Hitachi NV 90HMC Manual

The new Model NV 90HMC is a high-pressure type [3-1/2" (90 mm)] of coil nailer. High-pressure nailer series
products have already been introduced to the Japanese market and become popular nationwide. This new
product offers higher punching force about three times greater than that of conventional nailers, in order to
reduce its size and weight. The new Model NV 90HMC also features strong punching force, a nose switch
mechanism, blow nozzle, dual action trigger, and a tool-less adjuster. Please expand sales of the new Model
NV 90HMC Nailer.
PRODUCT NAME
Hitachi 3-1/2” High Pressure Coil Nailer
Model NV 90HMC
• Floor and wall framing
• Truss and window built-up
• Subflooring and roof decking
• Crate and pallet construction
MARKETING OBJECTIVE
APPLICATIONS
SELLING POINTS
SPECIFICATIONS AND PARTS ARE SUBJECT TO CHANGE FOR IMPROVEMENT.
LIST No.
NV 90HMC: E061
Dec. 2009
International Sales Division
N
[NEW FEATURES]
Lightweight and Compact
Powerful
Nose switch mechanism
Blow nozzle
Dual action trigger
Tool-less adjuster
Easy nail loading
Lock mechanism of trigger

REMARK:
• For more information about HANDLING INSTRUCTIONS, visit our website at:
http://www.hitachi-koki.com/manual_view_export/
• Throughout this TECHNICAL DATA AND SERVICE MANUAL, a symbol(s) is(are) used in the place of
company name(s) and model name(s) of our competitor(s). The symbol(s) utilized here is(are) as follows:
Competitors
Symbols Utilized
Company Name Model Name
PMAXHN90

CONTENTS
Page
SELLING POINTS -------------------------------------------------------------------------------------------------------------- 1
SPECIFICATIONS -------------------------------------------------------------------------------------------------------------- 3
1. Specifications------------------------------------------------------------------------------------------------------ 3
2. Nail Selection------------------------------------------------------------------------------------------------------ 4
3. Nail Punching Force --------------------------------------------------------------------------------------------- 4
4. Adjusting the Nailing Depth ------------------------------------------------------------------------------------ 6
5. Dual Action Trigger----------------------------------------------------------------------------------------------- 6
COMPARISON WITH SIMILAR PRODUCTS---------------------------------------------------------------------------- 7
1. Comparison of Specifications --------------------------------------------------------------------------------- 7
PRECAUTIONS ON SALES PROMOTION ------------------------------------------------------------------------------ 8
1. Safety Instructions ----------------------------------------------------------------------------------------------- 8
TROUBLESHOOTING GUIDE -------------------------------------------------------------------------------------------- 10
1. Troubleshooting and Repair -------------------------------------------------------------------------------- 10
2. Possible Causes and Corrections of Air Leakage------------------------------------------------------ 15
REPAIR GUIDE---------------------------------------------------------------------------------------------------------------- 18
1. Precautions on Disassembly and Reassembly --------------------------------------------------------- 18
Assembly Diagram for NV 90HMC

-1-
Lightweight and Compact
Thanks to higher punching pressure about three times greater than that of conventional nailers, both nailer
size and weight are reduced.
Powerful
Powerful punching force about 1.3 times greater than that of our conventional NV 90AH Nailer.
High pressure nailer Conventional nailer High pressure nailer
Model NV 90HMC NV 90AB P
Weight 2.5 kg (5.5 lbs.) 3.0 kg (6.6 lbs.) 2.5 kg (5.5 lbs.)
Height 322 mm (12-11/16”) 389 mm (15-5/16”) 327 mm (12-7/8”)
Punching force ratio 1.3 11.1
Nose switch mechanism
Capable of changing outlet sizes (“Small” and “Large”) according to nail head sizes for using various kinds
of nails. (Select a nose according to the head size of nails you use.)
Outlet size ”Small” Outlet size ”Large”
Nail head
diameter
ø 6.0 to ø 7.5 mm
(0.236” to 0.295”)
ø 7.5 to ø 8.6 mm
(0.295” to 0.339”)
Nose
switch
Blow nozzle
Equipped with a blow nozzle, which is very convenient in keeping the work area clean.
SELLING POINTS
Turn down the
switch lever. Turn up the
switch lever.
7.0 mm
(
0.276”
)
9.0 mm
(
0.354”
)

