Makita HR1821 User manual

19 mm (3/4") MODEL HR1821
Variable Speed
Capacities
Wood Steel Concrete
15" 10" 19"
(518") (3/8") (314"
INSTRUCTION MANUAL
No load Blows Overall Net
speed per minute length weight
0 ;/A,i:OO
0 - 3,500 321
mm 3.1 kg
(12-518") (6.8 Ibs)

IMPORTANT
SAFETY INSTRUCTIONS
(For All Tools)
WARNING:
WHEN USING ELECTRIC TOOLS, BASIC SAFE-
REDUCE THE RISK OF FIRE, ELECTRIC SHOCK, AND PER-
TY PRECAUTIONS SHOULD ALWAYS BE FOLLOWED TO
SONAL INJURY, INCLUDING THE FOLLOWING:
READ ALL INSTRUCTIONS.
1.
2.
3.
4.
5.
6.
7.
8.
9.
IO.
11.
12.
13.
KEEP WORK AREA CLEAN. Cluttered areas and benches invite injuries.
CONSIDERWORK AREA ENVIRONMENT.Don’t use power tools in damp
or wet locations. Keepwork area well
lit. Don‘t exposepower tools torain.
Don‘t use tool in presence of flammable liquids or gases.
KEEP CHILDREN AWAY. All visitors should be kept away from work area.
Don’t let visitors contact tool or extension cord.
STORE IDLE TOOLS. When not
in use, tools should be stored in dry, and
high or locked-up place
- out of reach of children.
DON’T FORCETOOL.
It will dothejob betterandsaferattheratefor which
it was intended.
USE RIGHT TOOL. Don’t force small tool or attachment to do the job of
a heavy-duty tool. Don’t use tool for purpose not intended.
DRESSPROPERLY. Don’t wear looseclothingorjewelry.They can becaught
in movingparts. Rubber gloves and non-skid footwear are recommended
whenworking outdoors. Wear protective haircoveringtocontainlonghair.
USE SAFETY GLASSES. Also use face or dust mask if cutting operation
is dusty.
DON’T ABUSE CORD. Never carrytoolby cord or yank
it todisconnect from
receptacle. Keep cord from heat, oil, and sharp edges.
SECURE WORK. Use clamps or a vise to hold work. It’s safer than using
your hand and
it frees both hands to operate tool.
DON’T OVERREACH. Keep proper footing and balance at all times.
MAINTAIN TOOLS WITH CARE. Keeptools sharp and clean for better and
safer performance. Follow instructionsfor lubricating and changing acces-
sories. Inspect tool cords periodically and if damaged, have repaired by
authorized service facility. Inspectextension cords periodically and replace
if damaged. Keep handles dry, clean, and free from oil and grease.
DISCONNECTTOOLS. When not
in use, beforeservicing, and when chang-
ing accessories, such as blades, bits, cutters.

14.
15.
16.
17.
18.
19.
20.
21.
REMOVE ADJUSTING KEYS AND WRENCHES. Form habit of checking to
see that keys and adjusting wrenches are removed from tool before turn-
ing it on.
AVOID UNINTENTIONALSTARTING. Don't carry plugged-intool withfinger
on switch. Be sure switch is
OFF when plugging in.
OUTDOOR USEEXTENSIONCORDS. Whentool is usedoutdoors, useonly
extension cords intended for use outdoors and
so marked.
STAY ALERT. Watch what you are doing, use common sense. Don't oper-
ate tool when you are tired.
CHECK DAMAGEDPARTS. Before further use of the tool,
a guard or other
part that is damaged should be carefully checkedto determine that
it will
operate properly and perform its intended function. Check for alignment
of movingparts, binding of movingparts, breakageof parts, mounting, and
any other conditions that may affect its operation. A guard or other part
that is damaged should be properly repaired or replaced by an authorized
servicecenter unlessotherwise indicatedelsewhere
in thisinstruction manu-
al. Have defective switches replaced by authorized service center. Don't
use tool if switch does not turn
it on and off.
GUARDAGAINST ELECTRIC
SHOCK. Preventbody contact withgrounded
surfaces. For example; pipes, radiators, ranges, refrigerator enclosures.
PROPER GROUNDING. This tool should be grounded while in use to pro-
tect the operator from electric shock.
EXTENSIONCORDS: Useonly three-wire extensioncords which havethree-
prong grounding-type plugs and three-pole receptacles which accept the
tool's plug. Replace or repair damaged or worn cord immediately.
VOLTAGE WARNING: Before connectingthe tool toa power source (receptacle,
outlet, etc.) be sure the voltage supplied is the same as that specified on the
nameplateof the tool. A power source withvoltage greater than that specified
for the tool can result
in SERIOUS INJURY tothe user - as well as damage to
the tool. If
in doubt, DO NOT PLUG IN THE TOOL. Using a power source with
voltage less than the nameplate rating is harmful to the motor.
3

