experienced this? Gas is good, wire feed good, just HUGE amounts of energy. Any help appreciated. Regards Scott

 

[ChrisJohnsSculpture]

If it's bubbling you may well have problem with the shielding gas or contamination of the weld metal.

 

[mike 109444]

Sprinter Did the voltages meter across the 6 settings as per Lincoln? (guess something like 1 = 16v, 2 = 17v, ect upto 6 = 24v ??) Does the welder have a 2nd socket for the earth cable, a hi amd low inductor? If so try other socket. Looking inside if there is a single inductor (may be a big coil aprox 8" long or may look like a transformer) either way it will be one of the last things connected to the back of the earth lead. Does it looked fried? If non of above then generally check connections inparticular around the diodes. Look for connections that may have/are getting hot.

 

[Drains]

Big bubbling pools would normally be a gas or possibly a bad wire issue. It shouldn't relate to the current. Even inductance issues should display different behaviour. If your voltages are complying with the Lincoln data, I'd look for other problems.

 

[sprinter 711651]

Thanks everyone. The voltages did test out correctly, I've tried different wire, different torch. When I say bubbling, I don't mean as it does with no gas, i.e., there is no porosity, just that it's ultra hot. I understand that amperage is really only adjustable by what you demand, i.e. arc length, wire gauge etc. There is only 1 earth connection. Someone has said to me that the transformer could be wrong, but if voltage is stepping correctly, then I can't see this being the case. I'm going to change the gas and see what happens. Regards Scott