Disclaimer: I know very little about machining.
I have a rough-sawn hunk of brass about 1"x2"x3" that I would like to face mill (on the 1x2 face) in order to get it smooth and square, partly because I'm too lazy to do it with a file and partly because I'd like to learn from the experience.
I have a Jet mill-drill. The Jet takes an R-8 arbor. It came with one arbor that fits a drill chuck that it also came with; and it came with a big face cutter bit, about 2.5" in diameter with replaceable inserts, that looks like just what I need. But, it was a demo unit missing some parts, including the arbor that fits the cutter bit. The bit looks like it is supposed to slip right onto an arbor: it has a hole in the center, rather than a shaft to put into a chuck. The hole is larger than the hole in the drill chuck; the arbor that fits the chuck definitely does not fit the cutter.
The hole in the center of the bit is 25/32" in diameter, at least on the side I can measure, which is the side away from the cutting face. Can anyone tell me what kind of arbor I need, to use this cutter? Or would I be better off just throwing the cutter away unused, and buying an arbor and a cutter of some known size?
I've put pictures of the bit in question at