For all groundedtools with American type plug.
GROUNDINGINSTRUCTIONS: This tool should begrounded while inuse to protect the operator
from electric shock. The
tool is equipped with athree-conductorcordand three-prong grounding-
type plug to fit the proper grounding-type receptacle. The green (or green andyellow) conductor
in the cord is the grounding wire. Never connect the green (or green and yellow) wire to a live
terminal. Your unit
is for use on 115 volts and has aplugthat looks like,Fig. "A".
An adapter Fig. "B" and
"C" is available for connecting Fig. "A" type plugstotwo-prong recap
tacles. The green-colored rigid ear, lug, etc., extending from the adapter must be connected to
a
permanentground, such as a properly groundedoutlet box.
FIG. A FIG.
0 FIG. C
Adapter
Grounding Blade Cover of Grounded Outlet Box
4

ADDITIONAL SAFETY RULES
1.
2.
3.
4.
5.
6.
7.
8.
9.
IO.
11.
Wear a hard hat (safety helmet) and an ear protector if necessary.
Be sure the drill bit is secured in place before operation.
Under normal operation, the tool is designed to produce vibration. The
screws can come loose easily, causing a breakdown or accident. Check
tightness
of screws carefully before operation.
Incold weather or when the tool has not been usedfor a longtime, let
the
tool warm up for several minutes by operating it under no load. This will
loosen
up the lubrication. Without proper warm-up hammering operation
is difficult.
Always be sure you have a firm footing.
Be sure no one is below when using the tool in high locations.
Hold the tool firmly with both hands. Always use the side grip.
Keep hands away from rotating parts.
Do not leave the tool running. Operate the tool only when hand-held.
Do not point the tool at any one in the area when operating. The drill bit
could fly out and injure someone seriously.
When drilling intowalls, floors
or wherever ”live” electrical wires may be
encountered,
DO NOT TOUCH ANY METAL PARTS OF THE TOOL!
Holdthe tool only by the plastic handle or the side grip to prevent electric
shock
if you drill into a “live” wire.
Do nottouchthedrill bit or parts closetothe drill bitimmediately after oper-
ation; they may be extremely hot and could burn your skin.
SAVE THESE INSTRUCTIONS.
5

HOW TO USE
Bitgrease
0 Coat the drill bit shank head beforehand with a small amount (about 0.5 - 1 g; 0.02 -
0.04 02.) of bit grease. This chuck lubrication assures smooth actionand longer service
life.
Installingand removingthe drill bit
To install the drill bit, align protrusion
(A) with the red dot, then align the key
groove on the drill bitshank withthe red
dot and insert thedrill bit. Now turnthe
chuck cover
90 degrees.
I I
Fig. 1
*To remove the drill bit, turn the chuck
cover until protrusion
(A) is alignedwith
the reddot. Then slipout the drill bit.
Key-groove
I
I I
Fig. 2
Side grip
0The side grip can be swivelled
a full 360
degrees. To set it at any desired angle,
unscrew the grip counterclockwise and
swivel tothe desired position.
Then tighten
it securely. (Keep the grip
base in the barrel groove before tighten-
ingin place.)
Fig. 3
6

