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3921 16-Inch Variable Speed Scroll Saw
Instruction Manual
WEN 3921 16-Inch Variable Speed Scroll Saw

16″ VARIABLE SPEED SCROLL SAW
Model # 3921
bit.ly/wenvideo

IMPORTANT:
Your new tool has been engineered and manufactured to WEN’s highest standards for dependability, ease of operation, and operator safety. When properly cared for, this product will supply you with years of rugged, trouble-free performance. Pay close attention to the rules for safe operation, warnings, and cautions. If you use your tool properly and for the intended purpose, you will enjoy years of safe, reliable service.

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WEN 3921 16-Inch Variable Speed Scroll Saw - icon WENPRODUCTS.COM

TECHNICAL DATA

Model Number:
Motor: Speed:
Throat Depth:
Blade:
Blade Stroke:
Cutting Capacity:
Table tilt:
Overall dimensions:
Weight:
Includes:
3921
120 V, 60 Hz, 1.2 A
550 to 1600 SPM 16
5 pinned & pinless
9/16
2 at 90° 0° to 45°
left 26 – 3/8 by 13 by 14 – 3/4
27.5 lb
15 TPI Pinned Blade
18 TPI Pinned Blade
18 TPI Pinless Blade

GENERAL SAFETY RULES

Safety is a combination of common sense, staying alert, and knowing how your item works.
SAVE THESE SAFETY INSTRUCTIONS.
warning 2 WARNING: To avoid mistakes and serious injury, do not plug in your tool until the following steps have been read and understood.

  1. READ and become familiar with this entire instruction manual. LEARN the tool’s applications, limitations, and possible hazards.
  2. AVOID DANGEROUS CONDITIONS. Do not use power tools in wet or damp areas or expose them to rain. Keep work areas well lit.
  3. DO NOT use power tools in the presence of flammable liquids or gases.
  4. ALWAYS keep your work area clean, uncluttered, and well-lit. DO NOT work on floor surfaces that are slippery with sawdust or wax.
  5. KEEP BYSTANDERS AT A SAFE DISTANCE from the work area, especially when the tool is operating. NEVER allow children or pets near the tool.
  6. DO NOT FORCE THE TOOL to do a job for which it was not designed.
  7. DRESS FOR SAFETY. Do not wear loose clothing, gloves, neckties, or jewelry (rings, watches, etc.) when operating the tool. Inappropriate clothing and items can get caught in moving parts and draw you in. ALWAYS wear non-slip footwear and tie back long hair.
  8. WEAR A FACE MASK OR DUST MASK to fight the dust produced by sawing operations.
    warning 2WARNING: Dust generated from certain materials can be hazardous to your health. Always operate the tool in a well-ventilated area and provide for proper dust removal. Use dust collection systems whenever possible.
  9. ALWAYS remove the power cord plug from the electrical outlet when making adjustments, changing parts, cleaning, or working on the tool.
  10. KEEP GUARDS IN PLACE AND IN WORKING ORDER.
  11. AVOID ACCIDENTAL START-UPS. Make sure the power switch is in the OFF position before plugging in the power cord.
  12.  REMOVE ADJUSTMENT TOOLS. Always make sure all adjustment tools are removed from the saw before turning it on.
  13. NEVER LEAVE A RUNNING TOOL UNATTENDED. Turn the power switch to OFF. Do not leave the tool until it has come to a complete stop.
  14. NEVER STAND ON A TOOL. Serious injury could result if the tooltips or is accidentally hit. DO NOT store anything above or near the tool.
  15. DO NOT OVERREACH. Keep proper footing and balance at all times. Wear oil-resistant rubber-soled footwear. Keep the floor clear of oil, scrap, and other debris.
  16. MAINTAIN TOOLS PROPERLY. ALWAYS keep tools clean and in good working order. Follow instructions for lubricating and changing accessories.
  17. CHECK FOR DAMAGED PARTS. Check for alignment of moving parts, jamming, breakage, improper mounting, or any other conditions that may affect the tool’s operation. Any part that is damaged should be properly repaired or replaced before use.
  18. MAKE THE WORKSHOP CHILDPROOF. Use padlocks and master switches and ALWAYS remove starter keys.
  19. DO NOT operate the tool if you are under the influence of drugs, alcohol, or medication that may affect your ability to properly use the tool.
  20. USE SAFETY GOGGLES AT ALL TIMES that comply with ANSI Z87.1. Normal safety glasses only have impact-resistant lenses and are not designed for safety. Wear a face or dust mask when working in a dusty environment. Use ear protection such as plugs or muffs during extended periods of operation.

