Technical data

13773-001

51-20

Page 36 30 Nov 2000

(3) Core Replacement

If the damage penetrated the inner laminate or there is major damage to the core, a core section

will have to be replaced and the integrity of the inner laminate restored. (See Figure 51-207)

(a) Using a utility knife, carefully cut through the core to the inner laminate.

(b) Cut perpendicular to the outer surface at the inside edge of the damage, do not score the

inner laminate. Remove enough core to expose a border of undamaged inner laminate

approximately 0.5 inch wide for each ply of the repair. A 3-ply damaged laminate would be

trimmed back 1.5 inches.

aration between core and inner laminate during this operation.

(d) Inspect for separation of the inner laminate from the core. Continue to sand back until all

separated laminate is removed.

Note: If the inner laminate is damaged, a backing plate will need to be made and

bonded into place and the inner laminate repaired prior to replacing core.

(e) Cut a piece of inner core to fit snugly into damaged area.

Note: Replacement core can be slightly thicker than required. Replacement core

will be sanded down after bonding in place.

(f) Before bonding in core, sand the inner laminate thoroughly with 80-grit to 120-grit paper.

(g) Remove all dust and debris with clean oil free compressed air and a vacuum.

Note: Moisten cloth with cleaning solvent. Never pour solvent directly onto lami-

nate, allowing laminate to soak up cleaning solvent.

(h) Solvent clean bonding surfaces of outer laminate with isopropyl alcohol. (Refer to 20-30)

(i) Mix filler paste. (Refer to 51-20)

(j) Apply paste to edges and back side of core and a thin layer to the inner laminate surface.

(k) Insert core into damaged area and lightly clamp core into place.

Note: On contoured surfaces it will be necessary to apply enough pressure to

maintain contact between core and inner laminate. Small weights may be

used to apply enough pressure to maintain contact between core and inner

laminate.

(l) Allow resin to fully cure. (Refer to 51-20)

(m) Continue repair by following the Outer Laminate Repair procedures. (Refer to 51-20)