Operating Instructions and Parts Manual
JBG-W Series Grinder with Wire Wheel
Models JBG-6W, JBG-8W
JET
427 New Sanford Road
LaVergne, Tennessee 37086 Part No. M-577126
Ph.: 800-274-6848 Edition 3 11/2018
www.jettools.com Copyright © 2018 JET
1
1.0 IMPORTANT SAFETY
INSTRUCTIONS
WARNING – To reduce risk of injury:
1. Read and understand the entire owner's
manual before attempting assembly or
operation.
2. Read and understand the warnings posted on
the machine and in this manual. Failure to
comply with all of these warnings may cause
serious injury.
3. Replace warning labels if they become
obscured or removed.
4. This bench grinder is designed and intended for
use by properly trained and experienced
personnel only. If you are not familiar with the
proper and safe operation of a bench grinder,
do not use until proper training and knowledge
have been obtained.
5. Do not use this bench grinder for other than its
intended use. If used for other purposes, JET
disclaims any real or implied warranty and holds
itself harmless from any injury that may result
from that use.
6. Always wear protective eye wear when
operating machinery. Eye wear shall be impact
resistant, protective safety glasses with side
shields which comply with ANSI Z87.1
specifications. Use of eye wear which does not
comply with ANSI Z87.1 specifications could
result in severe injury from breakage of eye
protection. (Everyday eyeglasses only have
impact resistant lenses; they are NOT safety
glasses.) Use the grinder’s eye shields and
spark guards. Also use face or dust mask if
cutting operation is dusty.
7. Wear proper apparel. Do not wear loose
clothing, neckties, rings, bracelets, or other
jewelry which may get caught in moving parts.
Non-slip footwear is recommended. Wear
protective hair covering to contain long hair.
8. Wear protective clothing such as apron or
safety shoes, where the grinding activity
presents a hazard to the operator.
9. Wear ear protectors (plugs or muffs) if sound
exceeds safe levels.
10. Do not operate this machine while tired or under
the influence of drugs, alcohol or any
medication.
11. Make certain the switch is in the OFF position
before connecting the machine to the power
supply.
12. Make certain the machine is properly grounded.
13. Make all machine adjustments or maintenance
with the machine unplugged from the power
source.
14. Remove adjusting keys and wrenches. Form a
habit of checking to see that keys and adjusting
wrenches are removed from the machine
before turning it on.
15. Keep safety guards in place at all times when
the machine is in use. If removed for
maintenance purposes, use extreme caution
and replace the guards immediately after
completion of maintenance.
16. Check damaged parts. Before further use of the
machine, a guard or other part that is damaged
should be carefully checked to determine that it
will operate properly and perform its intended
function. Check for alignment of moving parts,
binding of moving parts, breakage of 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.
17. Provide for adequate space surrounding work
area and non-glare, overhead lighting.
18. Keep the floor around the machine clean and
free of scrap material, oil and grease.
19. Keep visitors a safe distance from the work
area. Keep children away.
20. Make your workshop child proof with padlocks,
master switches or by removing starter keys.
21. Give your work undivided attention. Looking
around, carrying on a conversation and “horseplay” are careless acts that can result in serious
injury.
22. Keep proper footing and balance at all times so
that you do not fall into or lean against the
grinding wheel or other moving parts. Do not
overreach or use excessive force to perform
any machine operation.
23. Disconnect grinder before servicing and before
changing wheels.
24. Use recommended accessories. The use of
improper accessories may cause risk of injury
to persons.
25. Turn off the machine before cleaning. Use a
brush to remove chips or debris — do not use
bare hands.
26. Never leave the grinder running unattended.
Turn power off and do not leave machine until
wheels come to a complete stop.
2
27. Remove loose items and unnecessary work
pieces from the area before starting the grinder.
28. Don’t use in dangerous environment. Don’t use
power tools in damp or wet location, or expose
them to rain. Don’t use this grinder in a
flammable environment. Keep work area well
lighted.
29. Keep work area clean. Cluttered areas and
benches invite accidents.
30. Use right tool. Don't force tool or attachment to
do a job for which it was not designed.
31. Use proper extension cord. 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. Sect. 6.2, Table 2 shows the
correct size to use depending on cord length
and nameplate ampere rating. If in doubt, use
the next heavier gage. The smaller the gage
number, the heavier the cord.
32. Maintain tools with care. Keep tools sharp and
clean for best and safest performance. Follow
instructions for lubricating and changing
accessories.
33. Never stand on tool. Serious injury could occur
if the tool is tipped or if the cutting tool is
unintentionally contacted.
34. Direction of feed. Feed work into a blade or
cutter against the direction of rotation of the
blade or cutter only.
35. Do not overtighten wheel nut.
36. Frequently clean grinding dust from around and
beneath grinder.
37. Use grinding wheels suitable for speed of
grinder.
38. Inspect abrasive wheels for cracks or other
forms of damage. Perform a “ring test” to check
wheel integrity. Do not use a faulty or damaged
wheel.
39. Verify that maximum RPM of abrasive or wire
wheel is compatible with speed of grinder. Do
not remove the blotter (label) from either side of
a grinding wheel.
40. Allow machine to reach full RPM before starting
the grinding operation.
41. Do not crowd the work so that the wheel slows.
42. Tool rest should be adjusted to approximately
1/16” from wheel surface.
43. Do not grind on the side of a wheel; do all work
on the grinding face or edge near the tool rest.
44. Do not grind aluminum or magnesium on the
grinding wheel, as these may pose a fire/safety
hazard.
45. Use only the flanges that are furnished with the
grinder.
46. Secure work. Use clamps or a vise to hold work
when practical. It’s safer than using your hand
and it frees both hands to operate tool.
47. Reduce the risk of unintentional starting. Make
sure switch is in OFF position before plugging
in.
48. Allow wire brushes to run at operating speed for
at least one minute before using wheel. During
this time no one is to stand in front of or in line
with the brush.
WARNING: This product can expose you to
chemicals including lead and cadmium which
are known to the State of California to cause
cancer and birth defects or other reproductive
harm, and phthalates which are known to the
State of California to cause birth defects or other
reproductive harm. For more information go to
http://www.p65warnings.ca.gov.