Depthrod
.The depth rod
is used to drill holes of
uniform depth. Loosen the thumb screw
set the depth rod to desired position,
then tightenthe thumbscrew.
Fig. 4
Handlingdust collector
0 Use the dust collector for safe, sanitary
then fix the dust collector on the end
by turning and applying pressure. Then
secure
it by turning the metal retainer
clockwise.
CAUTION:
Empty the dust collector of
its contents
after drilling every
2 or 3 holes.
overhead operations. Install the drill bit,
Dust collector
Fig. !
How to work switchover mechanism
0 For Rotation + Hammering:
Press the push rod indCDodirection.
For Rotationonly:
Press the Dush rod in&+direction.
Push rod
Lb-
CAUTION:
Press the push rod
as far as it will go.
Failure to do
so can cause rapid wear of
the switchover mechanism.
Fig. 7

Switchaction
Tool speed is increased by increasingpres-
sure on the trigger. To
start the tool,
simply pull the trigger.
Release the
triggertostop.
Speed control screw
,
Fig. t
.A speed control screw is provided so that tool speed (RPM)can be changed at the fully-
pulled trigger position. Turn the speed control screw clockwise
(+) for higher speed and
counterclockwise
(-) for lowerspeed.
CAUTION:
Before plugging in the tool, always check to
see that the triggerswitch actuates properly
and returnstothe
"OFF" positionwhen released.
Hammerdrilling operation
.Position the drill bit
at the location for
the hole, then pull the trigger.
Do not force the tool. Light pressure
gives best results. Keep the tool in posi-
tion and prevent
it from slipping away
from the hole.
When holes becomeclogged
.Do not apply more pressure when the
hole becomes clogged with chips or par-
ticles. Instead, run the tool at idle, then
remove from the hole. By repeating this
several times, the holewill
be cleaned out
completely.
Fig. 9
CAUTION:
When drilling in concrete,
it is quite possible that the drill bitcouldhit a reinforcingrod
or some other object that could cause
a kickback. Although this tool is equipped with
the torque limiter, protect yourself by holdingthe tool firmlywith both hands. (Be sure
the side grip
is securedtightly before operation.)
8

Blow-outbulb
0 Use the blow-outbulbto clean out the
hole.
Fig. 10
Anchor settingprocedure
0 The drill bit has a red markingwhichcan be usedto indicatethe anchor length. Use the
depth rodwhen drilling for setting
a number of anchors at the same depth.
ed marking chor setting tool
Put
a plug in the tip of
an anchor and hammer
it intoconcrete.
Screw in
a bolt for
fastening equipment.
Fig. fi
Drilling inwoodor metal
Set the push rodfor “rotation only.”
Then use the drill chuck and chuck
adapter (optional equipment), installing
it as described in “Installing and removing
the drill bit
(P. 6).”
CAUTION:
DO not perform “rotation + hammering“
action with the drill chuck, or the chuck
will probablybe damaged.
I
Drill chuck
\
d Fig. 12
9

MAINTENANCE
CAUTION:
Always
be sure that the tool is switchedoff and unpluggedbeforeattemptingtoperform
inspectionand maintenance.
Replacing carbon brushes
0 Both carbon brushes should be replaced
after about
150 hours of use. When the
resin insulating tip inside the carbon
brush
is exposed to contact the com-
mutator,
it will automatically shut off
the motor. If carbon brushes wear out
too quickly, ask Makita Authorized or
Factory Service Centers to determine
the cause before replacing them. Use
only Makitacarbon brushes.
*Use the screwdriver to remove the brush
holdercap
as shown in the figure.
Insulating tip
77
Fig. 1
Fig. 14
Take out the worn brush, insert the new
one and secure the brush holdercap.
I I
Fig. 15
10

