Jet Tools J- A5818 用户手册
9
LED Speed
Display
On/Off Switch
Speed control
Handwheel
Depth
Stop
Figure 2 – Operating Controls
Depth Stop
A drilling depth stop (refer to Figure 3) is provided on
the right side of the drill head. The depth stop
consists of a threaded rod with depth setting jam
nuts. The front side of the threaded rod has a depth
scale. The jam nuts are loosened and moved to the
desired depth on the scale. The upper jam nut is
then tightened against the lower nut.
the right side of the drill head. The depth stop
consists of a threaded rod with depth setting jam
nuts. The front side of the threaded rod has a depth
scale. The jam nuts are loosened and moved to the
desired depth on the scale. The upper jam nut is
then tightened against the lower nut.
Figure 3 – Depth Stop
Operating Precautions
The following operating and safety precautions must
be observed in order to avoid harm to the operator
or damage to the drill press.
be observed in order to avoid harm to the operator
or damage to the drill press.
1. The head assembly must be locked to the
column so the thrust produced by drilling will not
force the head assembly up the column.
force the head assembly up the column.
2. The work table must be locked to the column so
it will not be forced down the column.
3. Be sure the belt is tightened to the proper
tension.
4. DO NOT start to drill the workpiece until making
certain the workpiece is held down securely.
5. BEFORE turning the speed control handwheel
in either direction.
6. Point of operation protection is required for
maximum safety. This remains the responsibility
of the user/purchaser since conditions differ
between jobs.
of the user/purchaser since conditions differ
between jobs.
7. Make sure the drill is secured in the spindle or
check before attempting to use the drill press.
8. Make sure the spindle taper is clean and free of
burrs, scoring, and galling to assure maximum
gripping.
gripping.
Drilling Recommendations
Speeds for Drilling
The speed of a drill is usually measured in terms of
the rate at which the outer periphery of the tool
moves in relation to the work being drilled. The
common term for this is Surface Feet per Minute
(SFM). The relationship of SFM is expressed in the
following formulas:
the rate at which the outer periphery of the tool
moves in relation to the work being drilled. The
common term for this is Surface Feet per Minute
(SFM). The relationship of SFM is expressed in the
following formulas:
)
(
26
.
0
Inches
in
Diameter
Drill
RPM
SFM
×
×
=
)
(
8
.
3
Inches
in
Diameter
Drill
SFM
RPM
×
=
In general, the higher the speed the shorter the drill
life. Operating at the low end of the speed range for
a particular material will result in longer life. The
most efficient speed for operating a drill depends on
many variables:
life. Operating at the low end of the speed range for
a particular material will result in longer life. The
most efficient speed for operating a drill depends on
many variables:
1. Composition and hardness of material.
2. Depth of the hole.
3. Efficiency of the cutting fluid.
4. Type and condition of the drilling machine.
5. Desired quality of the hole.
6. Difficulty of set-up.
2. Depth of the hole.
3. Efficiency of the cutting fluid.
4. Type and condition of the drilling machine.
5. Desired quality of the hole.
6. Difficulty of set-up.