WARNING: Some dust, fumes and gases
created by power sanding, sawing, grinding,
drilling, welding and other construction activities
contain chemicals known to the State of
California to cause cancer and birth defects or
other reproductive harm. Some examples of
these chemicals are:
lead from lead based paint
crystalline silica from bricks, cement and
other masonry products
arsenic and chromium from chemically
treated lumber
Your risk of exposure varies, depending on how
often you do this type of work. To reduce your
exposure to these chemicals, work in a wellventilated area and work with approved safety
equipment, such as dust masks that are
specifically designed to filter out microscopic
particles. For more information go to
http://www.p65warnings.ca.gov/ and http://www.
p65warnings.ca.gov/ wood.
- - SAVE THESE INSTRUCTIONS - -
3
2.0 Table of contents
Section Page
1.0 IMPORTANT SAFETY INSTRUCTIONS ....................................................................................................... 2
2.0 Table of contents ............................................................................................................................................ 4
3.0 About this manual .......................................................................................................................................... 5
4.0 Specifications for JBG-6W, JBG-8W Bench Grinders .................................................................................... 6
4.1 Mounting hole dimensions .......................................................................................................................... 7
5.0 Setup and assembly ....................................................................................................................................... 8
5.1 Unpacking .................................................................................................................................................. 8
5.2 Carton contents .......................................................................................................................................... 8
5.3 Tools required for assembly ....................................................................................................................... 8
5.4 Securing the grinder ................................................................................................................................... 9
5.5 Assembling eye shield brackets to spark guards ....................................................................................... 9
5.6 Installing spark guard/bracket .................................................................................................................... 9
5.7 Eye shield ................................................................................................................................................... 9
5.8 Tool rest ..................................................................................................................................................... 9
5.9 Dust port ................................................................................................................................................... 10
6.0 Electrical connections .................................................................................................................................. 10
6.1 GROUNDING INSTRUCTIONS ............................................................................................................... 10
6.2 Extension cords ........................................................................................................................................ 10
7.0 Operation ..................................................................................................................................................... 11
7.1 On/Off Switch ........................................................................................................................................... 11
7.2 Precautions .............................................................................................................................................. 11
8.0 Adjustments ................................................................................................................................................. 11
8.1 Eye Shield Tilt Adjustment ....................................................................................................................... 11
8.2 Spark Guard ............................................................................................................................................. 11
8.3 Tool Rest .................................................................................................................................................. 12
9.0 User-maintenance ........................................................................................................................................ 12
9.1 Ring Test .................................................................................................................................................. 12
9.2 Care of Grinding Wheels .......................................................................................................................... 12
9.3 Changing Wheels ..................................................................................................................................... 12
9.4 Wheel balancing ....................................................................................................................................... 13
9.5 Dressing the wheels ................................................................................................................................. 13
9.6 Cleaning ................................................................................................................................................... 14
9.7 Lubrication ................................................................................................................................................ 14
9.8 Additional servicing .................................................................................................................................. 14
10.0 Troubleshooting JBG-6W, JBG-8W Bench Grinders ................................................................................. 15
11.0 Optional accessories .................................................................................................................................. 17
12.0 Replacement Parts ..................................................................................................................................... 17
12.1.1 JBG-W series Grinder with Wire Wheel – Exploded View .................................................................. 18
12.1.2 JBG-6W, JBG-8W Grinders – Parts List ............................................................................................. 19
13.0 Wiring Diagram for JBG-6W, JBG-8W Grinders ........................................................................................ 21
14.0 Warranty and service ................................................................................................................................. 22
4
3.0 About this manual
This manual is provided by JET, covering the safe operation and maintenance procedures for a JET Model JBGW series Bench Grinder with Wire Wheel. This manual contains instructions on installation, safety precautions,
general operating procedures, maintenance instructions and parts breakdown. This tool has been designed and
constructed to provide consistent, long-term operation if used in accordance with the instructions set forth in this
document.
If there are questions or comments, please contact your local supplier or JET. JET can also be reached at our
web site: www.jettools.com.
Retain this manual for future reference. If the machine transfers ownership, the manual should accompany it.
Read and understand the entire contents of this manual before attempting assembly or
operation! Failure to comply may cause serious injury!
Register your product using the mail-in card provided, or register online:
http://www.jettools.com/us/en/service-and-support/product-registration/
Familiarize yourself with the following safety notices used in this manual:
This means that if precautions are not heeded, it may result in minor injury and/or possible
machine damage.
injury.
This means that if precautions are not heeded, it may result in serious, or possibly even fatal,
5
4.0 Specifications for JBG-6W, JBG-8W Bench Grinders
Table 1
Stock number
Model number JBG-6W JBG-8W
Motor and Electricals
Motor type induction, capacitor start, centrifugal switch
Horsepower 1/2 HP 1 HP
Phase single
Voltage 115 V
Cycle 60 Hz
Listed FLA (full load amps)
Start capacitor 100MFD 125VAC 200MFD 125VAC
Motor speed 3,450 RPM
On/off switch rocker style toggle style
Power transfer
Power cord SJT 18AWG x 3C, 300V, 6 ft. SJT 16AWG x 3C, 300V, 6 ft.
Power plug installed 5-15P, 125V/15A
Recommended circuit size 1 15A
Sound emission 2 75dB at 3ft. without load
Arbor and wheels
Arbor diameter 1/2 in. 5/8 in.
Grinding wheel size (O.D. x width x bore) 6 x 3/4 x 1/2 in. 8 x 1 x 5/8 in.
Grinding wheel provided 36 grit, aluminum oxide
Wheel bore 1/2 in. 5/8 in.
Wire wheel size (O.D. x width x bore) 6 x 1/2 x 1/2 in. 8 x 1/2 x 5/8 in.
