Ryobi P421 - Manual (Page 10)

10 — English
To replace the guard:
 Remove the battery pack from the grinder.

 Depress spindle lock and rotate clamp nut until spindle
locks.
 Loosen and remove clamp nut from spindle using the
wrench provided.
 Remove grinding wheel and disc flange.

 Unlock the guard clasp by pulling the clasp out, away
from the grinder.
  Open clasp fully and twist guard to release it from the
locking groove in the tool housing.
  Remove guard.
 Place the new guard on the shoulder of the bearing cap.
 Rotate guard to the correct position. Refer to
Positioning
the Guard earlier in this manual.
NOTE: Be sure the raised ridge on the guard is seated in
the groove on the bearing cap.
 Reassemble disc flange, grinding wheel, and clamp nut.
Refer to Installing Grinding Wheel earlier in this manual.
 Tighten the clamp nut securely with the wrench provided.
BATTERY PACK REMOVAL AND
PREPARATION FOR RECYCLING
WARNING:
Upon removal, cover the battery pack’s terminals with
heavy-duty adhesive tape. Do not attempt to destroy or
disassemble battery pack or remove any of its compo-
nents. Batteries must be recycled or disposed of properly.
Also, never touch both terminals with metal objects and/
or body parts as short circuit may result. Keep away from
children. Failure to comply with these warnings could
result in fire and/or serious injury.
MAINTENANCE
WARNING:
When servicing, use only identical replacement parts.
Use of any other part could create a hazard or cause
product damage.
WARNING:
Always wear eye protection with side shields marked to
comply with ANSI Z87.1, along with hearing protection.
Failure to do so could result in objects being thrown into
your eyes and other possible serious injuries.
WARNING:
To avoid serious personal injury, always remove the
battery pack from the tool when cleaning, performing any
maintenance, or when storing the tool.
GENERAL MAINTENANCE
Avoid using solvents when cleaning plastic parts. Most
plastics are susceptible to damage from various types of
commercial solvents and can be damaged by their use. Use
clean cloths to remove dirt, dust, oil, grease, etc.
WARNING:
Do not at any time let brake fluids, gasoline, petroleum-
based products, penetrating oils, etc., come in contact
with plastic parts. Chemicals can damage, weaken or
destroy plastic which could result in serious personal
injury.
REPLACING THE GUARD
See Figure 2, page 12.
WARNING:
Do not change or loosen guard screw. Failure to heed this
warning may cause the guard to become loose during
operation resulting in serious personal injury.
After extended use, the guard may wear and need replacing.
If you drop the grinder and damage the guard it may also be
necessary for you to replace it.
NOTE: Figures (illustrations) start on page 12
after French and Spanish language sections.
This product has a Three-year
Limited Warranty.
For Warranty details go to
www.ryobitools.com
NOTICE:
If the grinder is held in one spot too long, it will gouge
and cut grooves in the workpiece. If the grinder is held
at too sharp an angle, it will also gouge the workpiece
because of concentration of pressure on a small area.
 Use just enough pressure to keep the grinder from
chattering or bouncing.
NOTE: Heavy pressure will decrease the grinder’s speed and
put a strain on the motor. Normally the weight of the tool
alone is adequate for most grinding jobs. Use light pressure
when grinding jagged edges or loose bolts where there is the
potential for the grinder to snag on the metal edge.

Lift the grinder away from the workpiece before turning
off the grinder.
OPERATION