-2-
Dual action trigger
This function automatically switches between "Single sequential actuation mode" and "Contact actuation
mode" according to the operation sequence. This function can prevent unwanted double firing in "Single
sequential actuation mode."
Tool-less adjuster
Rotating this adjuster adjusts the nailing depth (sink quantity of the nail head).
Easy nail loading
When you open the nail magazine cover, the nail holder automatically tilts toward you so that you can easily
change nail rolls.
Lock mechanism of trigger
This lock mechanism locks the trigger so that it cannot be pulled.
Shallow
Deep
A
djuste
r

-3-
1. Specifications
Model
Item NV 90HMC
Punching system Reciprocating piston type
Operating pressure 12 to 23 kgf/cm2(170 to 320 psi, 12 to 23 bar) (Gauge pressure)
Punching speed Min. 3 pcs./sec.
Weight 2.5 kg (5.5 lbs.)
Dimensions
(Length x Height x Width)
281 mm x 322 mm x 132 mm
(11-1/16" x 12-11/16" x 5-3/16")
Nail feed system Reciprocating piston type
Nail capacity 150 to 300 (1 roll)
Air consumption 2.3 ltr/cycle at 20 kgf/cm2
(.081 ft3/cycle at 280 psi) (2.3 ltr/cycle at 20 bar)
Air inlet Air plug for high pressure nailer
Air hose Air hose for high pressure nailer
(Inner diam.: 5 to 6 mm (13/64” to 15/64”))
Packaging Corrugated cardboard box (sleeve type)
Packaging dimensions
(Length x Height x Width)
355 mm x 410 mm x 170 mm
(14" x 16" x 6-11/16")
Standard accessories
• Case (Code No. 886432)
• Eye protector (Code No. 875769)
• Oiler (30 cc) (Code No. 883136)
• Nose cap (A)(Code No. 886889)
Optional accessories
• Pneumatic tool lubricant (1 oz oil feeder) (Code No. 877153)
• Pneumatic tool lubricant (4 oz oil feeder) (Code No. 874042)
• Pneumatic tool lubricant (1) (Code No. 876212)
NOTE: The Model NV 90HMC applies higher punching force than that of conventional nailers. The
customer must therefore procure an air compressor and an air hose designed for high-
pressure nailers.
The air plug of the Model NV 90HMC is exclusively designed for high pressure and cannot be
connected to any air hoses and compressors that are generally used at much lower air
pressures. Never modify the air plug for lower pressure.
SPECIFICATIONS

-4-
2. Nail Selection
The Model NV 90HMC utilizes common wire-collated and sheet-collated nail coils of 150 to 300 round-head
nails. Applicable nail dimensions are shown below. However, genuine HITACHI nail coils should be used to
assure satisfactory nailing quality.
CAUTION: Ensure that nails are as specified in Fig. 1. Using other nails will cause nail jams and
consequent nailer damage.
Fig. 1 • Dimensions of nails
Wire-collated coil nails Sheet-collated coil nails
Min. Max. Min. Max.
3. Nail Punching Force
Fig. 2 shows by type of wood and nail the nailer output energy provided by the supply pressure, and the
nailing energy required for punching nails flush. Air pressure exceeding the intersecting point between
nailer output energy and the required nailing energy for punching nails ensures fully punched nails.
For example, when punching a nail measuring 3.8 mm in dia. x 90 mm in length (0.148" x 3-1/2") into a
workpiece of hemlock with the Model NV 90HMC, pressure of about 19.6 bar (20 kgf/cm2, 280 psi) enables
the nailer to punch the nail flush with the wood surface. Any higher pressure causes the nail head to sink
below the wood surface.
Fig. 2 should be used only as a reference because the values indicated vary depending on the type of
wood, moisture content, and grain of wood.
6 mm
(0.236”)
2.5 mm
(0.099”)
45 mm (1-3/4”)
8.6 mm
(0.339”)
3.8 mm
(0.148”)
90 mm (3-1/2”)
6mm
(0.236”)
2.5 mm
(0.099”)
45 mm (1-3/4”)
6.5 mm
(0.256”)
3 mm
(0.118”)
50 mm (2”)