Wire wheel material Steel wire with plated copper
Wheel flange diameter 2 in. (50.8 mm) 2-3/4 in. (70 mm)
Wheel speed 3,450 RPM
Arbor nut maximum tightening torque 20 lbf-ft (270kgf-cm)
Tool rest distance to wheel adjustable
Main materials
Arbor steel
Base cast iron
Motor housing cast iron
Inner wheel guard cast iron
Outer wheel guard aluminum
Wheel flanges sheet metal
Tool rest cast iron
Eye shield clear polycarbonate
Spark guard steel
Knob polymide
Dust/swarf collection
Dust port outside diameter 2 in. (50.8 mm)
Recommended minimum extraction volume 350 CFM
General dimensions
Footprint (LxW) 7-5/8 x 5-1/2 in.
Overall dimensions assembled (LxWxH) 13-1/2 x 11 x 10-5/8 in.
Shipping dimensions (LxWxH)
19-11/16 x 12-3/16 x 11-11/16 in.
577126 577128
5.0 A 8.0 A
Direct drive
(194 x 140 mm)
(343 x 280 x 270 mm)
22-1/4 x 14-3/8 x 13-1/8 in.
(500 x 310 x 297 mm)
8-7/16 x 6-5/16 in.
(214 x 160 mm)
18-1/2 x 13 x 12 in.
(469 x 330 x 305 mm)
(565 x 365 x 333 mm)
6
Weights
Net weight (approx.) 32 lb. (14.40 kg) 54 lb. (24.56 kg)
Shipping weight (approx.) 35 lb. (15.85 kg) 58 lb. (26.50 kg)
1
subject to local and national electrical codes.
2
The specified values are emission levels and are not necessarily to be seen as safe operating levels. As workplace
conditions vary, this information is intended to allow the user to make a better estimation of the hazards and risks
involved only.
L = length, W = width, H = height
O.D. = outside diameter
CFM = cubic feet per minute
The specifications in this manual were current at time of publication, but because of our policy of continuous
improvement, JET reserves the right to change specifications at any time and without prior notice, without incurring
obligations.
4.1 Mounting hole dimensions
Figure 4-1: hole centers
7
5.0 Setup and assembly
5.1 Unpacking
Separate all parts from the packing material. Check
each part against sect. 5.2, Carton contents, and
make certain that all items are accounted for.
(Check grinder first to verify if any parts have been
pre-mounted.) Notify your dealer or JET if parts are
missing or there is shipping damage. Do not discard
packing material until grinder is assembled and
operating properly.
5.2 Carton contents
Refer to Figure 5-1.
1 Bench Grinder with wheels (not shown)
1 Spark guard, left – A
2 Lock knobs – B
1 Spark guard, right – C
1 Eye shield bracket, left – D
2 Truss head screws, 1/4 x 1/2 – E
1 Eye shield bracket, right – F
2 Eye shield plates – G
4 Hex cap screws, 5/16 x 3/4 – H
4 Flat washers, 5/16 – J
4 Pan head screws, 3/16 x 3/8 – K
4 Hex cap screws 1/4 x 3/8 – L
6 Flat Washers 1/4 – M
2 Lock Washers 1/4 – N
1 Tool rest, left – O
1 Tool rest, right – P
2 Eye shields – R
1 Operating Instructions and Parts Manual
1 Product registration card
Chipped or cracked wheels can
break up and cause serious damage to grinder
and/or severe injury to operator. Regularly
inspect wheels for damage.
5.3 Tools required for assembly
10mm and 12mm, or adjustable, wrench
#1 or #2 cross-point (Phillips) screwdriver
The JBG-W series Grinder requires only assembly
of eye shields and tool rests. Additional tools may
be needed for fastening the grinder to a workbench
or stand. For your safety, do not plug the grinder into
a power source until all assembly and adjustments
are complete.
Be sure that grinder is
unplugged and power switch is in OFF position.
Do not plug in grinder to power until it is
inspected for shipping damage and fully
assembled. Failure to comply may cause
serious injury.
Do not operate grinder without
all guards and shields in place and in working
order. Failure to comply may cause serious
injury.
8
Figure 5-1: carton contents
5.4 Securing the grinder
To prevent the grinder from moving during
operation, it should be securely mounted to a work
surface or grinder stand. Fasteners for mounting are
not included with the grinder.
1. Align the mounting holes on grinder with
predrilled holes in a bench or grinder stand.
Figure 4-1 shows hole centers for mounting.
2. Insert 3/8-in. (or 10mm) bolts through the holes
and tighten, using washers and nuts.
An optional pedestal stand (not included) is
available from JET for your grinder. See sect. 11.0.
wears down, the spark guard must be readjusted to maintain this 1/16" distance.
3. Install right spark guard and mounting bracket
in similar manner.
5.7 Eye shield
Refer to Figure 5-3.
The eye shields are identical and will fit on either
side of grinder.
Insert two 3/16 x 3/8 pan head screws (K) through
bracket, eye shield (R), and plate (G) which contains
threaded mounting holes. Tighten screws.
5.5 Assembling eye shield brackets
to spark guards
Refer to Figure 5-2.
Note: Spark guards (A/C) and eye shield brackets
(D/F) are marked L for left side assembly and R for
right side assembly.
1. Assemble left spark guard and eye shield
bracket using Figure 5-2 as a guide. Make sure
spark guard and bracket are marked L.
2. Assemble right side components in similar
manner.
5.8 Tool rest
Refer to Figure 5-3.
There is a left and a right tool rest. Refer to Figure
5-3 to ensure proper orientation.
1. Install left tool rest (O) by inserting two 5/16 x
3/4 hex cap screws (H) through two 5/16 flat
washers (J), and tool rest, into wheel housing.
2. The tool rest should be adjusted to within 1/16"
of the grinding wheel or other accessories being
used. As the wheel wears down, the tool rest
must be readjusted to maintain a maximum
1/16" clearance.
3. Assemble right tool rest in similar manner.
Figure 5-2: bracket to spark guard
5.6 Installing spark guard/bracket
Refer to Figure 5-3.
1. Install left spark guard and mounting bracket
assembly to left wheel housing with two 1/4" x
3/8” hex cap screws (L) and two 1/4" flat
washers (M).
