hi all. im new here, and new to mig welding. many years with a stick but wanna learn mig. something im trying to work out is what this is coated with. i have this piec of old try i want to practice with, but it has some kind of coating on it that i cant see.
ive tried hydrochloride acid, sulphuric acid, acetone, thinners, petrol, blowtorch. nothing removes it.
ive noticed that a few other pieces of scrap seem the same somehow. quite simply, i cant trike an arc on them.
what is this coating and how do i remove it?
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