Echo 74624S Owners Manual v.1 - Manual (Page 25)

Page 19 6” Chipper Pro Operator’s Manual
5.2 REMOVING AND SHARPENING
THE CHIPPER BLADES
To remove the chipping blades for sharpening:
1. Remove the two 3/8 inch retaining bolts holding access
cover to main frame assembly.
2. Tilt access cover over to allow rotor access. The chipper
will not operate with an open cover. Rotate the rotor to
access the bolts holding the blades. To remove the blades,
open the access cover from the top of the feed roller.
3. Remove the two allen head bolts holding the blade itself.
Repeat for all four blades. The four chipping blades have
two edges per blade and can be reversed one time each
before sharpening. Tighten bolts to proper torque and se-
cure access cover.
Sharpening the chipper blades:
Depending on the type of wood fed into the chipper, the
blades will eventually dull, making it difficult to feed material
and produce chips. Check the blades for sharpness every 8
hours.
Regrind the angled edge of the chipping blades to 45 degrees.
(refer to figure below) Grind the blades on a bench grinder or
by a professional. Use some type of fixture to correctly hold
the blade at the proper angle. Be careful when grinding so
that the blade does not become overheated and change
color (This will remove the heat-treated properties). Use short
grinding times and cool with water or some type of liquid
coolant. Try to remove an equal amount off of each blade to
maintain rotor balance. The blades can receive up to
approximately 6 sharpenings depending on the amount of
material removed to restore a razor-sharp edge.
Never sharpen or back grind the flat side of the chipping
blade. This will cause the edge to roll and damage the chipper
blade, resulting in poor chipping performance.Small
imperfections such as nicks, burrs, etc. on the blade may
affect the chipping performance of the machine. Sharpen
the blade to remove imperfections. Replace the blade if
imperfections are too large.
Replace the blade after the allotted sharpening amount dips
below the chipper outlet (See Fig. 25 “A”). If you do not
replace the blade, damage to the machine will occur due to
pieces of wood jamming into the chipping disk and blade.
When completed, replace the chipping blades and tighten
the bolts to 75 ft. lbs. Install all safety screens and guards
and resume chipping.
Fig. # 24 Exposing the chipper blades
To prevent personal injury or property damage: Shut
off engine, remove ignition key and make sure that all
moving parts have come to a complete stop before ser-
vicing, adjusting or repairing.
WARNING
The chipping blades are sharp!! Use care when working
on the machine to avoid injury.
WARNING
Fig. # 25 Sharpening the chipper blades
.38
45°
A
MOUNTING SURFACE
DO NOT GRIND
SHARPENED
SURFACE SHARPENED
SURFACE
CHIPPING
DISC
CHIPPER
OUTLET
ALLOTTED
SHARPENING AMOUNT
.13
Figure # 26 Imperfections that require replacement
Service & Maintenance