4
WARNING: ALWAYS wear proper personal hearing protection that conforms to 
ANSI S12.6 (S3.19) during use. Under some conditions and duration of use, noise 
from this product may contribute to hearing loss.
WARNING Use extra care when working into a corner because a sudden, sharp 
movement of the grinder may be experienced when the wheel or other accessory 
contacts a secondary surface or a surface edge. 
 • The label on your tool may include the following symbols. The symbols and their 
definitions are as follows:
V ................. volts A ...............amperes
Hz ............... her tz W ..............watts
min ............. minutes ...........alternating current
.......... direct current ...........alternating or direct current
 ..............Class I Construction no..............no load speed
 ................... (grounded) .............earthing terminal
 ...............Class II Construction .............safety alert symbol
 ................... (double insulated) RPM ..........revolutions per minute
…/min ........ per minute BPM ..........beats per minute
IPM.............impacts per minute
COMPONENTS (FIG. 1)
 A. Paddle Switch H. Threaded Clamp Nut
 (D28402-XE, D28402N-XE) I. Guard
 B. Lock-Off Lever J. Lock On Button 
 C. Spindle Lock Button K. Dust Ejection System (DES)
 D. Spindle (not shown) (Not equipped on D28139)
 E. Side Handle L. Slider Switch
 F. Grinding Wheel
 G. Anti-Lockup Backing Flange
NOTE: Type 1 Guard and Accessories available as option accessories.
complete stop. Never attempt to remove the unit from the work or pull the unit 
backward while the wheel is in motion or kickback may occur. Investigate and 
take corrective actions to eliminate the cause of wheel binding.
 • When restarting a cut-off tool in the workpiece, check that the wheel is not 
engaged into the material. If wheel is binding, it may walk up or kickback from 
the workpiece as the tool is restarted.
 • Support large panels to minimize the risk of wheel pinching and kickback. 
Large panels tend to sag under their own weight. Support must be placed under 
the panel on both sides, near the line of cut and near the edge of the panel.
WARNING: ALWAYS use safety glasses. Everyday eyeglasses are NOT safety 
glasses. Also use face or dust mask if cutting operation is dusty. ALWAYS WEAR 
CERTIFIED SAFETY EQUIPMENT:
• ANSI Z87.1 eye protection (CAN/CSA Z94.3),
• ANSI S12.6 (S3.19) hearing protection,
• NIOSH/OSHA/MSHA respiratory protection.
WARNING: Some dust created by power sanding, sawing, grinding, drilling, and 
other construction activities contains chemicals known to cause cancer, birth defects 
or other reproductive harm. Some examples of these chemicals are:
• lead from lead-based paints,
• crystalline silica from bricks and cement and other masonry products, and 
• arsenic and chromium from chemically-treated lumber (CCA).
Your risk from these exposures varies, depending on how often you do this type of 
work. To reduce your exposure to these chemicals: work in a well ventilated area, and 
work with approved safety equipment, such as those dust masks that are specially 
designed to filter out microscopic particles.
 •Avoid prolonged contact with dust from power sanding, sawing, grinding, 
drilling, and other construction activities. Wear protective clothing and wash 
exposed areas with soap and water. Allowing dust to get into your mouth, eyes, 
or lay on the skin may promote absorption of harmful chemicals. 
WARNING: Use of this tool can generate and/or disburse dust, which may cause 
serious and permanent respiratory or other injury. Always use NIOSH/OSHA approved 
respiratory protection appropriate for the dust exposure. Direct particles away from 
face and body.