Yes, it's an offensive term and the origin may seem obvious but I wanted to dig deeper. The mechanical device in a sawmill which turned (rotated) the logs in order to saw a new face was known as a "sawmill nigger"--even as late as the early 60's, USA patents for the devices still used that term for the device.
A search pulled up only a mason's term of nigged or nigging from the term nidge which is to dress a stone with a pick or kevel (origin uncertain). I was wondering if the currently offensive term "nigger" in sawmill equipment may come from similar roots and not really be the offensive version we jump to today. Is there a root similar to nigging that may apply to the sawmill machinery/event or is it more likely that the offensive meaning is the true one, that job being a low skilled grunt work which was likely relegated to folks of color? Can anyone find the actual origin of nidge and could it possibly be the origin when used as "sawmill nigger"?
I am restoring a large 1920's sawmill for the local museum and the research led me down this prickly path...I'm not just a crackpot who wanted to use that offensive term over and over. I'd like to suss out the actual history behind the term.