SPECIFIC RULES FOR THE SCROLL SAW

warning 2 WARNING: Do not operate the scroll saw until it is assembled and adjusted. Do not operate the scroll saw until you have read and understood both the following instructions and the warning labels on the scroll saw.
BEFORE OPERATING:

  1. Check for both proper assembly and proper alignment of moving parts.
  2. Understand the function and proper use of the ON/OFF switch.
  3. Know the condition of the scroll saw. If any part is missing, bent, or does not operate properly, replace the component before attempting to operate the scroll saw.
  4. Determine the type of work you are going to be doing. Properly protect your body including your eyes, hands, face, and ears.
  5. To avoid injury caused by pieces thrown from accessories, use only recommended accessories designed for this saw. Follow the instructions supplied with the accessory. The use of improper accessories may cause a risk of injury.
  6. To avoid contact with rotating equipment:
    – Do not put your fingers in a position where they risk contracting the blade if the workpiece unexpectedly shifts or your hand unexpectedly slips.
    – Do not cut a workpiece too small to be held safely.
    – Do not reach under the scroll saw table when the motor is running.
    – Do not wear loose clothing or jewelry. Roll long sleeves above the elbow. Tie back long hair.
  7. To avoid injury from accidental startups of the scroll saw:
    – Make sure to turn OFF the switch and unplug the power cord from the electric outlet before changing the blade, performing maintenance or making adjustments.
    – Make sure the switch is OFF before plugging in the power cord to an electric outlet.
  8. To avoid injury from a fire hazard, do not operate the scroll saw near flammable liquids, vapors or gases.
  9. To avoid back injury:
    – Obtain help when raising the scroll saw more than 10 inches (25.4 cm). Bend your knees when lifting the scroll saw.
    – Carry the scroll saw by its base. Do not move the scroll saw by pulling on the power cord. Pulling on the power cord could cause damage to the insulation or the wire connections resulting in electric shock or fire.

WHEN OPERATING THE SCROLL SAW

  1. To avoid injury from the unexpected scroll saw movement: – Use the scroll saw on a firm level surface with adequate space for handling and supporting the workpiece.
    – Be sure the scroll saw cannot move when operated. Secure the scroll saw to a workbench or table with wood screws or bolts, washers, and nuts.
  2. Before moving the scroll saw, unplug the power cord from the electrical outlet.
  3. To avoid injury from kickback:
    – Hold the workpiece firmly against the tabletop.
    – Do not feed the workpiece too fast while cutting. Only feed the workpiece at the rate the saw will cut.
    – Install the blade with the teeth pointing downward.
    – Do not start the saw with the workpiece pressing against the blade. Slowly feed the workpiece into the moving blade.
    – Use caution when cutting round or irregularly shaped work pieces. Round items will roll and irregularly shaped workpieces can pinch the blade.
  4. To avoid injury when operating the scroll saw:
    – Obtain advice from a qualified person if you’re not thoroughly familiar with the operation of scroll saws.
    – Before starting the saw, make sure the blade tension is correct. Recheck and adjust tension as needed.
    – Make sure the table is locked into position before starting the saw.
    – Do not use dull or bent blades.
    – When cutting a large workpiece, make sure the material is supported at the table height.
    – Turn the saw OFF and unplug the power cord if the blade jams in the workpiece. This condition is usually caused by sawdust clogging the line you are cutting. Wedge open the workpiece and back out the blade after turning off and unplugging the machine.

