Grizzly G1005Z Graduated Dials, Micro-Downfeed Handwheel, Backlash, To correct for backlash

Graduated Dials

The handwheels and the micro-downfeed adjust- ment knob have graduated dials. Each mark represents 0.001" of movement and one full revo- lution of the micro-downfeed knob equals 0.100". The graduated dials float and can be indexed or "zeroed" using the knurled knob on the dial. One full revolution of the handwheel equals 0.100".

Micro-Downfeed

Handwheel

The micro-downfeed handwheel (Figure 13) is used when vertical milling accuracy is required. Each full rotation of the micro-downfeed handwheel is equal to 0.100".

Backlash

Backlash and graduated dials are somewhat interconnected. When you change direction of the table in either axis, you must correct the gradu- ated dial for backlash. Normal recommended backlash is less than 0.010".

Note: It is up to you to determine an acceptable amount of backlash for your system. The frictional wear on your lead screw increases as backlash is reduced. Attempting to completely eliminate backlash can place excessive wear on your lead screw and decrease its operational capability.

To correct for backlash:

1.Turn the handwheel and move the table the opposite direction of your next operation.

2.Turn the handwheel to move the table in the intended direction.

3.The exact moment the lead screw catches and the table begins to move, backlash has been eliminated and the graduated dial can be "zeroed."

Note: You will not need to adjust for back- lash as long as the table keeps moving in the same direction.

Figure 13. Pinion hub lock knob.

To engage the micro-downfeed handwheel, tight- en the pinion hub lock knob clockwise against the pinion hub.

To disengage the micro-downfeed handwheel, hold the downfeed handles and loosen the pinion hub lock knob counterclockwise.

G1005Z Mill/Drill -19-