When drilling deep holes, the speed may begin to
drop off. Pull the bit partially out of the hole while the
tool is running to help clear dust.
NOTE: Do not use water to settle the dust since it
will clog the bit flutes and tend to make the bit bind
in the hole.
If a bit binds:
If the bit should bind, a built in, nonadjustable slip
clutch prevents the bit from turning when the tool is
held or braced securely. If this occurs
1. Turn off and unplug the tool.
2. Free the bit from the workpiece.
3. Clear debris from the hole.
4. Begin drilling again.
If a hammer iron gets stuck:
1. Unplug the tool.
2. Pull out bit lock and rotate it 180°.
3. Pull the tool off of the stuck accessory.
4. Remove the accessory from the workpiece.
Locking Trigger
(Cat. No. 5446-21 only)
1. To lock on the trigger, pull the trigger and press
the lock button. Release the trigger.
2. To unlock the trigger, pull and release the trigger.
Power and Service Indicators
When the tool is plugged in, the Power Indicator will
light. Unplug the tool before changing accessories
or making adjustments.
When the tool is in need of service (for example,
brushes need to be changed), the Service Indicator
will light. Stop using the tool and return it to the near-
est MILWAUKEE service facility for repairs.
Operating and Operator Force
Position the tool, grasp the handles firmly and pull
the trigger. Always hold the tool securely using both
handles to maintain control.
These hammers feature the Anti-Vibration System
to provide the operator with comfort without sacri-
ficing power or performance. Insulating elements
absorb vibration when hammering and drilling. Ideal
operator force compresses the handle slightly and
allows the tool to work aggressively while the handle
provides maximum vibration dampening. Excessive
operator force compresses the handle too far and
reduces the vibration dampening. Users will be able
to feel the difference and should adjust the force to
the handle accordingly.
A smooth, even flow of dust indicates the proper drill-
ing rate. If the speed begins to drop off when drilling
large or deep holes, pull the bit partially out of the
hole while the tool is running to help clear dust. Do
not use water to settle the dust since it will clog the
bit flutes and tend to make the bit bind in the hole.
If the bit should bind, a built-in, non-adjustable slip
clutch prevents the bit from turning. If this occurs,
stop the tool, free the bit and begin again.
Do not let the bit spin in the hole without cutting. Do
not attempt to drill through steel reinforcing rods.
Both actions will damage the carbide.
Drilling
Cold Hammering
If the hammer is stored for a long period of time or at
cold temperatures, the lubrication may become stiff
and the tool may not hammer initially or the hammer-
ing may be weak. If this happens:
1. Insert a chisel into the tool.
2. Pull the trigger and apply the chisel against a scrap
piece of concrete.
3. Turn the tool On and Off every few seconds. After
15 seconds to 2 minutes, the tool will start ham-
mering normally. The colder the hammer is, the
longer it will take to warm up.
Use MILWAUKEE core bits. Do not
WARNING
use LHS (Large Hole System) Com-
ponents with these rotary hammers. The bits
could fail, breaking apart at the threaded stud
and causing injury and property damage.
Using Rotary Percussion Core Bits
Core bits are useful for drilling larger holes for con-
duit and pipe. MILWAUKEE Heavy-Duty Core Bits
have heat-treated steel bodies with durable carbide
tips. These core bits are specially designed for fast,
accurate drilling with combined hammering and
rotary action.
1. Clean and lubricate the threads on the adapter and
core bit to make later removal easier. Screw the
threaded end of the adapter into the rear of the core bit.
2. Push the guide plate onto the pointed end of
the center pin. Insert the center pin and guide
plate assembly into the core bit. Be sure the
small end of the center pin is securely placed
into the hole in the center of the core bit.
3. Insert the adapter into the nose of the tool. Set
the action selector to the hammering with rota-
tion setting.
4. Press the center pin firmly against your center
mark, hold the tool firmly and pull the trigger.
NOTE: If a center pin and guide plate are not avail-
able, use a template or notched board to start the
hole.
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