ELECTRICAL INFORMATION

GROUNDING INSTRUCTIONS
IN THE EVENT OF A MALFUNCTION OR BREAKDOWN, grounding provides the path of least resistance for an electric current and reduces the risk of electric shock. This tool is equipped with an electric cord that has an equipment grounding conductor and a grounding plug. The plug MUST be plugged into a matching outlet that is properly installed and grounded in accordance with ALL local codes and ordinances.
DO NOT MODIFY THE PLUG PROVIDED. If it will not fit the outlet, have the proper outlet installed by a licensed electrician.
IMPROPER CONNECTION of the equipment grounding conductor can result in electric shock. The conductor with the green insulation (with or without yellow stripes) is the equipment grounding conductor. If repair or replacement of the electric cord or plug is necessary, DO NOT connect the equipment grounding conductor to a live terminal.
CHECK with a licensed electrician or service personnel if you do not completely understand the grounding instructions or whether the tool is properly grounded.
USE ONLY THREE-WIRE EXTENSION CORDS that have three-pronged plugs and outlets that accept the tool’s plug as shown in Fig. A. Repair or replace a damaged or worn cord immediately.
warning 2 CAUTION: In all cases, make certain the outlet in question is properly grounded. If you are not sure, have a licensed electrician check the outlet.
WARNING: This tool is for indoor use only. Do not expose to rain or use in damp locations.

AMPERAGEREQUIRED GAUGE FOR EXTENSION CORDS
25 ft50 It100 li.150
1.2 A18 gauge16 gauge16 gauge14 gunge

Make sure your extension cord is in good condition. When using an extension cord, be sure to use one heavy enough to carry the current your product will draw. An undersized cord will cause a drop in line voltage resulting in loss of power and overheating. The table below shows the correct size to be used according to cord length and nameplate ampere rating. When in doubt, use a heavier cord. The smaller the gauge number, the heavier the cord.
Make sure your extension cord is properly wired and in good condition. Always replace a damaged extension cord or have it repaired by a qualified person before using it.
Protect your extension cords from sharp objects, excessive heat, and damp/wet areas.
Use a separate electrical circuit for your tools. This circuit must not be less than a #12 wire and should be protected with a 15 A time-delayed fuse. Before connecting the motor to the power line, make sure the switch is in the OFF position and the electric current is rated the same as the current stamped on the motor nameplate. Running at a lower voltage will damage the motor.
WARNING: This tool must be grounded while in use to protect the operator from electric shock.

KNOW YOUR SCROLL SAW

WEN 3921 16-Inch Variable Speed Scroll Saw - Diagram 3WEN 3921 16-Inch Variable Speed Scroll Saw - Diagram 2

A – Blade Tension Knob
B – Arm Housing
C – Rubber Bearing Covers
D – Table
E – Sawdust Blower
F – Storage Area
G – Base
H – Bevel Scale and Pointer
I – Table/Bevel Lock Knob
J – Lower Blade Holder
K – Blade Guard Foot
L – Blade Guard Root Lock Knob
M – LED Light
N – Upper Blade Holder
O – Table Insert
P- Sawdust Collection Port
Q – ON/OFF Switch
R – Speed Control Knob
S – Table Adjusting Screw
T- Pinless Blade Holder

ASSEMBLY AND ADJUSTMENTS

UNPACKING
Carefully unpack the scroll saw and all of its parts. Compare them against the list below. Do not discard the carton or any packaging until the scroll saw is completely assembled.
CAUTION: do not lift the saw by the arm that holds the blade. The saw will be damaged.
WARNING: To avoid injury from accidental startups, turn the switch OFF and remove the plug from the power source outlet before making any adjustments.

WEN 3921 16-Inch Variable Speed Scroll Saw - fig 18

INCLUDES (Fig. 1)
A – Scroll saw with attached light
B – Extra pin blade

WEN 3921 16-Inch Variable Speed Scroll Saw - fig 17

STORAGE AREA (Fig. 2)
A convenient storage location for the extra blade can be found beneath the saw’s table.

ASSEMBLY AND ADJUSTMENTS

Prior to making adjustments, mount the scroll saw on a stable surface. See “Bench mounting the saw.”

ALIGN THE BEVEL INDICATOR (Fig. 3-6)
The level indicator has been factory adjusted. It should be rechecked prior to use for best operation.