2. The spark guard (A
within 1/16" of the grinding wheel surface or
other accessory being used. As the wheel
) should be adjusted to
1
Figure 5-3: guard and tool rest
9
5.9 Dust port
It is recommended that a metalworking dust
collection system be connected to the grinder’s dust
port, using a 2-in. diameter hose with hose clamp
(not provided).
6.0 Electrical connections
Electrical connections must be
made by a qualified electrician in compliance
with all relevant codes. This tool must be
properly grounded. Failure to comply may result
in serious injury.
The models JBG-6W and JBG-8W Bench Grinders
are prewired for 115V power, and are supplied with
a plug designed for use on a circuit with a grounded
outlet that looks like the one pictured in A, Figure 6-
1.
Before connecting to power source, be sure switch
is in off position.
It is recommended that the grinder be connected to
a 15 amp circuit with circuit breaker or fuse. Local
codes take precedence over recommendations.
Check with a qualified
electrician or service personnel if the grounding
instructions are not completely understood, or if
in doubt as to whether the tool is properly
grounded. Failure to comply may cause serious
or fatal injury.
Use only 3-wire extension cords that have 3-prong
grounding plugs and 3-pole receptacles that accept
the tool's plug.
Repair or replace damaged or worn cord
immediately.
2. Grounded, cord-connected tools intended for use
on a supply circuit having a nominal rating less than
150 volts:
This tool is intended for use on a circuit that has an
outlet that looks like the one illustrated in A, Figure
6-1. An adapter, shown in B and C, may be used to
connect this plug to a 2-pole receptacle as shown in
B if a properly grounded outlet is not available. The
temporary adapter should be used only until a
properly grounded outlet can be installed by a
qualified electrician. The green-colored rigid ear,
lug, and the like, extending from the adapter must
be connected to a permanent ground such as a
properly grounded outlet box. In Canada, the use of
a temporary adaptor is not permitted by the
Canadian Electrical Code, C22.1.
Figure 6-1: plug configuration
6.1 GROUNDING INSTRUCTIONS
1. All Grounded, Cord-connected Tools:
This tool must be grounded. In the event of a
malfunction or breakdown, grounding provides a
path of least resistance for electric current to reduce
the risk of electric shock. This tool is equipped with
an electric cord having 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 qualified
electrician.
Improper connection of the equipment-grounding
conductor can result in a risk of electric shock. The
conductor with insulation having an outer surface
that is green 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.
6.2 Extension cords
The use of extension cords is discouraged. Try to
position equipment near the power source. If an
extension cord becomes necessary, use only threewire extension cords that have three-prong
grounding type plugs and three-prong receptacles
that accept the tool's plug. Replace or repair
damaged or worn cord immediately.
Make sure your extension cord is good condition,
and is 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.
Table 2 shows the correct size to use depending on
cord length and nameplate ampere rating. If in
doubt, use the next heavier gage. The smaller the
gage number (AWG), the heavier the cord.
10
Ampere
Rating
More
Than
Not
More
Than
0 6 18 16 16 14
6 10 18 16 14 12
10 12 16 16 14 12
12 16 14 12
Extension Cord Recommendations
Volts
120 25 50 100 150
AWG
Total length of
cord in feet
Not
Recommended
Table 2
7.0 Operation
Always use approved safety
glasses or face shield. Failure to comply may
cause serious injury.
A bench grinder is designed for hand-grinding
operations such as sharpening chisels,
screwdrivers, drill bits, removing excess metal, and
smoothing and polishing metal surfaces.
A Medium Grain Abrasive Wheel is suitable for
rough grinding where a considerable amount of
metal must be removed or when obtaining a smooth
finish is not important. A Fine Grain Abrasive Wheel
should be used for sharpening tools or grinding to
close size tolerances because it removes metal
more gradually for precision grinding and gives work
a smooth finish.
Wire brushing provides a fast way to remove rust
scale, burrs, and point from metal. Use coarse wire
brushes for hard cleaning jobs. Use fine wire
brushes for polishing and finish work. When brush
tips become dull, reverse the brush on the grinder.
7.1 On/Off Switch
will help prevent a groove from forming at one
place on the wheel.
7. Keep a tray filled with water and dip your work
into it regularly to prevent overheating.
Overheating can weaken metals. Do not apply
water directly to a grinding wheel.
8. Do not use the side of the grinding wheel; this
puts dangerous stress on the wheel.
9. When wheel becomes loaded or dull, use an
approved grinding wheel dresser and dress the
wheel face.
8.0 Adjustments
8.1 Eye Shield Tilt Adjustment
1. Loosen lock knob (A1, Figure 8-1).
2. Adjust eye shield (A
3. Tighten lock knob (A
) to desired tilt angle.
2
).
1
When grinder is turned off, the
wheel may take a few moments to completely
stop.
Press rocker or toggle switch to start and stop
grinder.
Note: After extended operation, the grinder housing
may be warm to the touch. This is not abnormal.
7.2 Precautions
7.2.1 Wheel grinding
1. Before starting grinder, turn wheels by hand to
verify they are clear of obstructions and turn
freely. The tool rests and spark guards should
not touch the wheel.
2. Keep tool rest and spark guard to within 1/16"
of grinding wheel.
3. Turn on grinder and allow it to reach full running
speed before starting to grind.
4. Adjust the eye shields as needed.
5. Keep a steady, moderate pressure on the
workpiece and keep it moving at an even pace
for smooth grinding. Pressing too hard
overheats the motor and prematurely wears the
grinding wheel. Note the original bevel angle on
the item to be sharpened and try to maintain the
same shape. The grinding wheel should rotate
into the object being sharpened.
6. If grinding a narrow workpiece, slide it laterally
across width of wheel. Using full width of wheel
Figure 8-1: eye shield adjustment
8.2 Spark Guard
As the wheel wears down, the spark guard must be
re-adjusted to maintain a maximum 1/16" distance.
Refer to Figure 8-1.
1. Loosen two hex cap screws (B
2. Slide spark guard (B
grinding wheel surface.
3. Tighten screws (B
) to 1/16" distance from
2
).
