i've got a Hilka one had it years ,runs off normal plug , up to 140amp arc, thermal cut off etc, 1.5 to 3mm rods , great for general blob welding, knocking up fly off ramps
very good for spot welding handle bar extensions in place
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have used it to fill dints in tubes but its a bit of a gamble as to weather or not you blow a hole rather then weld , one might be ok then an inch further down the tube it'll blow , braze or tig (dc inverter) is the only way for bike tubes ,
rods are dirt cheap from screwfix sold by weight so you get loads if you go for a thinner rod, takes a bit of practice to get a neat weld but very satisfying once you get the hang of it , ticks a good few boxes in the sunday workshop danger check list too