Grizzly g0749, g0746 owner manual Leadscrew End-Play Adjustment, Gib Adjustment, Cross Slide Gib

Models: g0749 g0746

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Leadscrew End-Play

Adjustment

After a long period of time, you may find that the leadscrew develops excessive end play. This lathe is designed so that end play can be removed with a simple adjustment.

Items Needed

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Spanner Wrench

1

To remove leadscrew end play:

 

1.disCONNECT LATHE FROM POWER.

2.loosen the outer spanner nut (see Figure 128).

Inner Spanner Nut

Leadscrew

Outer Spanner Nut

Figure 128. Leadscrew and spanner nuts.

3.place a dial indicator on the end of the leadscrew.

4.Rotate the carriage handwheel to move the carriage toward the tailstock, then tighten the inner spanner nut (see Figure 128) until there is 0.001"–0.002" of end play.

5.tighten the outer spanner nut until it is snug against the inner spanner nut to secure the setting.

Model G0746/G0749 (Mfg. Since 3/13)

Gib Adjustment

The goal of adjusting the gib screws is to remove sloppiness or "play" from the ways without over- adjusting them to the point where they become stiff and difficult to move.

In general, loose gibs cause poor finishes and tool chatter; however, over-tightened gibs cause premature wear and make it difficult to turn the handwheels.

The cross-slide and compound slide on this lathe each use a long steel wedge called a gib that is positioned between the component and its dovetailed-ways. A gib screw at one end moves the gib. Depending upon which direction the gib moves, the space between the sliding ways increases or decreases to control the rigidity of the cross slide and compound slide.

Before adjusting the gibs, loosen the locks for the devices so the gibs can slide freely during adjust- ment, then lubricate the ways.

The gib adjustment process usually requires some trial-and-error. Repeat the process as nec- essary until you find the best balance between loose and stiff movement. Most machinists find that the ideal gib adjustment is one where a small amount of drag or resistance is present, yet the handwheels are still easy to move.

Tools Needed

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Standard Screwdriver #2

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Slotted Screwdriver #2

1

Cross Slide Gib

Make sure the ways and leadscrew have been cleaned and re-lubricated before beginning any adjustments. Refer to Ball Oiler Lubrication on Page 70 for instructions and lubricant specifica- tions.

To adjust the cross slide gib:

1.disCONNECT LATHE FROM POWER!

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Grizzly g0749, g0746 Leadscrew End-Play Adjustment, Gib Adjustment, Cross Slide Gib, To remove leadscrew end play