  1. Remove the blade guard foot (1) using a Phillips head screwdriver (not included) to loosen the screw (2).
  2. Loosen the table bevel lock knob (3) and move the table until it is approximately at a right angle to the blade.
  3. Loosen the locking nut (5) on the table adjusting screw (6) under the table by turning it counter-clockwise. Lower the table adjusting screw by turning it clockwise.
  4. Use a combination square (7) to set the table exactly 90° to the blade (8). If there is space between the square and blade, adjust the table angle until the space is closed.
    WEN 3921 16-Inch Variable Speed Scroll Saw - fig 16
  5. Lock the table bevel lock knob under the table (3) to prevent movement.
  6. Tighten the adjusting screw under the table until the tip of the screw touches the table. Tighten the lock nut.
  7. Loosen the screw (4) holding the bevel scale pointer and position the pointer to 0°. Tighten the screw.
  8. Attach the blade guard foot (1) so the foot rests flat against the table. Tighten the screw (2) using a Phillips head screwdriver (not included).
    Note: Avoid setting the edge of the table against the top of the motor. This can cause excess noise when the saw is running.

WEN 3921 16-Inch Variable Speed Scroll Saw - fig 15

ASSEMBLY AND ADJUSTMENTS
BENCH MOUNTING THE SAW (Fig. 7-8)

Before operating the saw, it must be firmly mounted to a workbench or another rigid frame. Use the base of the saw to mark and pre-drill the mounting holes. If the saw is to be used in one location, permanently secure it to the work surface using wood screws if mounting to wood. Use bolts, washers, and nuts if mounting into metal. To reduce noise and vibration, install a soft foam pad (not supplied) between the scroll saw and the workbench.
Note: mounting hardware not included.

warning 2 WARNING – to reduce the risk of injury:
– When carrying the saw, hold it close to your body to avoid injury to your back. Bend your knees when lifting the saw.
– Carry the saw by the base. Do not carry the saw by the power cord.
– Secure the saw in a position where people cannot stand, sit, or walk behind it. Debris thrown from the saw could injure people standing, sitting, or walking behind it.
– Secure the saw on a firm, level surface where the saw cannot rock. Make sure there is adequate room for handling and properly supporting the workpiece.

WEN 3921 16-Inch Variable Speed Scroll Saw - fig 14

Blade guard foot adjustment (Fig. 7 and 8)
When cutting at angles, the blade guard foot should be adjusted so it is parallel to the table and rests flat above the workpiece.

  1. To adjust, loosen the screw (2), tilt the foot (1) so it is parallel to the table, and tighten the screw.
  2. Loosen the height adjustment knob (3) to raise or lower the foot until it just rests on top of the workpiece. Tighten the knob.

ADJUSTING THE DUST BLOWER (Fig. 9)

For best results, the dust blower tube (1) should be adjusted to direct air at both the blade and the work piece.

WEN 3921 16-Inch Variable Speed Scroll Saw - fig 13

SAWDUST COLLECTION PORT (Fig. 10 and 11)
This scroll saw allows a hose or vacuum accessory (not provided) to be connected to the dust chute (2). If excessive sawdust buildup occurs inside the base, use a wet/dry vacuum cleaner or manually remove sawdust by removing the screws (3) and metal plate on the left side of the saw. Reattach the metal plate and screws before starting the saw. This will keep your saw cutting efficiently.

WEN 3921 16-Inch Variable Speed Scroll Saw - fig 12

BLADE SELECTION (Fig. 12)
This scroll saw accepts 5” length pin end and pinless blades, with a wide variety of blade thicknesses and widths. The type of material and intricacies of cutting operations will determine the number of teeth per inch. Always select the narrowest blades for intricate curve cutting and the widest blades for straight and large curve cutting operations. The following table represents suggestions for various materials. Use this table as an example, but with practice, personal preference will be the best selection method. When choosing a blade, use very fine, narrow blades to scroll cut in thin wood 1/4” thick or less. Use wider blades for thicker materials but this will reduce the ability to cut tight curves. A smaller blade width can cut circles with smaller diameters. Note: Thinner blades will have more possibilities for blade deflection when cutting angles are not perpendicular to the table.WEN 3921 16-Inch Variable Speed Scroll Saw - fig 11

TEETH PER INCHBLADE WIDTHBLADE THICKNESSBLADE PMMATERIAL CUT
10 to 15.11-.018-500 to 1200
SPM
Medium turns on 1/4″ to 1-3/4″ wood, soft metal, hardwood
15 to 28.055- to .11 –.01 to .018″800 to 1700
SPM
Sinai! turns on 1/8″ to 1-1/2″ wood, soft metal, hardwood

BLADE CARE
To maximize the life of your scroll saw blades:

  1. Do not bend blades when installing.
  2. Always set proper blade tension.
  3. Use the right blade (see instruction on replacement blade packaging for proper use).
  4. Feed the work correctly into the blade.
  5. Use thin blades for intricate cutting.

warning 2 CAUTION: Any and all servicing should be performed by a qualified service center.

