A dividing head is a pretty shelf decoration until you need it. When you do need it, there is no substitute. A rotary table will almost work, up to maybe 6 or 8 divisions, but isn't quite there. If you are going to cut gears from scratch, it is irreplacible. I have found many other uses as well, even some for woodworking, making jigs, fixtures, and gauges. There are a few limitations, being centered on prime numbers above about 50.
I do small work, models mostly, having several dividing heads. One is a rotary table with fraction plates fitted. One is a B&S dedicated dividing head. And somewhere is a B&S#0 clone. It's too heavy to have been misappropriated, I'm sure it's here, somewhere. The smallest is that 3-1/2 inch RT, the largest is the B&S #0 with a 1-1/2X8 threaded chuck mount.
BTW, even a clone starts at $350 m/l plus shipping. Beware of that fantastic deal for $39.95 with free shipping. The shipping alone will cost more than that. There is a "regular" scam on eBay for just that. Don't bite, it is a scam.
Another note, having read the post just before me: Most of the dedicated B&S heads, including clones, have a B&S taper socket. Not a Morse, although it measures almost like one.
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