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MODEL NV 50AG2 Hitachi Power Tools TECHNICAL DATA COIL NAILER NV 50AG2 SERVICE MANUAL LIST No.: E020 Jan. 2005 SPECIFICATIONS AND PARTS ARE SUBJECT TO CHANGE FOR IMPROVEMENT...
9-4. Disassembly and Reassembly of the Cap and the Magazine Section ........... 27 9-5. Disassembly and Reassembly of Nail Feeder Section ..............28 10. INSPECTION AND CONFIRMATION AFTER REASSEMBLY ........... 31 11. STANDARD REPAIR TIME (UNIT) SCHEDULES............... 32 Assembly Diagram for NV 50AG2...
2. MARKETING OBJECTIVE The Model NV 50AG2 is a coil nailer specifically designed for driving nails into plaster boards. It can drive nails of 50 mm (2") in length into plaster boards, and it is equipped with convenient functions such as the vertical nailing guide mechanism.
The nails must be driven as straight as possible so that the heads are even and the paper covering of the plaster board is not damaged. As illustrated below, the Model NV 50AG2, equipped with a unique vertical nailing guide mechanism, drives nails more vertically into the surface of plaster board than is possible with conventional nailers.
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(2) Nailing-depth adjustment mechanism The nail-driving depth can be adjusted by turning the adjuster in the Model NV 50AG2. Be sure to adjust both the air pressure used and the adjuster. Turn the adjuster to the deepest point. Set the air pressure used to 4.9 bar (5 kgf/cm , 70 psi) as a guide.
NOTE: There are nails very similar to those illustrated below in local markets. However, since dimensions other than those shown will cause jamming, faulty nail feeding, and/or damage to the tool mechanism, it is important that the customer be cautioned to ensure that only Hitachi approved nails are utilized.
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The nail connecting dimensions and coil sizes after winding are shown below. Unit: mm (inch) Sheet-collated nails 32 --- 45 2.39 --- 2.5 (1-1/4" --- 1-3/4") (.091" --- .098") (.787) (4.646) (2.047) Fig. 2 Collated and coiled nails --- 6 ---...
5-3. Nail Driving Force When the Model NV 50AG2 is used with 2.3 mm dia. x 50 mm (.091" x 2") length smooth nails to fasten two sheets of plaster board (9 mm (3/8") in thickness) onto a soft wood material, approximately 5.9 bar (6 kgf/cm 85 psi) of air pressure will drive the nails so that the nail heads become flush with the surface of the outer sheet of plaster board.
Sequential fire parts set: The sequential fire parts set is provided as an optional accessory for the Model NV 50AG2. By using this optional accessory, a nail is driven by pressing the push lever first against a workpiece and then pulling the trigger, and no nail is driven when pulling the trigger first and then pressing the push lever against a workpiece (single-shot operation).
6-1. Safety Instructions In the interest of promoting the safest and most efficient use of the Model NV 50AG2 Nailer by all of our customers, it is very important that at the time of sale the salesperson carefully ensures that the buyer seriously recognizes the importance of the contents of the Handling Instructions, and fully understands the meaning of the precautions listed on the Warning Label attached to each tool.
, 112 psi) or less]. (2) To protect the Model NV 50AG2 against rust, apply oil and perform idle driving two or three times to spread the applied oil fully inside this nailer when it is not used for a long time. Also coat the steel parts with oil.
7. MECHANISM AND OPERATION PRINCIPLE 7-1. Mechanism As indicated in Fig. 5, the structure of the Model NV 50AG2 can be generally divided into four sections: the output section, the control valve section, the driving section, and the magazine section.
7-2. Operation Principle (1) Prior to nailing (Fig. 6) 1 When compressed air is supplied to the main body, it fills the accumulator ( ////// ). Air passage (A) Head valve spring Air supply vent 2 At the same time, the compressed air flows into the Head valve Accumulator valve piston lower chamber of the control valve...
