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Parts & Service: 020 8988 7400 / E-mail: [email protected] or [email protected]
DRILLING SPEEDS
Factors which determine the best speed to use are:
• Type of material being worked
• Size of hole
• Quality of cut desired
• Type of drill bit
Generally, the smaller the drill bit, the greater the required speed. In soft
material, the speed should be higher than for hard metals.
As a guide, the drill speed for a given drill bit size is according to the table
below:
DRILL VICES
In order to secure the workpiece to the table, a complete range of drill vices,
cross vices and clamps is available from your Clarke dealer.
Speed Range
(rpm)
2180 -
2580
1580
1290 -
1350
830
500 -
540
320-
420
210-
280
Wood
inches
mm
1/4
6.4
3/8
9.5
5/8
16
-
-
-
-
-
-
-
-
Zinc Diecast
inches
mm
3/16
4.8
1/4
6.4
3/8
9.5
1/2
12.5
5/8
16
-
-
-
-
Alum & Brass
inches
mm
1/8
3.2
3/16
4.8
3/8
9.5
1/2
12.5
11/16
17.5
-
-
-
-
Plastic
inches
mm
1/8
3.2
3/16
4.8
5/16
7.9
7/16
11
1/2
12.5
5/8
16
-
-
Cast Iron &
Bronze
inches
mm
3/32
2.4
1/8
3.2
1/4
6.4
11/32
8.75
1/2
12.5
5/8
16
-
-
Mild Steel &
Malleable
inches
mm
1/16
1.6
3/32
2.4
5/32
4
1/4
6.4
3/8
9.5
1/2
12.5
-
-
Cast Steel &
Med Carbon
inches
mm
3/64
1.2
1/16
1.6
1/8
3.2
3/16
4.8
5/16
7.9
7/16
11
9/16
14.5
Stainless & Tool
Steel
inches
mm
1/32
0.8
3/64
1.2
1/16
1.6
1/8
3.2
1/4
6.4
3/8
9.5
1/2
12.5