Cornwell Tools CAT-3780 User manual

1CAT-3780 Rev. 053007
CAT-3780 3/4" Dr. Composite Housing Impact Wrench
SPECIFICATIONS
• Operating Instructions • Warning Information
• Parts Breakdown
Some dust created by power sanding, sawing, grinding, drilling, and other construction
activities contains chemicals known to cause cancer, birth
defects or other reproductive harm. Some examples of these chemicals are:
• lead from lead-based paints,
• crystalline silica from bricks and cement
and other masonry products, and
• arsenic and chromium from
chemically-treated lumber.
Your risk from these exposures varies, depending on how often you do this type of
work. To reduce your exposure to these chemicals: work in a well ventilated area, and
work with approved safety equipment, such as those dust masks that are specially
designed to filter out microscopic particles.
ALWAYS READ
INSTRUCTIONS BE-
FORE USING POWER
TOOLS
ALWAYS WEAR
SAFETY GOGGLES
WEAR HEARING
PROTECTION
AVOID
PROLONGED
EXPOSURE TO
VIBRATION
Max Torque:....................................1,300 ft./lbs.
Working Torque: ................... 200 - 1,000 ft. / lbs.
Free Speed:........................................ 7,500 RPM
Overall Length: .............................................8.2"
Net Weight: ............................................ 6.9 lbs.
Air Inlet:............................................... 3/8" NPT
Min. Hose Size:........................................... 1/2"
CAT-3780
3/4" Dr.
Composite Housing
Impact Wrench
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2CAT-3780 Rev. 053007
CAT-3780 3/4" Dr. Composite Housing Impact Wrench
FAILURE TO OBSERVE THESE WARNINGS COULD RESULT IN INJURY.
THIS INSTRUCTION MANUAL CONTAINS
IMPORTANT SAFETY INFORMATION.
READ THIS INSTRUCTION MANUAL CAREFULLY
AND UNDERSTAND ALL INFORMATION
BEFORE OPERATING THIS TOOL.
• Always operate, inspect and maintain
this tool in accordance with American
National Standards Institute Safety Code
of Portable Air Tools (ANSI B186.1) and
any other applicable safety codes and
regulations.
• For safety, top performance and maximum
durability of parts, operate this tool at 90
psig 6.2 bar max air pressure with 1/2"
diameter air supply hose.
• Always wear impact-resistant eye and face
protection when operating or performing
maintenance on this tool. Always wear
hearing protection when using this tool.
• High sound levels can cause permanent
hearing loss. Use hearing protection as
recommended by your employer or OSHA
regulation.
• Keep the tool in efficient operating
condition.
• Operators and maintenance personnel must
be physically able to handle the bulk, weight
and power of this tool.
• Air under pressure can cause severe injury.
Never direct air at yourself or others.
Always turn off the air supply, drain hose of
air pressure and detach tool from air supply
before installing, removing or adjusting any
accessory on this tool, or before performing
any maintenance on this tool. Failure to
do so could result in injury. Whip hoses
can cause serious injury. Always check for
damaged, frayed or loose hoses and fittings,
and replace immediately. Do not use quick
detach couplings at tool. See instructions for
correct set-up.
• Air powered tools can vibrate in use.
Vibration,repetitivemotionsoruncomfortable
positions over extended periods of time
may be harmful to your hands and arms.
Discontinue use of tool if discomfort, tingling
feeling or pain occurs. Seek medical advice
before resuming use.
• Place the tool on the work before starting
the tool.
• Slipping, tripping and/or falling while
operating air tools can be a major cause of
serious injury or death. Be aware of excess
hose left on the walking or work surface.
• Keep body working stance balanced and
firm. Do not overreach when operating the
tool.
• Anticipate and be alert for sudden changes
in motion during start up and operation of
any power tool.
• Do not carry tool by the hose. Protect the
hose from sharp objects and heat.
• Tool shaft may continue to rotate briefly
after throttle is released. Avoid direct
contact with accessories during and after
use. Gloves will reduce the risk of cuts
or burns.
• Keep away from rotating end of tool. Do not
wear jewelry or loose clothing. Secure long
hair. Scalping can occur if hair is not kept
away from tool and accessories. Choking
can occur if neckwear is not kept away from
tool and accessories.
• Impact wrenches are not torque control
devices. Fasteners with specific torque
requirements must be checked with suitable
torque measuring devices after installation
with an impact wrench.
• Use only impact wrench sockets and
accessories on this tool. Do not use hand
sockets and accessories.
• Do not lubricate tools with flammable or
volatile liquids such as kerosene, diesel or
jet fuel.
• Do not force tool beyond its rated capacity.
• Do not remove any labels. Replace any
damaged labels.