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(3) During nailing (II) (Fig. 8) 1 When the piston moves down inside the cylinder, the air under the piston flows through air passage (C) under the cylinder and is accumulated in the Cylinder return air chamber together with the compressed Cylinder hole air flowing in through the cylinder hole.
Remove abnormal nails and nails not approved by nailer is normally loaded with Hitachi. nails approved by Hitachi. load the nailer with proper nails. The nailer is loaded with abnormal nails (bent nails, nail heads too large, or too small, abnormally collated nails, deformed sheet).
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Cause Fault Inspection method Remedy (The mark * refers to main causes.) Air leaks from a gap Open the nail guide and inject Tighten screws and examine Nails fail to between the body and the air to check feeder's action. the O-rings (1AP-3).
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Nails are not completely fed Refer to Item 1. Refer to Item 1. in the injection port. Nails not approved by Hitachi are used. * The driver blade is worn. Check whether or not the Replace it. driver blade head is abnormally worn.
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Nail Check whether or not nails Use the nails approved by * Nails not approved by jamming approved by Hitachi are used. Hitachi. Hitachi are used. Check nails referring to the Remove abnormal nalis and * Abnormal nails are mixed.
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Cause Fault Remedy Inspection method (The mark * refers to main causes.) * The O-ring of plunger (A) Disassemble the control valve Replace the abnormal parts. Single is worn. section to check the O-rings Set the single shot/continous shot is of plunger (A) and valve shot change knob to a correct * The O-ring of valve piston...
8-2. Possible Causes and Corrections for Air Leakage Air leakage repairing positions Inspection priorities (1) First, check the items that are marked with an asterisk (*) in the table below. (2) Next, check the items that are marked with a double circule ( ) for any wear and/or damage.
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Cause Air leakage portion When the trigger is turned on When the trigger is turned off * Incorrect assembly of Cylinder Abnormal Piston Bumper [17] D Nose 2 Washer (A) [14] or Cylinder Packing (sections e , f deformed or cracked) [13] Deformation of Piston [12] (deformed Abnormal sealed surfaces of Cylinder...
Apply grease [Nippeco SEP-3A (Code No. 930035) or Multemp PS No.2 (Code No. 939536)] to the O-rings and the O-ring sliding area. When installing the O-rings, exercise care to avoid scratches and dust. Lubricants required: Hitachi pneumatic tool lubricant 1 oz. (30 cc) Oil feeder (Code No.
9-2. Disassembly and Reassembly of the Output Section (1) Disassembly and reassembly of the Exhaust Cover [4], Head Valve (A) [8], Piston [12], Cylinder [16] and related parts: Tool required Top Cover [1] 4 mm hexagon bar wrench Hex. Socket Hd. Bolt M5 x 35 [2] (a) Disassembly (See Fig.
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Next, align the 4.5 mm dia. holes (2 places) of Piston Ring [9] Cylinder Washer (A) [14] with the matching 4 mm Bumper (A) [11] dia. bosses (2 pcs.) of the Cylinder Packing [13], Piston [12] and assemble them while confirming that they fit Driver blade properly into the groove of the Cylinder [16].
9-3. Disassembly and Reassembly of the Control Valve Section (1) Disassembly and reassembly of the control valve section: Tools required Roll pin removers (3 mm dia. and 2.5 mm dia.) (a) Disassembly (See Fig. 15.) Remove the Retaining Ring (E-Type) for D6 Shaft [19]. Trigger (A) [22], Change Knob (B) [55] and related parts can then be removed.
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Grip Tape [45] Tape [46] Retaining Ring (E-Type) for D6 Shaft [19] Roll Pin D3 x 18 [53] Trigger (A) [22] Steel Ball D3.97 [51] Head Valve Spring (C) [52] O-Ring (I.D 16.8) [58] Change Knob (B) [55] Valve Bushing (B) [59] O-Ring (S-18) [60] Body Ass'y [20] O-Ring (I.D 8.8) [61]...
