Grizzly G7948, G7947 instruction manual Changing Speeds, To change speeds

Changing Speeds

The belts in the head of the drill press must be rearranged to change speeds. A chart under the belt cover shows the belt positions needed to make the drill press run at the desired speed.

To change speeds:

1.UNPLUG THE DRILL PRESS!

2.Loosen the belt tension lock knobs (shown in Figure 26) on both sides of the headstock, so the motor is free to move.

Figure 26. Loosening lock knob (both sides).

3.Rotate the belt tension lever counterclock- wise, as shown in Figure 27, to take tension off the V-belts.

Figure 27. Using the belt tension lever.

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4.Locate the desired speed on the speed chart under the belt cover and move the V-belts to the desired V-grooves on the motor, idler, and spindle pulleys.

For Example: As indicated in the speed chart for 670 RPM (Figure 28), a belt combination of A-1.2-2creates 670 RPM.

•The “A-1” refers to the belt position between the spindle pulley and the idler pulley.

•The “2-2” refers to the belt position between the motor pulley and the idler pulley.

Note: Both belts may have to be removed before certain speed changes can be made.

A-1.4-4					BELT:B-2.4-4								BELT:
630			6 RPM					670			7 RPM
4			D	4				4			D			4
		3	C	3				3			C	3
2			B	2					2		B	2
1			A				1	1			A	1
B-2.3-3					BELT:A-1.2-2							BELT:
1650			10	RPM				2050			11 RPM
4			D			4		4			D	4
3			C	3				3			C				3
2			B	2						2	B	2
	1		A	1				1			A	1

Figure 28. Pulley combination for 670 RPM for

example.

5.Rotate the belt tension lever until the belts are tight. Tighten both lock knobs.

6.Close the cover before plugging in the machine.

G7947/G7948 12 Speed Floor Drill Press