1
).
1
11
8.3 Tool Rest
As the wheel wears down, the tool rest must be readjusted to maintain a maximum 1/16" distance.
Refer to Figure 8-1.
1. Loosen two hex cap screws (C
2. Slide tool rest (C
wheel.
3. Tighten screws (C
) to within 1/16" from grinding
2
).
1
).
1
Model
JBG-6W
JBG-8W
Your bench grinder will accept most polishing and
buffing wheels available at dealers and hardware
stores.
Wheel
Diameter
6" 3/4" 1/2"
8" 1" 5/8"
Maximum
Table 3
Width
Center
Hole
9.0 User-maintenance
For safety, turn switch to OFF and remove plug from
power source outlet before adjusting or performing
maintenance on the bench grinder.
If the power cord is worn, cut or damaged in any
way, have it replaced immediately.
9.1 Ring Test
Before replacing a grinding wheel, perform this
simple test on the replacement wheel:
1. Loop a piece of string through the grinding
wheel hole and suspend the wheel by holding
up the string.
2. Tap the wheel with a piece of scrap wood or
wooden dowel.
3. A good wheel will "ring"; a defective wheel will
"thud". Discard any wheel that does not "ring".
An internal defect may not be apparent by visual
inspection alone. The ring test may identify an
internal crack or void.
9.2 Care of Grinding Wheels
The use of any other accessory
is not recommended and may result in serious
injury!
To change a wheel (see Figure 9-1):
1. Disconnect grinder from power source.
2. Loosen spark guard (A) and tool rest (B) and
move them away from wheel.
3. Remove wheel guard using a screwdriver.
4. Stabilize wheel by holding opposite wheel
firmly, or placing a wood wedge between wheel
and tool rest.
5. Unscrew arbor nut (C) with wrench. NOTE: Left
wheel nut has left-hand threads; turn nut
clockwise to loosen. Right wire wheel nut has
right-hand threads; turn nut counterclockwise to
loosen.
6. Remove outer flange (D), wheel (E), and inner
flange.
7. Clean flanges. Check the flanges to make sure
they are flat. Wheel flanges that are not flat will
cause the wheel to wobble.
In normal use, grinding wheels may become
cracked, grooved, rounded at the edges, chipped,
out of true or loaded with foreign material.
A cracked wheel should be replaced
IMMEDIATELY. The other conditions can be
remedied with a dressing tool. New wheels
sometimes require dressing to make them round.
See sect. 9.5.
9.3 Changing Wheels
The JET bench grinder comes equipped with a
general purpose grinding wheel. Wheels vary
according to types of abrasive, hardness, grit size,
and structure. Contact your local distributor for the
proper grinding wheel or wire wheel for your
application.
If you replace a wheel, obtain one with a safe rated
speed at least as high as the NO LOAD RPM
marked on the grinder's nameplate. Refer to Table
3 to determine correct dimensions for the
replacement wheel.
12
Figure 9-1: wheel replacement
8. Inspect the new grinding wheel and perform a
“ring test” (sect. 9.1). Do not install a damaged
wheel.
9. Install inner flange, wheel (E), outer flange (D)
and nut (C) on the shaft. Tighten nut.
Do not overtighten nut; this
may cause wheel to crack. Maximum safe torque
on nut is 20 lbf•ft (270 kgf•cm).
10. Reinstall guard cover. Adjust spark guard and
tool rest to 1/16" clearance from wheel.
9.4 Wheel balancing
With the grinder unplugged from the power
source, and the arbor nut snugged down, rotate
wheel by hand and observe its motion.
A grinding wheel has proper balance when:
1. The wheel’s outside face spins true and round;
that is, its circumference rotates concentric to
the arbor.
2. There is no side-to-side wobble.
The operator who takes time to patiently perform
needed adjustments will be rewarded by a wheel
running true, and accurate grinding of work pieces.
9.4.1 Adjusting concentricity
If the outside face is not rotating concentric to arbor,
try shifting the wheel closer to arbor centerline
before tightening the nut.
Another method of achieving concentricity is the use
of a wheel dresser. “Dressing” is the removal of the
current layer of abrasive to expose a fresh surface.
A wheel dresser is also used to “true” a wheel; that
is, to make the grinding surface parallel to the tool
rest, so the entire wheel face presents an even
surface to the work piece. Proper use of a wheel
dresser will eliminate high spots and result in
concentric rotation about the arbor, as well as
minimize vibration. See sect. 9.5.
9.4.2 Correcting side-to-side wobble
The JBG-W Grinder has large, machined flanges,
making wobble unlikely if a good quality grinding
wheel is used. Should a wheel exhibit need for
adjustment:
1. Loosen nut and rotate outer flange a small
amount. Snug the nut and spin the wheel by
hand to check.
2. If wobble still exists, continue repeating step 1,
rotating outer flange incrementally in the same
direction. See Figure 9-2. Make sure to keep
the wheel in same position each time.
3. If complete rotation of outer flange has proved
ineffective, remove nut, outer flange, and wheel
(keep wheel in same orientation by placing a
pencil mark somewhere on it for reference).
Then rotate inner flange about 90° and repeat
the above steps for outer flange.
4. Continue this combination of flange movements
until the wobble is eliminated.
If required, a shim made of paper or card stock may
be placed between flange and wheel.
Figure 9-2: wheel balancing
NOTE: Very slight wobble may still exist at spin-up
and spin-down, but will not affect normal speed
operation.
9.5 Dressing the wheels
Below is a general procedure for dressing a grinding
wheel. Always consult the wheel dresser
manufacturer’s instructions for specific information
pertaining to the tool.
Use safety glasses or face
shield during dressing operations.
1. Back off the tool rest enough to allow the
dresser to hook over its inside edge (see Figure
9-3). Tighten tool rest in position.
2. Turn on grinder and allow it to reach operating
speed.
3. Set wheel dresser on tool rest and bring it into
contact with wheel by raising its handle. Hold
the dresser firmly.
Note: If sparks appear, increase the pressure
of the dresser discs against the wheel.