BLADE REMOVAL AND INSTALLATION (Fig. 13 to 15)

warning 2 WARNING: To prevent personal injury, always turn saw OFF and disconnect the plug from the power source before changing blades or making adjustments.

This saw uses pinned and pinless blades. Pinned blades are thicker for stability and for faster assembly. They provide faster cutting on a variety of materials.
Note: When installing pinned blades, the slot on the blade holder must be slightly wider than the thickness of the blade. After the blade is installed, the blade tension mechanism will keep it in place.
WEN 3921 16-Inch Variable Speed Scroll Saw - fig 10

  1. To remove the blade, loosen the tension on it by lifting up the blade tension lever. Turn the lever counterclockwise to loosen the blade holder if necessary.
  2. Remove the table insert. Carefully pry up on the table insert to remove.
  3. Push down on the upper blade holder to remove the blade from the holder (2). Remove the blade from the lower blade holder (3).
    WEN 3921 16-Inch Variable Speed Scroll Saw - fig 9CAUTION: Install the blade with the teeth pointing downward.
  4. To install the blade, hook the blade in the recess of the lower blade holder (3).
  5. While pushing down on the upper blade holder, insert the blade into the slot of the holder.
  6.  Move the blade tension lever down and make sure the blade pin is properly positioned in the blade holders.
  7. Adjust the blade to the desired tension. Turning the blade tension knob clockwise tightens the blade and turning the knob counterclockwise loosens the blade.
  8. Place the table insert back into place.

WEN 3921 16-Inch Variable Speed Scroll Saw - fig 8

ADJUSTING THE BLADE DIRECTION (Fig. 16 & 17)
The WEN Scroll Saw accepts pinned blades in two different positions to accommodate a wider variety of workpieces. Notice the two various slots for pinned blades that appear
on the head of the saw (Fig. 16).
WEN 3921 16-Inch Variable Speed Scroll Saw - fig 8Pinned blades can be placed in either of the two slots, changing the direction of the blade by 90 degrees. A coinciding slot exists for each holder underneath the plate.
INSTALLING PINLESS BLADE (Fig. 18 & 19)

  1. Remove the existing blade and table insert (see Blade Removal and Installation).
  2. To install the pinless blade, loosen the thumb screw on the lower blade attachment.
    WEN 3921 16-Inch Variable Speed Scroll Saw - fig 7
  3. Install the blade into the lower blade attachment and tighten the thumb screw. Hook the lower blade attachment onto the curve of the bottom blade holder found underneath the table (1).
  4. Place the insert back into the table after carefully inserting the blade through the table insert slot and the pilot hole of the workpiece.
  5. Insert the blade into the upper blade attachment. Tighten the upper thumb screw to secure the blade.
    WEN 3921 16-Inch Variable Speed Scroll Saw - fig 6
  6. Hook the upper blade attachment onto the top curve of the upper blade holder (2).
  7. Move the blade tension lever down and make sure the blade attachments are properly secured and tensioned onto the machine.
    WEN 3921 16-Inch Variable Speed Scroll Saw - fig 5

OPERATION

RECOMMENDATIONS FOR CUTTING
A scroll saw is basically a curve-cutting machine. It can also be used for straight cutting and beveling or angle cutting operations. Please read and understand the following items before attempting to use the saw.