Lubrication
0 Lubricate the tool every time after replacingcarbon brushes.
Run the tool for several minutesto warm
it up, then rest the tool on the table with
the chuck cover (bit)end pointingtoward
the ceiling.This will allow the old grease
to collect inside the crank housing.After
five minutes, take off the crank cap and
remove the old grease. Wipe out
all grease
inside and replace with the fresh supply
(30 9).
Fig. 16
CAUTION:
Filling with more than the specified
amount of grease (approx.
30 g; 1 02.)
can cause faulty hammering action or
a failure. Fill only with the specified
amountof grease.
CAUTION:
Do not tighten the crank cap too much,
when installing.
It is made of resin and is
subjecttobreakage.
Never use the bitgrease for lubrication of
hammer mechanism.
To maintain product SAFETY and RELIABILITY, repairs, any other maintenance and
adjustment should be performed by Makita Authorized or Factory Service Centers,
always usingMakita replacementparts.
11

ACC ESSO R I ES
CAUTION:
These accessories or attachments are recommended for use with your Makita tool specified in this
manual. The use
of any other accessories or attachmentsmight present a risk of injury to persons.
The accessories or attachmentsshouldbe used only inthe proper and intendedmanner.
0 Taper shank adapter No. 1
Part No. 798131-4
0 Taper shank adapter A
Part No. 798176-2
0 Dust collector
Part No. 122290-6
0 Depth rod
Part No. 321144-6
0 Drill chuck S10
Part No. 763056-1
1
t
0 Chuck adapter
Part No. 321832-5
0 Chuck key S10
Part No. 7634038
0 Blowout bulb
Part No. 7650096
Hex wrench 5
Part No. 7832038
0 Lock nut wrench 28
Part No. 782402-9
0 Hammer grease 30 g; 1 02.
Part No. 181490-7
*Bit grease 100 g; 3.5 oz.
Part No. 181573-3
0 Steel carryingcase
Part No. 155826-6
0 Cotter
Part No. 765010-1
12

0 Tungsten-carbide tip bits
Part No
Blt Max drilling Overall
diameter depth lenath
0 Anchors (30 sets per pkg)
Anchor outer Overall Thread
N~ 1 dyzer I leegmf: 1 Thread 1 k3;g_f; I Part NO.
No.2 11 17/16") 30 (1 3/16") W 114'' 10 1318") 798054-6
NO 2 5 12 Ill2") 35 11-318") W 5/16" 13 1112") 798056-2
NO 3 14.3 19/16") 40 I1 518") W 318'' 15 1518") 798058-8
N0.4 17.5l11/16"~50 12") W 112" 20 (13/16") 798060-1
0 Anchor setting tool
Part
No. 765012-7
Anchor setting rod (Manualsetting)
765014 3
No 25 765015 1
Makitaanchor only
Anchor settinq rod
1
0 Anchor setting rod for interior applications
(Set
by tool)
I
Anchor setting rod
Plug for interior applications
(Manual setting)
Anchor setting rod
Plug for interior aoolications
13

19 mm (3/4")
@ma ROTARY HAMMER
-
Model HR1821
Seo.--19-'84 US
Note: The switch and other part configurations
may differ from country to country.
14