-5-
Required nailing energy Nailer output energy
Fig. 2 • Required nailing energy and nailer output energy
-5-

-6-
Fig. 3 Fig. 4
4. Adjusting the Nailing Depth
The nailing depth can be adjusted by simply turning the adjuster.
* Adjusting the adjuster (Fig. 3)
• Conduct test punching. If the nail sinks too deep, turn the adjuster knob toward the Shallow position
( mark). If the nail sinks too shallow, turn the adjuster knob toward the Deep position ( mark)
(see Figs. 3 and 4). The nail sink quantity is changed 1 mm per rotation of the adjuster knob.
• Do not push up the pushing lever when turning the adjuster.
• Set the lock lever to the "FREE" position when punching nails.
5. Dual Action Trigger
The Model NV 90HMC is equipped with an automatic mode switching mechanism that automatically
switches between "single sequential actuation mode" and "contact action mode".
(1) Punching operations (automatic switching between single sequential actuation mode and contact action mode)
(1) (2) Nail
driven (3) Nail driven
Single
sequential
actuation
mode
Depress the pushing
lever.
Pull the trigger.
Driven
Depress the pushing
lever.
Not driven
Contact
action
mode
Pull the trigger. Depress the pushing
lever.
Driven
Depress the pushing
lever.
Driven
(2) Precautions on using the dual action trigger
• Nails are not punched even with the pushing lever again pressed against the workpiece and the trigger
pulled in single sequential actuation mode. To punch nails continuously, remove your finger from the
trigger and operate according to the contact action procedure.
• Note that when you raise the Model NV 90HMC from the floor (after pressing the pushing lever against
the floor) with the trigger pulled, single sequential actuation mode is automatically selected. Therefore,
nails are not punched even when you press the pushing lever against the workpiece. Release the
trigger and operate according to the procedure of the desired mode.
Shallow
Deep
A
djuste
r
Lock
Lock leve
r
Free
Flush
Too deep
(Turn the knob
toward shallow
side.)
Too shallo
w
(Turn the
knob toward
deep side.)

-7-
1. Comparison of Specifications (Superior specifications: )
HITACHI
Maker
Model
Item NV 90HMC
(High pressure nailer)
NV 90AB
(Conventional nailer)
P
(High pressure nailer)
Operating pressure
12 to 23 bar
(12 to 23 kgf/cm2)
(170 to 320 psi)
4.9 to 8.3 bar
(5 to 8.5 kgf/cm2)
(70 to 120 psi)
12 to 23 bar
(12 to 23 kgf/cm2)
(170 to 320 psi)
Weight 2.5 kg (5.5 lbs.) 3.0 kg (6.6 lbs.) 2.5 kg (5.5 lbs.)
Dimensions (L x H x W)
281 mm x 322 mm x 132 mm
(11-1/16” x 12-11/16” x 5-3/16”)
292 mm x 389 mm x 132 mm
(11-1/2” x 15-5/16” x 5-3/16”)
294 mm x 327 mm x 129 mm
(11-1/2” x 12-7/8” x 5”)
Punching force ratio 1.3 11.1
Nail capacity 300 nails 300 nails 300 nails
Magazine type Top loading
(Easy nail loading) Top loading Top loading
Blow nozzle Provided None None
Driving depth
adjustment mechanism Tool-less Tool-less Tool-less
Single actuation/contact
actuation selector Automatic Manual Automatic
Nose cap Provided Provided Provided
Free angle plug None None Provided
Outlet (size) Switching type
(ø 7 mm, ø 9 mm)
Fixed type
(ø 8 mm)
Fixed type
(ø 8 mm)
Exhaust direction Forward 360°changeable Side
Handle grip Rubber Rubber Rubber
Trigger lock Provided None Provided
Collation Wire and Sheet Wire Wire and Sheet
Head dia. 8.6 mm (0.339") 7.9 mm (0.311") 7.7 mm (0.303")
Shank dia. 3.8 mm (0.148") 3.8 mm (0.148") 3.8 mm (0.148")
Applicable
nails
Length 45 mm to 90 mm
(1-3/4" to 3-1/2")
45 mm to 90 mm
(1-3/4" to 3-1/2")
45 mm to 90 mm
(1-3/4" to 3-1/2")
COMPARISON WITH SIMILAR PRODUCTS