  1. When feeding the workpiece into the blade do not force it against the blade. This could cause blade deflection. Allow the saw to cut the material by guiding the workpiece into the blade as it cuts.
  2. The blade teeth cut material ONLY on the down stroke.
  3. Guide the wood into the blade slowly because the teeth of the blade are very small and remove wood only on the down stroke.
  4. There is a learning curve for each person using this saw. During that period of time, it is expected that some blades will break until you learn how to use the saw.
  5. Best results are achieved when cutting wood one inch thick or less.
  6. When cutting wood thicker than one inch, guide the wood slowly into the blade and take extra care not to bend or twist the blade while cutting in order to maximize blade life.
  7. Teeth on the scroll saw blades wear out and the blades must be replaced frequently for best cutting results. Scroll saw blades generally stay sharp for 1/2 hour to 2 hours of cutting.
  8. To get accurate cuts, be prepared to compensate for the blade’s tendency to follow the wood grain.
  9. This scroll saw is primarily designed to cut wood or wood products. For cutting precious and non-ferrous metals, the variable control switch must be set at very slow speeds.
  10. When choosing a blade, use very fine, narrow blades to scroll cut in thin wood 1/4” thick or less. Use wider blades for thicker materials. This, however, will reduce the ability to cut tight curves.
  11.  Blades wear down faster when cutting plywood or very abrasive particle board. Angle cutting in hardwoods also wears blades down faster.

OPERATION

ON/OFF & SPEED CONTROL SWITCH (Fig. 20)
Always wait for the saw to come to a complete stop before restarting.

  1. To turn the saw on, flip the ON/OFF switch to ON (2). When first starting the saw, it is best to move the speed control knob (1) to the middle-speed position.
  2. Adjust the blade speed to the desired setting between 400 to 1600 strokes per minute (SPM). Turning the control knob clockwise increases speed; turning it counterclockwise reduces speed.
    3. To turn the saw off, flip the ON/OFF switch back to OFF (2) in. Note: You can lock the scroll saw by removing the tip of the switch. Just pry off the switch lock with your fingernails to prevent accidental operation.

WARNING: To avoid injury from accidental start-ups, always turn the switch OFF and unplug the scroll saw before moving the tool, replacing the blade, or making adjustments.
FREEHAND CUTTING (Fig. 21)

  1. Lay out desired design or secure design to the workpiece.
  2. Raise the blade guard foot (1) by loosening the height adjustment knob (2).
  3. Position the workpiece against the blade and place the blade guard foot against the top surface of the workpiece.
  4. Secure the blade guard foot (1) by tightening the height adjustment knob (2).
  5. Remove the work piece from the blade prior to turning the scroll saw ON.
    CAUTION: In order to avoid uncontrollable lifting of the workpiece and to reduce blade breakage, do not turn the switch on while the workpiece is against the blade.
  6. Slowly feed the workpiece into the blade by guiding and pressing the workpiece down against the table.
    CAUTION: Do not force the leading edge of the workpiece into the blade. The blade will deflect, reducing the accuracy of the cut, and may break.
  7. When the cut is complete, move the trailing edge of the workpiece beyond the blade guard foot. Turn the switch OFF.

WEN 3921 16-Inch Variable Speed Scroll Saw - fig 4

ANGLE CUTTING (BEVELING) (Fig. 22)

  1. The layout or secure design to the workpiece.
  2. Move the blade guard foot to the highest position by loosening the height adjustment knob (1). Retighten.
  3. Tilt the table to the desired angle by loosening the table bevel lock handle (2). Move the table to the proper angle using the degree scale and the pointer (3).
  4. Tighten the table bevel lock handle (2).
  5.  Loosen the blade guard screw, and tilt the blade guard to the same angle as the table. Retighten the blade guard screw.
  6. Position the workpiece on the right side of the blade. Lower the blade guard foot against the surface by loosening the height adjustment knob. Retighten.
  7.  Follow steps 5 to 7 under Freehand cutting.
    WEN 3921 16-Inch Variable Speed Scroll Saw - fig 3

INTERIOR CUTTING (Fig. 23
WEN 3921 16-Inch Variable Speed Scroll Saw - fig 2

  1. Lay out the design on the workpiece. Drill a 1/4” hole in the workpiece.
  2. Remove the blade. See Blade removal and installation.
  3. Place the workpiece on the saw table with the hole in the workpiece over the access hole in the table.
  4. Install a blade through the hole in the workpiece.
  5. Follow steps 3-7, under Freehand cutting.
  6. When finished making the interior scroll cuts simply turn the scroll saw OFF. Unplug the saw before removing the blade from the blade holder. Remove the work piece from the table.