MODEL HR1821
'ikM ,,!!D DESCRIPTION
Sep-19-'84 US
,!:, DESCRIPTION
MACHINE
~
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
3
1
1
1
1
1
1
1
1
1
1
1
1
4
4
1
1
1
1
1
1
1
2
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
Steel Ball 6 4
Key 4
Cylinder
Liner 20
Ball Bearing 3007
Nut M303-36
Barrel
0 Ring 40
Flat Washer 30
Spiral Bevel Gear 26
Striker
0 Ring 16
0 Ring 16
Piston
Spring Washer 6
Hex
Socket Head Bolt M6x50
Pl" 5
Makita Label
Crank Cap
0 Ring 35
Rod
Needle Bearing 810
Crank Shaft
Steel Ball 5 6
Compression Spring 6
Change Pin 8
Crank Housing
0 Ring 32
Ball Bearing 6002
Helical Gear 29
Flat Washer 15
Torque Limiter
Flat Washer 6
0 Ring 65
Ball Bearing 6200
0 Ring 30
011 Seal 13
Fan 67
ARMATURE ASSEMBLY
iAssembled Items 38 - 40 & Item 42)
Insulatnm Washer
Rubber
Pin 4
Ball Bearing 608LB
011 Sea1 21
Felt Ring 20
0 Ring 40
ea, tiouslng
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
82
83
85
86
87
88
89
90
91
92
93
-
1
3
1
1
1
1
2
1
1
1
1
1
1
1
1
1
1
1
2
2
1
4
1
2
2
1
2
3
1
2
2
1
1
1
1
1
1
1
1
1
1
1
1
1
1
-
Seal Holder
Steel Ball 6 4
Impact Bolt
0 Ring 10
0 Ring 10
Drill Holder
Key 4
0 Ring 10
0 Ring 10
0 Ring 19
Change Ring
Steel Ball 4 fl
Leaf sprrng
0 Ring 19
Flat Washer 20
Spiro Lock Washer 20
Chuck Cover
Fan Gwde
Hex Bolt M5x40 lWith Washer)
Rivet 0-5
Name Plate
Hex Nut M6
Label
Brush Holder Cap
Carbon Brush
Motor Housing
Pan Head Screw M6x16 IWith Washer)
Pan Head Screw M5x22 IWith Washer)
Handle Set lWith Item 851
Pan Head Screw M6x25 lWith Washer)
Pan Head Screw M4x18 (With Washer1
Strain Relief
CORD ASSEMBLY
IWith Cord Plug E Item 791
Cord Guard
Dust Cover
Switch
Handle Set IWith Item 741
Grip 37
Cap
Square Neck Bolt MBx35
Belt
Grip Base
Rubber Washer 4 5
Thumb Screw M5x15
FIELD ASSEMBLY
Pan Head Screw M4x8 IWith Washer)
Note The switch and other part specifications may differ from country to country
15

MAKITA LIMITED ONE YEAR WARRANTY
Warranty Policy
Every Makita tool is thoroughlyinspected and tested before leaving the factory. It is warranted to
be free of defects from workmanship and materials for the period of ONE YEAR from the date of
original purchase. Should any trouble develop during this one-year period, return the COMPLETE
tool, freight prepaid, to one of Makita’s Factory or Authorized Service Centers. If inspection shows
the trouble is caused by defective workmanship or material, Makita will repair (or at
our option,
replace) without charge.
This Warranty dses not apply where:
repairs have been made or attempted by others:
repairs are required because of normal wear and tear:
The tool has been abused, misused or improperly maintained;
alterationshave been made to the tool.
IN NO EVENT SHALL MAKITA BE LIABLE FOR ANY INDIRECT, INCIDENTAL OR CON-
SEQUENTIAL DAMAGES FROM THE SALEOR USE OFTHE PRODUCT. THIS DISCLAIMER
APPLIESBOTH DURING AND AFTER THE TERM OF THIS WARRANTY.
MAKITA DISCLAIMS LIABILITY FOR ANY IMPLIED WARRANTIES, INCLUDING IMPLIED
WARRANTIES OF “MERCHANTABILITY” AND “FITNESS FOR A SPECIFIC PURPOSE,”
AFTER THE ONE-YEARTERM OF THISWARRANTY.
This Warranty gives you specific legal rights, and you may also have other rights which vary from
state to state. Some states do not allow the exclusion or limitation of incidental or consequential
damages,
so the above limitation or exclusion may not apply to you. Some states do not allow
limitation on how long an implied warranty lasts,
so the above limitation may not apply toyou.
~~.Ltd.
11-8,J-chome. Sumiyorhi-cho,Anjo, Aichi 446, Japan
8834808065 PRINTED IN
JAPAN
1986-2-N