Hi lads just out of curiosity what size welder would I need to burn 4 mm rods .
4mm 160A up to 220A I believe
Its more about duty cycle to be fair. My Thermalarc 175 will do about a rod and a half and wait a while and it'll do it again. My diesel welder will burn them in hot all day and not get too far above idle.......
I usually start off about 175 for a 4mm
It really depends on the electrode, some will melt at about 90 amps and this can vary with AC or DC and will give little penetration, while others need around 200 amps DC to give a decent weld; it also depends on the welding plant and its output and duty cycle as a domestic plant will quickly trip out on thermal within a few rods.
My preference would be an oil-cooled machine, if you're in the workshop, no problems with duty cycles. Trouble is, to run the kinds of current 4mm rods need you'd need a 3 phase supply. I don't know much about inverters but if you can find one that handles the kind of current, suggested by @Memmeddu, with a decent duty cycle you might get away with a dedicated 20 amp circuit on single phase.
Many DC inverters of around 200 amps or higher will easily handle them and 5mm.
You have a choice of DC invertor machines running off 240 single phase around these currents, albeit over 13 amp input.
My inverter will stay in the 13A only if under 100A output current.
I can drain 16A continuously out of my powermeter , and up to 32A for 2 minutes .
I have a separate dedicated circuit for welding
32 amp single phase supply for a 180 amp oilcooled
My oil cooled pickhill will happily run 4mm rods at 165a running on a 16a single phase supply.
My inverter will run 250 amps at 16A MIG and 220A in stick.
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