milling machine rotary table dividing head factory

Dividing heads allow you to divide a circle into equal fractions conveniently. Anything that involves regular action around a circle is a candidate for a dividing head.

A rotary table has no stops so it is not convenient to do large numbers of things at equal intervals because you would have to painstakingly determine the interval. Also, the rotary table does not divide the circle. For example, if you were making 13 equally spaced operations using a rotary table you would have to calculate some wierd angle for each operation and dial it in--a tedious process. For example, here are the 13 angles for a circle division:

Do you want to manually set each of these values? Have fun doing that. Now, imagine doing it for 53 divisions. You will be there all night. Not only that, the error will be a lot more than a dividing head.

The indexing plate is a machine tool accessory that holds the workpiece on the chuck or between two pinnacles and rotates, indexing and positioning it. Plate connected with rotary indexing table is in Diameter: 4"/100mm and Thickness: 0.28"/7mm, good for rotary tables in Model HV-3, HV-4, HV-5, HV-6, TS160. Perfect to use with dividing head for milling table.

This plate can be used either directly, or through a geared dividing mechanism. In direct indexing the workpiece and plate rotate in a 1-to-1 ratio, and holes are used directly. That is, a plate with 12 holes can divide the workpiece into 2, 3, 4, 6, or 12 equal segments. A dividing head incorporates an internal gear ratio (usually 40:1, 60:1, or 90:1) with the same plates. In doing so, the dividing head enables many more combinations than just direct indexing.

For example, imagine a plate with 15 equally-spaced holes and a dividing head with a 40:1 gear reduction. In direct indexing, a workpiece could be divided into 3, 5, or 15 equal segments. Using the dividing head, the same workpiece could be divided into 2, 3, 4, 5, 6, 8, 10, 12, 15, 20, 25, 30, 40, 50, 60, 75, 100, 120, 150, 200, 300, or 600 segments. Essentially, the dividing head acts as if it’s a direct indexer with 600 holes; 15 holes in the actual plate * 40:1 gear ratio. Let’s look at how some of these combinations are possible.

Rotary tables are mounted horizontally, and most can also be mounted vertically. In both cases only at 90° to the mill table. A Dividing Head is always vertical, but can be tilted through 90°.

Dividing heads are always fitted with "indexing plates" (holed wheels and clock hands), allowing a wide range of angles to be turned. The indexing mechanism can do intermediate angles. Rotary tables can be fitted with indexing plates as an accessory, but usually the number of angles supported is limited compared to a dividing head. (A generalisation. And, because rotary tables do all common angles, the limitation may not matter.)

Rotary tables are more convenient for general work because most jobs are mounted at 90° or 180° relative to the milling table. Possibly more robust than a dividing head for rough work. When close accuracy isn"t needed, jobs can be spun rapidly by the rotary table without cranking the handle - a time saver. When accuracy is needed the handle and worm are engaged. Usually there"s a vernier scale sufficiently accurate for most work. The handle is also relatively fast because most simple angles can be produced with it. For example, easy to crank from 0, 60, 120, 180, 240, 300, 0 to cut a hexagon head. Unfortunately not all angles are "simple"!

Indexing plates are so awkward that driving a Rotary Table with a stepper motor and microcontroller is popular. You simply tell the controller how many divisions are needed, press "Go", and the computer does the rest. Apart from reducing brain strain and automating a tedious task, the computer eliminates most mistakes. Computers don"t get sums wrong, have excellent memories, and are hard to distract! Also, a computer and stepper motor will do a good job of angles too complicated for the Indexing plates.

Generalising again, I suggest most people, most of the time, only need a rotary table. I see Dividing Heads as specialist tools and have never felt the need for one. For the same reason I drive an ordinary small car rather than a Land Rover. The closest I get to off-road driving is a supermarket car park! You might live on a farm...

Unless there"s a specific reason for needing a Dividing Head, I wouldn"t spend money on one. My rotary table is used a lot, in contrast a Dividing Head is only "nice to have".

I have used it in the vertical position to cut a 107 tooth gear which isn"t covered by any of the dividing head wheels I"ve got. I set up an excel spreadsheet with the angle required for each tooth which isn"t as easy as it sounds as the rotary table is calibrated in degrees/minutes/seconds rather than decimal degrees so it took a bit of figuring out how to do it.

Mophorn Dividing Head BS-0 5Inch 3 Jaw Chuck Dividing Head Set Precision Semi Universal Dividing Head for Milling Machine Rotary Table Tailstock Milling Set (5 Inch Chuck)

Amazon.com : Mophorn BS-0 Dividing Head 5 Inch, Precision Dividing Head Set with 5" 3-jaw Chuck & Tailstock Dividing Plates for Milling Machine : Garden & Outdoor

Amazon.com : Mophorn BS-0 Dividing Head 5 Inch, Precision Dividing Head Set with 5" 3-jaw Chuck & Tailstock Dividing Plates for Milling Machine : Garden & Outdoor

Amazon.com : Mophorn BS-0 Dividing Head 5 Inch, Precision Dividing Head Set with 5" 3-jaw Chuck & Tailstock Dividing Plates for Milling Machine : Garden & Outdoor