4. Move dresser evenly left and right across wheel
face until wheel looks clean and is square to tool
rest.
5. Remove dresser, and adjust tool rest to 1/16”
away from the newly dressed wheel.
13
Figure 9-3: wheel dressing
9.6 Cleaning
Metal shavings may still be hot
from recent grinding operations. Make sure
shavings and debris are cold before cleaning
the grinder.
Avoid use of the following
cleaning chemicals or solvents: gasoline,
carbon tetrachloride, chlorinated solvents,
ammonia and household detergents containing
ammonia.
Brush all shavings from motor housing, tool rest,
and wheel guard. Check grinding wheel for cracks
and chips. Replace if damaged.
9.7 Lubrication
All motor bearings are permanently lubricated and
sealed at the factory and require no additional
lubrication.
9.8 Additional servicing
Any other servicing should be performed by an
authorized service representative.
14
10.0 Troubleshooting JBG-6W, JBG-8W Bench Grinders
Table 4
Symptom Possible Cause Correction *
Motor will not start. Not connected to power source. Verify that switch is on and plug is properly
inserted into receptacle.
Motor cord cut or abraded. Replace with new cord.
Motor will not start;
fuses blow or circuit
breakers trip.
Motor fails to develop
full power.
Wheels cannot rotate because of
obstruction.
Plug on cord is faulty. Replace with new plug.
Low line voltage. Check power line for proper voltage.
Fuse blown or circuit breaker tripped. Re-set. May be too many machines on one
Faulty switch. Replace switch.
Faulty capacitor. Replace capacitor.
Open circuit in motor or loose
connection.
Motor fault. Contact JET technical service.
Too many machines running on same
circuit.
Incorrect fuse. Try time delay fuse, or go to circuit with
Wheels cannot rotate because of
obstruction.
Undersized extension cord. Use correct size extension cord.
Short circuit in line cord or plug. Inspect cord or plug for damaged insulation
Short circuit in motor or loose
connections.
Low line voltage. Check power line for proper voltage.
Capacitor or motor failure. Contact JET technical service.
Unplug and turn grinding wheel by hand to
ensure free movement. Restart.
line; use dedicated line if needed.
Inspect all lead connections on motor for
loose or open connections.
Turn off other machines and try again. Use
dedicated circuit if needed.
higher rated fuse or circuit breaker.
Unplug and turn grinding wheel by hand to
ensure free movement. Clear any
obstructions and restart.
and shorted wires.
Inspect all connections on motor for loose
or shorted terminals or worn insulation.
Motor overheats. Motor overloaded. Reduce pressure against wheel. Make sure
grit size is appropriate for the job.
Poor motor ventilation. Unplug and clean out around motor;
provide better air circulation.
Capacitor or motor failure. Contact JET technical service.
Motor stalls, resulting
in blown fuses or
tripped circuit.
Motor slows. Motor overloaded. Reduce load on motor; do not press so
Motor overloaded. Reduce load on motor; do not press so
hard when grinding.
Capacitor or motor failure. Contact JET technical service.
Short circuit in motor or loose
connections.
Low voltage. Correct low voltage conditions.
Incorrect fuses or circuit breakers in
power line.
Low line voltage. Check power line for proper voltage.
Loose connections. Inspect and remedy.
15
Inspect connections on motor for loose or
shorted terminals or worn insulation.
Install correct fuses or circuit breakers.
hard when grinding.
Symptom Possible Cause Correction *
Frequent fuse or circuit
breaker failure.
Motor overload. Reduce load on motor; do not press so
hard when grinding.
Electrical circuit overload; too many
machines running on same circuit.
Incorrect fuse or circuit breaker. Have electrician upgrade service to outlet.
Turn off other machines and try again. Use
dedicated circuit if needed.
Excessive vibration. Wheel(s) out of balance; wobbling or
not rotating concentric to arbor.
Improper mounting. Secure grinder firmly to bench or stand.
* WARNING: Some corrections may required a qualified electrician.
Dress wheel or replace it. Adjust wheel
imbalance according to instructions in this
manual.
16
11.0 Optional accessories
These accessory items, purchased separately, are available for your JET bench grinder. Contact your dealer to
order, or call JET at the phone number on the cover.
IBG8-54
Wheel Dresser, Ø 1-1/4”
578172
Stand for Grinders
Deluxe Stand for Grinders
578173
The following accessories are for using the Grinder with the JET #414800 (JDCS-505) Dust Collection Stand:
414820 Reducer, 3 in. to 2 in.
414812 0.6M Hose, Heat Resistant, ø2 x 24.4 in.
12.0 Replacement Parts
Replacement parts are listed on the following pages. To order parts for the main grinder unit or reach the JET
service department, call 1-800-274-6848 Monday through Friday, 8:00 a.m. to 5:00 p.m. CST. Having the Model
Number and Serial Number of your machine available when you call will allow us to serve you quickly and
accurately.
Non-proprietary parts, such as fasteners, can be found at local hardware stores, or may be ordered from JET.
Some parts are shown for reference only, and may not be available individually.
