Hartzell HC-B3-2 Series Owner's Manual And Logbook page 238

(2) Calculate the area of repair using Figure 6-5 and the
following formulas:
(a) For leading and trailing edge damage:
Depth of the damage x 10. Refer to Example 2.
NOTE:
(b) For face and camber side damage:
Depth of damage x 20. Refer to Example 3.
(3) Repair damage to the leading or trailing edge of the
blade by removing material from the bottom of the
damaged area.
(a) Remove material from this point out to both sides of
the damage to form a smooth, blended depression
that maintains the original shape of the blade airfoil.
(4) Repair damage to the blade face or camber side by
removing material from the bottom of the damaged area.
(a) Remove material from this point out to both sides of
the damage to form a smooth, blended depression
that maintains the original shape of the blade airfoil.
(b) Repairs that form a continuous line across the blade
section (chordwise) are not permitted.
(5) After filing or sanding of the damaged area, use emery
cloth to polish the area, then remove any file marks
using crocus cloth.
(6) Inspect the repaired area with a 10X magnifying glass.
(a) Be sure that no indication of the damage, file marks,
or coarse surface finish remain.
(7) If inspections show any remaining blade damage, repeat
steps (5) and (6) of this procedure until no damage
remains.
(8) After repair, Hartzell Propeller Inc. recommends
penetrant inspection of the blade in accordance with
Hartzell Propeller Inc. Standard Practices Manual 202A,
(61-01-02).
MAINTENANCE PRACTICES
Propeller Owner's Manual
The leading edge includes the first 10% of
chord from the leading edge. The trailing
edge consists of the last 20% of chord
adjacent to the trailing edge.
61-00-39
139
Rev. 17 Apr/20
Page 6-18