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Body Ass'y [20] Roll Pin D3 x 18 [53] Roll pin hole Plunger (A) [66] Roll pin groove Valve Bushing (A) [68] Valve Bushing (A) [68] Fig. 18 After reassembly, ensure that Plunger (A) [66] operates smoothly. (2) Application of the Grip Tape [45] and the Tape [46]: Peel off the back paper that seals the adhesive surfaces of the Grip Tape [45] and the Tape [46].
9-4. Disassembly and Reassembly of the Cap and the Magazine Section (See Fig. 20.) Tools required 23 mm-wide wrench Flat-blade screwdriver (tip thickness of 0.5 mm to 1 mm) or a similar steel plate. Philips screwdriver (1) Disassembly and reassembly of the cap portion: (a) Disassembly: As the Cap [48] is a single-body unit equipped with M42 theads, simply fit a wrench across its diameter and turn it gently to loosen and remove it.
9-5. Disassembly and Reassembly of Nail Feeder Section Body Ass'y [20] O-Ring (1AP-3) [24] Adjuster Stopper [25] Retaining Ring for D28 Hole [77] Roll Pin D4 x 14 [26] Magazine Bushing [76] Needle Roller [27] Feed Piston Cover [75] Feeder Arm [28] Bumper [74] Feeder Spring [29] Feed Spring [73]...
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(2) Disassembly and reassembly of the Vertical Guide [35] and related parts (See Fig. 22.) (a) Disassembly Using a flat-blade screwdriver, remove the O-ring (P-4) [36] and extract the Guide Shaft [33]. The Vertical Guide [35] and Spring [32] can then be removed. (b) Reassembly can be accomplished by following the disassembly procedures in reverse.
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Feed Piston [72] Feeder Arm [28] Roll Pin D4 x 14 [26] O-Ring (1AP-20) [71] Split end Groove Feed Piston [72] Apply grease. Retaining Ring for Nose [69] D28 Hole [77] Fig. 23 Fig. 24 (4) Disassembly and reassembly of the Nail Guide [90] (See Fig. 25.) Shaft Ring [86] O-Ring (P-4) [36] Guide Lock [88]...
(b) Reassembly Reassembly can be accomplished by following the disassembly procedures in reverse. However, particular attention should be given to the following items. Prior to reassembly, thoroughly remove any foreign matter from the pawl groove of the Nail Guide [90]. Before tightening the Nylock Hex.
11. STANDARD REPAIR TIME (UNIT) SCHEDULES Variable MODEL 60 min. Fixed Work Flow NV 50AG2 Cylinder Cylinder Exhaust Cover Packing Gasket (A) Cylinder Head Valve Washer (A) Spring O-ring Head Valve Piston Bumper O-ring Head Valve (A) Piston Piston Ring...
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Hitachi Power Tools LIST NO. E020 PNEUMATIC TOOL PARTS LIST COIL NAILER 2005 • • Model NV 50AG2 (E1)
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PARTS NV 50AG2 ITEM CODE NO. DESCRIPTION REMARKS USED 880-191 TOP COVER 949-822 HEX. SOCKET HD. BOLT M5X35 (10 PCS.) 883-513 WARNING LABEL (A) 1 EXCEPT FOR H/V 880-448 EXHAUST COVER 880-441 EXHAUST COVER 1 FOR H/V 880-196 GASKET (A)
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PARTS NV 50AG2 ITEM CODE NO. REMARKS DESCRIPTION USED 872-035 DUST CAP NAME PLATE 1 EXCEPT FOR H/V 959-155 STEEL BALL D3.97 (10 PCS.) 982-454 SPRING (C) 949-518 ROLL PIN D3X18 (10 PCS.) 949-539 ROLL PIN D3X25 (10 PCS.) 880-086...
STANDARD ACCESSORIES NV 50AG2 ITEM CODE NO. DESCRIPTION REMARKS USED 875-769 SAFETY GLASSES 880-444 CASE 882-105 CASE 1 FOR H/V 877-153 PNEUMATIC TOOL LUBRICANT (30CC) 943-277 HEX. BAR WRENCH 3MM 944-458 HEX. BAR WRENCH 4MM 944-459 HEX. BAR WRENCH 5MM...