17
12.1.1 JBG-W series Grinder with Wire Wheel – Exploded View
18
12.1.2 JBG-6W, JBG-8W Grinders – Parts List
Index No Part No Description Size Qty
1 ................ JBG6A-02P ............... Shaft and Rotor Assembly ....................................... ...................................... 1
.................. JBG8A-02P ............... Shaft and Rotor Assembly ....................................... ...................................... 1
3 ................ JBG6A-03 .................. Stator Assembly....................................................... ...................................... 1
.................. JBG8A-03 .................. Stator Assembly....................................................... ...................................... 1
5 ................ JBG6A-05G ............... Motor Housing ......................................................... ...................................... 1
.................. JBG8A-05G ............... Motor Housing ......................................................... ...................................... 1
6 ................ JBG6A-06G ............... Base ........................................................................ ...................................... 1
.................. JBG8A-06G ............... Base ........................................................................ ...................................... 1
7 ................ JBG6A-07 .................. Cross Screw ........................................................... 1/4 x 7/8 ........................ 4
8 ................ TS-0720071 .............. Lock Washer ............................................................ 1/4 ................................. 4
9 ................ TS-0561011 .............. Hex Nut .................................................................... 1/4 ................................. 4
10 .............. JBG6A-10 .................. Fan .......................................................................... ...................................... 1
.................. JBG8A-10 .................. Fan .......................................................................... ...................................... 1
11 .............. BB-6202ZZ ................ Ball Bearing (JBG-6A) ............................................. ...................................... 2
.................. BB-6204ZZ ................ Ball Bearing (JBG-8A) ............................................. ...................................... 2
12 .............. JBG6A-12G ............... Cover ....................................................................... ...................................... 2
.................. JBG8A-12G ............... Cover ....................................................................... ...................................... 2
15 .............. JBG6A-15 .................. Screw ....................................................................... 3/16 x 5/8. ..................... 4
16 .............. JBG6A-16B ............... Inner Wheel Guard – left ......................................... ...................................... 1
.................. JBG8A-16B ............... Inner Wheel Guard – left ......................................... ...................................... 1
17 .............. JBG6A-17B ............... Inner Wheel Guard – right ....................................... ...................................... 1
.................. JBG8A-17B ............... Inner Wheel Guard – right ....................................... ...................................... 1
19 .............. JBG6A-19 .................. Cross Screw ............................................................ 1/4 x 1/2 ........................ 4
20 .............. JBG6A-20 .................. Wheel Flange .......................................................... 1/2 I.D ........................... 4
.................. JBG8A-20 .................. Wheel Flange .......................................................... 5/8 I.D ........................... 4
21 .............. 576207 ...................... Grinding Wheel ........................................................ 6 x 3/4, 36 grit ............... 1
.................. 576223 ...................... Grinding Wheel ........................................................ 8 x 1, 36 grit .................. 1
21A ............ JBG6W-21A .............. Wire Wheel .............................................................. 6 x 1/2 ........................... 1
.................. JBG8W-21A .............. Wire Wheel .............................................................. 8 x 1/2 ........................... 1
22 .............. JBG6A-22 .................. Nut - left hand thread ............................................... 1/2 ................................. 1
.................. JBG8A-22
23 .............. JBG6A-23 .................. Nut - right hand thread ............................................. 1/2 ................................. 1
.................. JBG8A-23 .................. Nut - right hand thread ............................................. 5/8 ................................. 1
24 .............. JBG6A-24B ............... Outer Wheel Guard – left ......................................... ...................................... 1
.................. JBG8A-24P ............... Outer Wheel Guard – left ......................................... ...................................... 1
25 .............. JBG6A-25B ............... Outer Wheel Guard – right ...................................... ...................................... 1
.................. JBG8A-25P ............... Outer Wheel Guard – right ...................................... ...................................... 1
26 .............. JBG6A-26 .................. Cross Screw ............................................................ 1/4 x 1/2 ........................ 8
27 .............. JBG6A-27 .................. Tool Rest – left ........................................................ ...................................... 1
.................. JBG8A-27 .................. Tool Rest – left ........................................................ ...................................... 1
28 .............. JBG6A-28 .................. Tool Rest – right ...................................................... ...................................... 1
.................. JBG8A-28 .................. Tool Rest – right ...................................................... ...................................... 1
29 .............. TS-0680031 .............. Flat Washer ............................................................. 5/16 ............................... 4
30 .............. TS-0051031 .............. Hex Cap Bolt ........................................................... 5/16 x 3/4 ...................... 4
31 .............. JBG6A-31 .................. Rubber Guide .......................................................... ...................................... 1
.................. JBG8A-31 .................. Rubber Guide .......................................................... ...................................... 1
32 .............. JBG6A-32 .................. Cord Plate ................................................................ ...................................... 1
.................. JBG8A-32 .................. Cord Plate ................................................................ ...................................... 1
34 .............. JBG6A-34 .................. Cross Screw ............................................................ 3/16 x 1/4 ...................... 2
35 .............. JBG6A-35 .................. Capacitor (125 VAC, 100MFD) ................................ ...................................... 1
.................. JBG8A-35 .................. Capacitor (125 VAC, 200MFD) ................................ ...................................... 1
36 .............. JBG6A-36 .................. Bracket .................................................................... ...................................... 1
.................. JBG8A-36 .................. Bracket .................................................................... ...................................... 1
38 .............. JBG6A-38 .................. Screw ....................................................................... 3/16 x 1/4 ...................... 1
39 .............. JBG6A-39 .................. Power Cord .............................................................. ...................................... 1
.................. JBG8A-39 .................. Power Cord .............................................................. ...................................... 1
40 .............. JBG6A-40 .................. Cross Screw ............................................................ 3/16 x 3/8 ...................... 1
41 .............. JBG6A-41 .................. Star Washer ................................
