G9749 Variable Speed Drill Press
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Choosing Speeds
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1/16" – 3/16" 3000 2500 2500 2500 3000 2500
13/64" – 3/8"
2000 1500 2000 1250 2500 1250
25/64" – 5/8"
1500 750 1500 750 1500 600
11/16" – 1"
750 500 1000 400 1000 350
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1/4" – 1/2" 2000 1500
9/16" – 1"
1500 1250
1-1/8" – 1-7/8"
1000 750
2–3" 500 350
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1/2" – 7/8" 500 500 600 600 600 500
1" – 1-7/8"
400 400 500 500 500 400
2" – 2-7/8"
300 300 400 400 400 300
3" – 3-7/8"
200 200 300 300 300 200
4" – 5"
100 100 200 200 200 100
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Carbide Insert Type 350 250
One-Piece Type
1800 500
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3/8" – 1/2" 1200 1000
5/8" – 1" 800 600
Using the Drill Bit Speed Chart
The chart shown in Figure 15 is intended as
a guide only. Always follow the manufacturer's
speed recommendations if provided with your drill
bits, cutters, or hole saws. Exceeding the recom
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mended speeds may put the operator in danger.
The speeds shown here are intended to get you
started. The optimum speed will always depend
on various factors, including tool diameter, drilling
pressure, material hardness, material quality, and
desired finish.
Some type of lubrication is often necessary to drill
materials other than wood.
Lubrication Suggestions
Wood & Cast Iron ........................................None
Plastics ........................................... Soapy Water
Brass .............................. Water-Based Lubricant
Aluminum ......................Paraffin-Based Lubricant
Mild Steel ..............................Oil-Based Lubricant
Larger bits turning at slower speeds tend
to grab the workpiece aggressively. This
can result in the operator's hand being
pulled into the bit or the workpiece being
thrown with great force. Always clamp the
workpiece to the table to prevent injuries.
Figure 15. Cutting tool speed chart.