Technical data

13773-001
51-30
Page 4 30 Nov 2000
C. Fillers
Body filler and spot putty are two types of fillers used for repairing cosmetic blemishes and minor sur-
face defects. Body filler is primarily used for repairing small dents and to fill large surface imperfections
and gaps at seams or bond joints. Spot putty is used to fill minute cosmetic defects such as pits and
minor scratches.
WARNING:
Aircraft control surface balance is critical to safe flight. If any paint, body filler,
striping, or other material is added to a control surface, the control must be re-
balanced. Mask flight control hinge bushings and bearings prior to applying sur-
facer or paint.
Note: Over large areas, body filler thickness shall not exceed 0.13 inch (3.3 mm). No more
than 15% of the surface may be covered with body filler and no more than 5% of the sur-
face area shall have filler thicker than 0.10 inch (2.5 mm). Body filler thickness in small
local areas (less the 10 square inches) or at seams and joints may exceed maximum
filler thickness. Filler thickness can be verified by inserting the pointed end of a toothpick
into uncured filler. (Refer to 51-30, Filler Thickness)
Body filler can be applied to primed or un-primed composite surfaces that are contami-
nate free. Areas that will receive body filler should be scuffed with 80-grit to 120-grit
sand paper or similar abrasive to improve adhesion.
It is preferable to use a finishing system (primer, surfacer, sealer, and paint) from one
manufacturer for the entire refinishing procedure.
(1) Application of Body Filler
(a) Acquire necessary tools, equipment, and supplies.
(b) Mask off all surfaces that do not require filling or where filler is not permitted.
CAUTION: Exercise caution when sanding composite surfaces to prevent sanding
through the existing surfacer coats or into the laminate. Never apply body
filler over a known or suspected area of damage. Cover any system that
may be contaminated by dust or where extraneous filler may cause the sys-
tem not to operate properly (for example, the flight control system and the
pitot/static system).
Description P/N or Spec. Supplier Purpose
Sandpaper 36-grit to 320-
grit
Any Source Abrade bonding
surfaces
Compressed air (contami-
nate free)
- Any Source General repair
Spot-Lite, Light Weight
BodyFiller
100445 Fibre Glass - Evercoat
Co.
Repair blemishes
Cleaner DX 330 PPG Industries, Inc. Surface prepara-
tion
Cotton cloth (clean and lint
free)
- Any Source General cleaning