To make five evenly spaced holes:

1.Use the handwheel to rotate the rotary table to the zero mark on the table scale, then tighten both table locks.

Note: Make sure the handwheel and vernier scales also read zero.

2.Drill the first hole.

3.Unlock the table, then turn the handwheel 18 full turns which will rotate the rotary table to 72° as displayed on the table scale.

Note: Be careful not to pass the zero mark on the last turn. If you go past the zero mark, reverse the handwheel one full turn, then try again. This will eliminate any backlash error that occurs when reversing handwheel direc- tion.

4.Lock the table in place and drill the hole.

5.Repeat Steps 3–4, which will produce the third hole at 144°, the fourth hole at 216°, and the fifth hole at 288°.

Two Circular Slots

In this exercise, you will cut two 90° circular slots in a round workpiece, as illustrated in Figure 11.

To make two circular slots:

1.

Use the handwheel to rotate the rotary table

 

to the zero mark on the table scale, then

 

tighten both table locks.

 

Note: Make sure the handwheel and vernier

 

scales also read zero.

2.

Move the mill table to the left 1.125" along its

 

X-axis so that the spindle is above the lower

 

end of the upper slot.

3.

With a 14" end mill installed in the mill spindle,

 

make a 0.083" deep hole (approximately 13 of

 

the cutter's diameter).

4.

With the end mill continuing to cut, turn the

 

rotary table handwheel clockwise 15 full

 

turns, using care not to pass the zero mark

 

on the last turn.

5.

Raise the end mill from the workpiece, then

 

turn the rotary table handwheel counterclock-

 

wise 16 full turns—one full turn past the start-

 

ing point to eliminate the backlash error.

6.

Rotate the rotary table clockwise back to the

 

0° mark, then take an additional 0.083" deep

 

cut.

7.

Repeat Steps 4–6until the final depth of cut

 

is reached.

8.

Raise the end mill from the workpiece, then

1.125"

Radius

0.25"

90º

Start Here

 

return the rotary table back to the 0° mark.

9.

Move the mill table 2.25" to the right along its

 

X-axis to align the cutter with the end of the

 

second circular slot.

10.

Repeat Steps 3–7to complete the second

 

circular slot.

Figure 11. Two 90° circular slots.

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G9298/G9299/G9300 Rotary Table

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Grizzly G9298 owner manual Two Circular Slots, To make five evenly spaced holes, To make two circular slots