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PB700 COMBI US - W18XC1052/US - Revised 040113
TAPPING (Cont.)
2 - IN - 1 Drill Tap
When using a 2 - IN - 1 Drill Tap, this type of tap is restricted to plate thicknesses of the
diameter of the tapping size. ie: 1” = 1” plate. This is due to the length of the plain portion
of the shank after the threaded portion.
If the plate to be drilled is thicker than the diameter of the thread to be cut, the Combi
type drill and tap should be used.
Position the drill and ensure the security of the magnet on the work piece.
Set the spindle speed to the required speed, drill the hole with the drill portion of the
cutter, it may be necessary to slow the speed (depending on size) before tapping.
Always use tapping compound or cutting paste for best results and prolonged cutter life.
Allow the tap the feed through with little or no feed pressure, once the threaded section of
the tap is through the drill will stop feeding and just rotate.
Stop the spindle, switch to reverse, help the tap to begin feed up with very light upward
pressure on the feed handles.
Once the tap is out of the hole the machine can be removed.
IMPORTANT
when tapping NEVER switch the machine from forward to reverse without
allowing the motor to stop first. Switching directly from forward to reverse can damage
the motor and switchgear.
TAPPING SPEEDS rev/min
Tap Size
Mild Steel
Alloy Steel
1/4”
480
320
5/16”
360
240
3/8”
290
190
1/2”
240
160
5/8”
180
120
3/4”
145
95
1”
120
80
The tapping speeds shown above are for guidance only, condition of the cutter and
specific material conditions will dictate actual speeds required.
