Whatizzit?

Looks like a dividing head.

Primes, although your list is missing 2, 5 and 19. You'd multiply and divide in factors of primes to figure what number of steps on what series of holes you need to travel to get the desired rotation (e.g., in gear cutting).

Either I suppose, although indexing to a specific angle would be a little cumbersome.

Could always make more. Dave Gingery describes the process in the 7th shop-from-scrap book, deluxe accessories.

I don't know exactly, but Dave's model is used by pulling the pin, rotating the arm a certain number of holes around the disc and setting the pin into the next hole. The arm is connected to a worm gear which divides the rotation to the shaft. Yours looks similar enough. Can't say I know the brand or internal ratio.

You'd be best using it on a mill, horizontal preferred but it works "sideways" too. I suppose you could set it on the cross slide somehow and use it on a lathe.

Tim

-- "I've got more trophies than Wayne Gretsky and the Pope combined!" - Homer Simpson Website @

Indexing head, typically used in a horizontal mill to cut gears. Slap the gear blank on a mandrel, center the mandrel under the cutter, cut first tooth, rotate the head to get the desired rotation for the next gear tooth. These typically have a extra set of arms to allow a "one full turn plus 2/3rds of the way around to the next hole in the 27 hole pattern" Exact procedure depends on the interanl gear ratio and the dividing plate it comes with. Getting the procedure correct fthe 42 times for a 42 tooth gear can be a bit trying. As in trying a second time. (Ask me why I know!)

If you need a home for it, I might be > I've uploaded to the dropbox a photo of an item I qcquired last weekend. >

Doesn't sound like something I have an immediate need for. I'd probably be better off with a rotary table for my needs, although I expect I will need to make a gear sooner or later. I'm open to offers, but I'm not going to give it away.

Much appreciate the information.

Rex

RoyJ wrote:

That was from memory, but you are correct, all were prime numbers.

Thanks for the information.

Do you have any other views of it? In particular, a view square on to the end of the shaft with the crank would show whether or not it has the indexing arms designed to mark off a sector so you can advance to the next cut without having to count holes each time. (Those make it a lot easier to use for cutting gears and the like.)

Also, another view -- perhaps from the other side from the first I requested -- might show whether it can be tilted at angles other han parallel to the bed.

Note that the spindle is both equipped with a socket for a standard taper (usually B&S taper for indexing heads, though this one might be a Morse taper -- or something else entirely), and a thread for screwing a chuck or a faceplate onto it.

The first thing to do is to make a mark on the spindle (layout dye would probably do well, so you could scribe an index line without damaging the metal of the spindle), and see how many turns of the crank are needed to bring the spindle one full turn. The most common one is

That is only one of (typically three) plates. And I am surprised to find 3, as that is often subsumed in a 12 or a 33 ring. The other two plates cover some of the gaps between the existing rings, and these all have to take into account the spindle gearing ratio.

Both should do.

Not I.

It depends on who made it -- but it can be used to generate the other plates with a bit of work. (If the head does not swivel to point up, you will need to mount it on a right-angle plate on the mill to do this. And it might be easier to use with a 3-jaw chuck mounted on it with reversed jaws to grip the other plates.

Some of that is covered above. But its basic purpose is to divide a circle into a known number of increments. This can be used for such things as cutting gear teeth, making new index plates for it, spacing holes around an object -- such as holes for mounting a backplate to a lathe chuck, or drilling evenly spaced holes for a tommy bar use to screw an adaptor onto a spindle, or to remove it.

It could even be used for decorative milling to produce something other than standard knurling on a knob -- perhaps making a fluted knob.

You will find uses for it with a mill. You can even find uses for it on a drill press, as I have.

Ideally, it should come with a center tailstock holding a center at the same height above the table as the one in the head, and with an adjustment to extend or retract the center. You can make this if you must. Otherwise, you will be limited to workpieces which can be held in a chuck threaded onto the spindle.

If it does not have provisions for setting the spindle to other angles relative to the table, it is less than with one which has that capability. Mine does have it. This one appears not to have it.

Look on eBay for a while to try to find one close to that. Consider what it may cost to get one to replace it when you discover that you do have a use for it. I kept hold of mine some twenty+ years before I got a mill (though I used it on a drill press from time to time in the intervening years).

I would keep it -- but you may not wish to.

Good Luck, DoN.