MAINTENANCE

WARNING: Always turn the switch OFF and unplug the power cord from the outlet before maintaining or lubricating the scroll saw.
To ensure that the wood glides smoothly across the work surface, periodically apply a coat of paste wax (sold separately) to the surface of the worktable. If the power cord is worn out or damaged in any way, replace it immediately. Do not attempt to oil the motor bearings or service the motor’s internal parts.

LUBRICATION (Fig. 25)
Lubricate the arm bearings after every 50 hours of use.

  1. Turn the saw on its side and remove the cover.
  2. Squirt a generous amount of SAE 20 oil (lightweight motor oil, sold separately) around the shaft and bearing.
  3. Let the oil soak in overnight.
  4. Repeat the above procedure for the opposite side of the saw.
    WEN 3921 16-Inch Variable Speed Scroll Saw - fig

BLADES
To maximize the life of your scroll saw blades:

  1. Do not bend blades when installing.
  2. Always set proper blade tension.
    3. Use the right blade (see instructions on replacement blade packaging for proper use).
    4. Feed the work correctly into the blade.
    5. Use thin blades for intricate cutting.
    CAUTION: Any and all servicing should be performed by a qualified service center.

EXPLODED VIEW & PARTS LIST

WEN 3921 16-Inch Variable Speed Scroll Saw - Diagram

ItemStock #Description
13920B-001Screw M5x8
23920B-002Screw ST4.2×10
33920B-003Side Cover
43920B-004Nut M6
53920B-005Spring Washer M6
63920B-006Base
73920B-007Oil Cap
8A3920C-008ALeft Arm Housing
8B3920C-008BRight Arm Housing
93920B-009Tension Bolt Assembly
103920B-010Extension Spring
113920B-011Pressure Plate
123920B-012Spring Washer M4
133920B-013Screw M4X10
143920C-013Lower Arm
153920C-014Upper Arm
163920C-015Arm Bearing
173920C-016Blast Pipe
183920B-018Screw M5x6
193920B-019Light Assembly
203920B-020Spring Washer M5
213920B-021Screw M5x35
223920B-022Screw M4x6
233920B-023Bellows Cap
243920B-024Screw M5x28
253920B-025Table Lock Knob
263920B-026Switch Fixing Board
273920B-027Switch
283920B-028Bellows
293920B-029Fixing Plate
303920B-030Bolt M6x20
313920C-030Upper Blade Support
323920B-032Washer M4
333920B-033Screw M4x20
343920C-034Support Cushion
353920B-076Blade 15TPI
363920B-036Screw M5x25
373920B-037Big Cushion
383920B-038Eccentricity Connector
393920B-039Bearing 625Z (80025)
403920B-040Nut M5
413920B-041Clamping Board
423920B-042Screw ST4.2×9.5
433920B-043Washer
443920B-044Screw M5x16
453920C-044Lower Blade Support
463920B-046Drop Foot Lock Knob
473920B-047Drop Foot Fixing Pole
483920B-048Screw M5x30
493920B-049PCB
503920B-050Drop Foot
523920B-052Screw M6x10
533920B-053PVC Pipe
543920B-054Big Washer M6
553920B-055Screw M6x40
563920B-056Bolt M6x16
573920B-057Washer M6
583920B-058Spring
593920B-059Screw M6x25
603920B-060Work Table Bracket
613920B-061Pointer
623920B-062Bevel Scale
633920B-063Work Table
643920B-064Work Table Insert
653920B-065Speed Adjusting Knob
663920B-066Screw M5x6
673920B-067Power Cord
683920B-068Screw M4x8
693920B-069Screw M8x12
703920B-070Eccentric Wheel
713920B-071Motor
723920B-072Switch Box
733920B-073Cord Clamp
743920B-074Screw
753920B-075Potentiometer
763920B-076-2Blade 18TPI Pinless
773920B-077Screw M4x10
783920B-078Screw M6x10
803920B-080Foot
813920B-081Wire Clip 1
823920B-082Wire Clip 2
833920B-083Screw M4x8
843920B-084Transformer Box
853920B-085Circuit board
863920B-086Screw ST2.9×6.5
873920B-087Cord Bushing 1
883920B-088Cord Bushing 2
893920B-019LED Assembly
913920B-091Tool Box
923920B-092Bolt M8x20
933920B-093Bolt M6x80
943920B-094Nut M4
953920C-095Wrench S3
963920C-096Wrench S2.5
973920C-097Blade Adaptor
983920C-098Set Screw M5x8
993920B-076-1Blade 18TPI Pinned
1003920C-100Adaptor Location Screw

