Welding lead quage

westbrooklawn · Feb 13, 2012

I have two stick welders... a Miller Thunderbolt AC/DC and a Miller Maxstar 150 that I bought used from a welding pro. I find myself using the Maxstar more and more, simply because of it's size and ease of setup. The original owner had put a 35' #2 wire on the electrode lead, and a 12' #4 wire on the ground lead... it welds just fine with this setup.

Now I want to extend the ground lead to 35', and I already have 35' of spare #4 wire. This would end up with a total lead length of 70', with one lead being #2 and one being #4. I hardly ever weld over 125 amps, and with short duty cycles. Some charts indicate you can go 100' at 150 amps with #4. Other charts show that 100' at 150 amps requires #2 wire. I can't find a chart that shows what I need for 70', but I feel the combination of 35' of #2 and 35' of #4 should be fine up to 150 amps. I see no reason why the difference in lead size would matter as long as the smallest ga. wire can handle the load. What do you welding experts think?

k0ua · Feb 13, 2012

westbrooklawn said:
I have two stick welders... a Miller Thunderbolt AC/DC and a Miller Maxstar 150 that I bought used from a welding pro. I find myself using the Maxstar more and more, simply because of it's size and ease of setup. The original owner had put a 35' #2 wire on the electrode lead, and a 12' #4 wire on the ground lead... it welds just fine with this setup.

Now I want to extend the ground lead to 35', and I already have 35' of spare #4 wire. This would end up with a total lead length of 70', with one lead being #2 and one being #4. I hardly ever weld over 125 amps, and with short duty cycles. Some charts indicate you can go 100' at 150 amps with #4. Other charts show that 100' at 150 amps requires #2 wire. I can't find a chart that shows what I need for 70', but I feel the combination of 35' of #2 and 35' of #4 should be fine up to 150 amps. I see no reason why the difference in lead size would matter as long as the smallest ga. wire can handle the load. What do you welding experts think?

I looked at a couple of charts. and the ones I saw said good for up to 150 amps at 100 foot. so you are 70 foot, and you have a combination of larger stinger lead so slightly less drop. And you will be welding at 125 amps not 150.. I say go for it.

James K0UA

Oh, I am not a welding expert, nor play one on TV and I did not stay at a Holiday Inn last night either.