2.Slowly continue to turn the handwheel clock- wise to 42' as displayed on the handwheel scale (see the illustration in Figure 9).
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40 | 30 | 20 | 10 | 1 | 50 | 40 | 30 | 20 | 10 | 0 | 50 |
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Figure 9. Table set at 16° 42' 20".
3.Identify the mark on the vernier scale that is two marks or 20" to the left of the zero mark.
Note: When the handwheel is turned clock- wise, the marks to the left of the zero mark on the vernier scale are used, and when the handwheel is turned counterclockwise, the marks on the right are used.
4.Identify the mark on the handwheel scale that is immediately to the left of the vernier scale mark identified in Step 3, then slowly rotate the handwheel clockwise to align these two marks. The table is now set 16° 42' 20".
Basic Operation
In the following two exercises, it is assumed that the following statements are true before beginning the operation:
•The rotary table is properly secured to the mill table in the horizontal position.
•The rotary table is properly centered with the mill spindle.
•The workpiece is centered on the rotary table and elevated for proper machining clear- ance.
•The workpiece is securely clamped to the rotary table.
Five Evenly Spaced Holes
In this exercise, you will make five holes spaced 72° apart in a circular workpiece, as illustrated in Figure 10.
72º
Figure 10. Five holes spaced 72° apart.
Tip: When using the rotary table to machine several locations or with a complicated pattern, make a drawing with measurement details to help visualize the operation. This will reduce the risk of making errors during the operation.
G9298/G9299/G9300 Rotary Table |