Mike Pung posted an idea of using the stock gears as a method of indexing the rotary table instead of the stock handle. Using the a drive shaft to control the rotary tables motion the following indexes can be obtained with the stock gear set. I have come up with what I believe to be a close to definitive answer on the number of indexes available. They are as follows.
1, 2, 3, 4, 5, 6, 8, 9, 10, 12, 15, 16, 18, 20, 24, 30, 32, 36, 40, 48, 60, 64, 72, 80, 96, 120, 128, 144, 160, 192, and 240.
The stock gear set will turn the spindle a specific number of times per x-axis lead screw turn. For more information, see the Crank Handle Indexing article.
| Gear | No. of Cranks |
|---|---|
| A | 8 |
| B | 12 |
| C | 16 |
| D | 18 |
| E | 20 |
| F | 24 |
| G | 30 |
The rotary table makes one revolution for every 8 cranks or 45º increments per revolution. By multiplying the number of cranks required to make one 1 spindle rotation by 8 you can calculate the number of turns the x axis lead screw crank handle will need to turn to move the rotary table one revolution. Each crank of the lead screw handle can be used as an equal division.
| Gear | No. of Cranks / Divisions | Degree Increments |
|---|---|---|
| A | 64 | 5.625 |
| B | 96 | 3.75 |
| C | 128 | 2.812 |
| D | 144 | 2.5 |
| E | 160 | 2.25 |
| F | 192 | 1.875 |
| G | 240 | 1.5 |
These can be broken down by skipping crank revolutions. For example, using the A gear and making a cut once every 4 cranks you can index the rotary table every 16 locations. However as you can see by this example, it would be much faster to index the table using a different method. Using the numbers above, here are the possible indexes available for each gear.
| Gear | Divisions |
|---|---|
A |
2 , 4 , 8 , 16 , 32 , 64 |
B |
2 , 3 , 4 , 6 , 8 , 12 , 16 , 24 , 32 , 48 , 96 |
C |
2 , 4 , 8 , 16 , 32 , 64 , 128 |
D |
2 , 3 , 4 , 6 , 8 , 9 , 12 , 16 , 18 , 24 , 36 , 48 , 72 , 144 |
E |
2 , 4 , 5 , 8 , 10 , 16 , 20 , 32 , 40 , 80 , 160 |
F |
2 , 3 , 4 , 6 , 8 , 12 , 16 , 24 , 32 , 48 , 64 , 96 , 192 |
G |
2 , 3 , 4 , 5 , 6 , 8 , 10 , 12 , 15 , 16 , 20 , 24 , 30 , 40 , 48
, 60 , 80 , 120 , 240 |
Questions or comments or corrections, please feel free to contact me - Tim
Updated: 6/27/2010