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3CAT-3780 Rev. 053007
CAT-3780 3/4" Dr. Composite Housing Impact Wrench
Ref # Parts # Description Qty Ref # Parts # Description Qty
1 RS378001 Fixed Inlet Bushing 1 24 RS378024 Front Plate 1
2 RS378002 Exhaust Deflector 1 25 RS378025 Spring Pin 2
3 RS378003 Throttle Valve Spring 1 26 RS378026 Spring Pin 1
4 RS378004 Throttle Valve 1 27 RS378027 Hammer Cage 1
5 RS378005 Throttle Valve Seat 1 28 RS378028 Hammer 2
5-1 RS3780051 Spacer 1 29 RS378029 Hammer Pin 2
6 RS378006 Motor Housing 1 30 RS378030 Anvil 1
8 RS378008 O-Ring 1 31 RS378031 Retainer O-Ring 1
10 RS378010 Trigger 1 32 RS378032 Socket Retainer 1
11 RS378011 O-Ring 2 33 RS378033 Anvil Bushing 1
12 RS378012 Pipe 1 34 RS378034 Gasket 1
13 RS378013 Spring Pin 1 35 RS378035 Ball Bearing 1
14 RS378014 Housing Cap 1 36 RS378036 Hammer Housing 1
15 RS378015 Spring 1 37 RS378037 Spring Cap 1
17 RS378017 Gasket 1 38 RS378038 Screw 4
18 RS350TH18 Retaining Ring 1 39 RS378039 Hammer Frame Rear Spacer 1
19 RS85324 Ball Bearing 1 40 RS378040 Grease Fitting 1
20 RS378020 Rear Plate 1 41 RS378041 O-Ring 1
21 RS378021 Rotor Blade (set of 7) 1 42 RS378042 O-Ring 1
22 RS378022 Rotor 1 43 RS378043 Power Management Knob 1
23 RS378023 Cylinder 1 44 RS378044 Grip 1
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4CAT-3780 Rev. 053007
CAT-3780 3/4" Dr. Composite Housing Impact Wrench
AIR SUPPLY
Tools of this class operate on a wide range of air pressures. It is
recommended that air pressure of these tools measures 90 PSI
at the tool while running free. Higher pressure (over 90 psig;
6.2 bar) raises performance beyond the rated capacity of the
tool which will shorten tool life because of faster wear and could
cause injury.
Always use clean, dry air. Dust, corrosive fumes and/or water in
the air line will cause damage to the tool. Drain the air tank daily.
Clean the air inlet filter screen on at least a weekly schedule. The
recommended hookup procedure can be viewed in the above
figure.
The air inlet used for connecting air supply, has standard 3/8"
NPT. Line pressure should be increased to compensate for
unusually long air hoses (over 25 feet). Minimum hose diameter
should be 1/2" I.D. and fittings should have the same inside
dimensions and be tightly secured.
LUBRICATION
Lubricate the air motor daily with quality air tool oil. If no air line
oiler is used, run a 1/2 ounce of oil through the tool. The oil can
be squirted into the tool air inlet or into the hose at the nearest
connection to the air supply, then run the tool. The amount of oil
to be used is 1 ounce.
Overfilling will cause a reduction in the power of the tool.
WARRANTY
Cornwell warrants its air tools for a period of 1 year to the consumer. We will repair any air tool covered under this
warranty which proves to be defective in material or workmanship during the warranty period. In order to have your tool
repaired, return the tool to any Cornwell Authorized Warranty Center, freight prepaid. Please include a copy of your
proof of purchase and a brief description of the problem. The tool will be inspected and if any part or parts are found
to be defective in material or workmanship, they will be repaired free of charge and the repaired tool will be returned
to you freight prepaid.
This warranty gives you specific rights. You may also have other rights which vary from state to state.
The foregoing obligation is Cornwell’s sole liability under this or any implied warranty and under no circumstances shall
Cornwell be liable for any incidental or consequential damages.
Note: 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.
OPERATION
The power management knob can be used to adjust torque to
the approximate tightness of a known fastener. To set the tool to
desired torque, select a nut or screw of known tightness of the
same size, thread pitch and thread condition as those on the job.
Turn power management knob to low position, apply wrench to
nut and gradually increase power (turn power management knob
to admit more air) until nut moves slightly in the direction it was
originally set. The tool is now set to duplicate that tightness - note
power management knob setting for future use. When tightening
nuts not requiring critical torque values, run nut up flush and
then tighten an additional one-quarter to one-half turn (slight
additional turning is necessary if gaskets are being clamped).
For additional power needed on disassembly work, turn power
management knob to its fully open position. This impact wrench
is rated at 3/8" USS bolt size. Rating must be down graded for
spring U bolts, tie bolts, long cap screws, double depth nuts,
badly rusted conditions and spring fasteners as they absorb
much of the impact power. When possible, clamp or wedge the
bolt to prevent springback.
Soak rusted nuts in penetrating oil and break rust seal before
removing with impact wrench. If nut does not start to move in
three to five seconds use a larger size impact wrench. Do not
use impact wrench beyond rated capacity as this will drastically
reduce tool life.
The power management knob is also used to change the rotation
of the tool. When the power management knob is turned to the
right, the tool is in a forward or right hand rotation. When the
power management knob is turned to the left, the rotation is
reversed or left hand rotation.
NOTE: Actual torque on a fastener is directly related to joint
hardness, tool speed, condition of socket and the time the tool is
allowed to impact.
Use the simplest possible tool-to-socket hook up. Every connection
absorbs energy and reduces power.
AIR INLET
POWER
MANAGEMENT
KNOB
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