LIMITED TWO-YEAR WARRANTY

WEN Products is committed to building tools that are dependable for years. Our warranties are consistent with this commitment and our dedication to quality.
LIMITED WARRANTY OF WEN CONSUMER POWER TOOLS PRODUCTS FOR HOME USE GREAT LAKES TECHNOLOGIES, LLC (“Seller”) warrants to the original purchaser only, that all WEN consumer power tools will be free from defects in material or workmanship for a period of two (2) years from the date of purchase. Ninety days for all WEN products, if the tool is used for professional use.
SELLER’S SOLE OBLIGATION AND YOUR EXCLUSIVE REMEDY under this Limited Warranty and, to the extent permitted by law, any warranty or condition implied by law, shall be the repair or replacement of parts, without charge, which are defective in material or workmanship and which have not been misused, carelessly handled, or misrepaired by persons other than Seller or Authorized Service Center. To make a claim under this Limited Warranty, you must make sure to keep a copy of your proof of purchase that clearly defines the Date of Purchase (month and year) and the Place of Purchase. The place of purchase must be a direct vendor of Great Lakes Technologies, LLC. Third-party vendors such as garage sales, pawn shops, resale shops, or any other secondhand merchant void the warranty included with this product.
Contact  echsupport@wenproducts.com or 1-800-2321195 to make arrangements for repairs and transportation.
When returning a product for warranty service, the shipping charges must be prepaid by the purchaser. The product must be shipped in its original container (or an equivalent), properly packed to withstand the hazards of shipment. The product must be fully insured with a copy of the warranty card and/or the proof of purchase enclosed.
There must also be a description of the problem in order to help our repairs department diagnose and fix the issue. Repairs will be made and the product will be returned and shipped back to the purchaser at no charge.
THIS LIMITED WARRANTY DOES NOT APPLY TO ACCESSORY ITEMS THAT WEAR OUT FROM REGULAR USAGE OVER TIME INCLUDING BELTS, BRUSHES, BLADES, ETC. ANY IMPLIED WARRANTIES SHALL BE LIMITED IN DURATION TO TWO (2) YEARS FROM DATE OF PURCHASE. SOME STATES IN THE U.S., AND SOME CANADIAN PROVINCES DO NOT ALLOW LIMITATIONS ON HOW LONG AN IMPLIED WARRANTY LASTS, SO THE ABOVE LIMITATIONS MAY NOT APPLY TO YOU.
IN NO EVENT SHALL THE SELLER BE LIABLE FOR ANY INCIDENTAL OR CONSEQUENTIAL DAMAGES (INCLUDING BUT NOT LIMITED TO LIABILITY FOR LOSS OF PROFITS) ARISING FROM THE SALE OR USE OF THIS PRODUCT. SOME STATES IN THE U.S. AND SOME CANADIAN PROVINCES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF INCIDENTAL OR CONSEQUENTIAL DAMAGES, SO THE ABOVE LIMITATION  OR EXCLUSION MAY NOT APPLY TO YOU.
THIS LIMITED WARRANTY GIVES YOU SPECIFIC LEGAL RIGHTS, AND YOU MAY ALSO HAVE OTHER RIGHTS WHICH VARY FROM STATE TO STATE IN THE U.S., PROVINCE TO PROVINCE IN CANADA, AND FROM COUNTRY TO COUNTRY. THIS LIMITED WARRANTY APPLIES ONLY TO PORTABLE ELECTRIC TOOLS, BENCH POWER TOOLS, OUTDOOR POWER EQUIPMENT, AND PNEUMATIC TOOLS SOLD WITHIN THE UNITED STATES OF AMERICA, CANADA, AND THE COMMONWEALTH OF PUERTO RICO. FOR WARRANTY COVERAGE WITHIN OTHER COUNTRIES, CONTACT THE WEN CUSTOMER SUPPORT LINE.

Documents / Resources

WEN 3921 16-Inch Variable Speed Scroll Saw [pdf] Instruction Manual
3921, 16-Inch Variable Speed Scroll Saw, 3921 16-Inch Variable Speed Scroll Saw

References

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