Preliminary Requirements

Procedure

1. SUBTASK 72-32-87-323-051 Drill Holes on the Crack

   1. Refer to Figure.

   2. Measure the length of the crack ( = L in.).

   3. Multiply L by 2, then decrease this number to the nearest whole integer ( = N ).

   4. Drill holes at both ends of the crack.

      1. Use a 0.125 in. (3.17 mm) drill and hand drilling equipment.

   5. Drill quantity N of equally-spaced holes on the crack.

      1. Use a 0.125in. (3.17 mm) drill and hand drilling equipment.

         NOTE

         Existing damage hole can be used as a hole which is drilled in step D.

2. SUBTASK 72-32-87-110-053 Clean the Damaged Area on the Fan Case Liner Panel

   1. Refer to Figure.

   2. Hand clean the damaged area.

      1. Use CoMat 05-016 GARNET PAPER, 80-GRIT or CoMat 05-017 GARNET PAPER, 60 GRIT.

   3. Clean the repair area with a lint free cloth made moist with cleaning solvent.

      1. Use CoMat 01-348 CLEANING SOLVENT.

   4. Clean the repaired area with lint free cloth made with distilled water.

      1. Use CoMat 01-201 DISTILLED, DEIONIZED, DEMINERALIZED, OR REVERSE OSMOSIS (RO) WATER.

3. SUBTASK 72-32-87-350-051 Prepare the Bond Patches

   1. Refer to Figure.

   2. Find the three sizes of the bond patches for each crack.

   3. NOTE

      The size of the three bond patches for each crack are different.

      NOTE

      All three patches are installed on each repair area.

      Cut the bond patches to the correct sizes from the fiberglass cloth.

      1. Use CoMat 08-049 FIBREGLASS CLOTH.

4. SUBTASK 72-32-87-350-052 Prepare the Resin Mixture

   
   WARNING
   DO NOT GET RESIN MIXTURE ON YOUR SKIN OR IN YOUR EYES. PUT ON PROTECTIVE CLOTHING, GLOVES, GOGGLES AND A FACE MASK. USE THE RESIN IN A WELL VENTILATED AREA; DO NOT BREATHE THE GAS. IF YOU GET THE RESIN ON YOUR SKIN OR IN YOUR EYES GET MEDICAL AID IMMEDIATELY.

   1. Measure 100 parts of the CoMat 08-048 RESIN by weight.

      1. Use mass weighing scale.

   2. Measure 10 to 12 parts of the CoMat 08-047 HARDENER by weight.

      1. Use mass weighing scale.

   3. NOTE

      When mixed the life of the resin mixture is approximately one hour at room temperature.

      NOTE

      It is recommended that the quantity of mixture that you make each time is approximately 3.5 oz (100 gm).

      Put 3.5 oz (100 gm) of CoMat 08-048 RESIN into a container.

   4. Add between 0.35 and 0.42 oz (10 and 12 gm) of CoMat 08-047 HARDENER and mix them with a spatula.

5. SUBTASK 72-32-87-350-053 Apply the Resin Mixture onto the Repair Area and the Three Bond Patches

   1. Refer to Figure.

   2. Apply the resin mixture to the damage holes, the cracks, the stop holes and the surface to which the bond patches will be installed.

      1. Use CoMat 02-018 BRUSH, PAINT.

   3. Apply the resin mixture to both surface of the bond patches.

      1. Use CoMat 02-018 BRUSH, PAINT.

   4. Remove all unwanted resin mixture and make the surfaces smooth.

6. SUBTASK 72-32-87-350-054 Install the Bond Patches on the Repair Area of the Fan Case Liner Panel

   1. Refer to Figure.

   2. Install the first bond patch (smallest size) on the repair area to cover all the damaged area.

   3. Install the second bond patch (middle size) on the repair area to cover the first bond patch.

   4. Install the third bond patch (largest size) on the repair area to cover the second bond patch.

   5. Cure the bond patches for three hours at 131 to 149 deg F (55 to 65 deg C).

      1. Use an oven.

7. SUBTASK 72-32-87-210-051 Examine the Repaired Area

   1. Refer to Figure.

   2. Examine the repaired area to make sure that the bonds are satisfactory.

8. SUBTASK 72-32-87-350-055 Identify the Repair

   1. Make a mark, VRS1809, adjacent to the part number.

      1. Use the ink method.

         1. Refer to the SPM TASK 70-09-00-400-501.

Figure: Fan case liner panel - crack repair

Fan case liner panel - crack repair