42 .............. JBG6A-42 .................. Clip .......................................................................... ...................................... 1
.................. JBG8A-42 .................. Clip .......................................................................... ...................................... 1
.................. Nut - left hand thread ............................................... 5/8 ................................. 1
............................. 3/16 ............................... 1
19
Index No Part No Description Size Qty
44 .............. JBG6A-44 .................. Rocker Switch .......................................................... ...................................... 1
.................. JBG8A-44 .................. Toggle Switch .......................................................... ...................................... 1
45 .............. JBG6A-45 .................. Switch Plate ............................................................. ...................................... 1
.................. JBG8A-45 .................. Switch Plate ............................................................. ...................................... 1
46 .............. JBG6A-46 .................. Screw ....................................................................... 3/16 x 1/4 ...................... 2
47 .............. JBG6A-47 .................. Base Plate ............................................................... ...................................... 1
.................. JBG8A-47 .................. Base Plate ............................................................... ...................................... 1
49 .............. JBG6A-49 .................. Cross Screw ............................................................ 3/16 x 1/2 ...................... 4
.................. JBG8A-49 .................. Cross Screw ............................................................ 3/16 x 1/2 ...................... 4
50 .............. JBG8A-50 .................. Spark Guard – left ................................................... ...................................... 1
51 .............. JBG8A-51 .................. Spark Guard – right ................................................. ...................................... 1
52 .............. TS-0720071 .............. Lock Washer ............................................................ 1/4 ................................. 2
53 .............. TS-0680021 .............. Flat Washer ............................................................. 1/4 ................................. 6
54 .............. JBG6A-54 .................. Cross Screw ............................................................ 1/4 x 1/2 ........................ 2
54A ............ JBG6A-54 .................. Cross Screw ............................................................ 1/4 x 3/8 ........................ 4
55 .............. JBG8A-55 .................. Eye Shield Bracket – left ......................................... ...................................... 1
56 .............. JBG8A-56 .................. Eye Shield Bracket – right. ...................................... ...................................... 1
57 .............. JBG6A-57 .................. Lock Knob ................................................................ 1/4 ................................. 2
58 .............. JBG6A-58 .................. Cross Screw ............................................................ 3/16 x 3/8 ...................... 4
59 ............. JBG8A-59 .................. Eye Shield .............................................................. ...................................... 2
.................. JBG8A-59A ............... Eye Shield Assembly (includes #50 thru 60, LH and RH sets) ....................... 1
60 .............. JBG8A-60 .................. Eye Shield Plate ...................................................... ...................................... 2
61 .............. LM000335 ................. Identification Label, JBG-6W ................................... ...................................... 1
.................. LM000336 ................. Identification Label, JBG-8W ................................... ...................................... 1
63 .............. JBG6A-63 .................. Direction Label ......................................................... ...................................... 2
64 .............. JBG6A-64 .................. Rubber Foot ............................................................. ...................................... 4
65 .............. JBG6A-65 .................. Switch Seat ................................
.................. JBG8A-65 .................. Switch Seat .............................................................. ...................................... 1
66 .............. JBG6A-66 .................. Centrifugal Start Switch ........................................... ...................................... 1
.................. JBG8A-66 .................. Centrifugal Start Switch ........................................... ...................................... 1
67 .............. JBG6W-67 ................. Bushing .................................................................... ...................................... 1
.................. JBG8W-67 ................. Bushing .................................................................... ...................................... 1
.............................. ...................................... 1
20
13.0 Wiring Diagram for JBG-6W, JBG-8W Grinders
21
14.0 Warranty and service
JET® warrants every product it sells against manufacturers’ defects. If one of our tools needs service or repair, please
contact Technical Service by calling 1-800-274-6846, 8AM to 5PM CST, Monday through Friday.
Warranty Period
The general warranty lasts for the time period specified in the literature included with your product or on the official
JET branded website.
JET products carry a limited warranty which varies in duration based upon the product. (See chart below)
Accessories carry a limited warranty of one year from the date of receipt.
Consumable items are defined as expendable parts or accessories expected to become inoperable within a
reasonable amount of use and are covered by a 90 day limited warranty against manufacturer’s defects.
Who is Covered
This warranty covers only the initial purchaser of the product from the date of delivery.
What is Covered
This warranty covers any defects in workmanship or materials subject to the limitations stated below. This warranty
does not cover failures due directly or indirectly to misuse, abuse, negligence or accidents, normal wear-and-tear,
improper repair, alterations or lack of maintenance. JET woodworking machinery is designed to be used with Wood.
Use of these machines in the processing of metal, plastics, or other materials outside recommended guidelines may
void the warranty. The exceptions are acrylics and other natural items that are made specifically for wood turning.
Warranty Limitations
Woodworking products with a Five Year Warranty that are used for commercial or industrial purposes default to a
Two Year Warranty. Please contact Technical Service at 1-800-274-6846 for further clarification.
How to Get Technical Support
Please contact Technical Service by calling 1-800-274-6846. Please note that you will be asked to provide proof
of initial purchase when calling. If a product requires further inspection, the Technical Service representative will
explain and assist with any additional action needed. JET has Authorized Service Centers located throughout the
United States. For the name of an Authorized Service Center in your area call 1-800-274-6846 or use the Service
Center Locator on the JET website.
More Information
JET is constantly adding new products. For complete, up-to-date product information, check with your local distributor
or visit the JET website.
How State Law Applies
This warranty gives you specific legal rights, subject to applicable state law.
Limitations on This Warranty
JET LIMITS ALL IMPLIED WARRANTIES TO THE PERIOD OF THE LIMITED WARRANTY FOR EACH PRODUCT.
EXCEPT AS STATED HEREIN, ANY IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
PARTICULAR PURPOSE ARE EXCLUDED. SOME STATES DO NOT ALLOW LIMITATIONS ON HOW LONG AN
IMPLIED WARRANTY LASTS, SO THE ABOVE LIMITATION MAY NOT APPLY TO YOU.
JET SHALL IN NO EVENT BE LIABLE FOR DEATH, INJURIES TO PERSONS OR PROPERTY, OR FOR
INCIDENTAL, CONTINGENT, SPECIAL, OR CONSEQUENTIAL DAMAGES ARISING FROM THE USE OF OUR
PRODUCTS. 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.
JET sells through distributors only. The specifications listed in JET printed materials and on official JET website are
given as general information and are not binding. JET reserves the right to effect at any time, without prior notice,
those alterations to parts, fittings, and accessory equipment which they may deem necessary for any reason
whatsoever. JET
Product Listing with Warranty Period
90 Days – Parts; Consumable items
1 Year – Motors; Machine Accessories
2 Year – Metalworking Machinery; Electric Hoists, Electric Hoist Accessories; Woodworking Machinery used
for industrial or commercial purposes
5 Year – Woodworking Machinery
Limited Lifetime – JET Parallel clamps; VOLT Series Electric Hoists; Manual Hoists; Manual Hoist
Accessories; Shop Tools; Warehouse & Dock products; Hand Tools; Air Tools
NOTE: JET is a division of JPW Industries, Inc. References in this document to JET also apply to JPW Industries,
Inc., or any of its successors in interest to the JET brand.
®
branded products are not sold in Canada by JPW Industries, Inc.
22
23
427 New Sanford Road
LaVergne, Tennessee 37086
Phone: 800-274-6848
www.jettools.com
24
Loading...