Preliminary Requirements

Safety Requirements

WARNING

IT IS THE RESPONSIBILITY OF THE OPERATOR TO OBTAIN AND OBSERVE THE MANUFACTURER'S MATERIAL SAFETY DATA SHEETS FOR CONSUMABLE MATERIALS. THESE CONTAIN INFORMATION SUCH AS, HAZARDOUS INGREDIENTS, PHYSICAL/CHEMICAL CHARACTERISTICS, FIRE, EXPLOSION, REACTIVITY, HEALTH HAZARD DATA, PRECAUTIONS FOR SAFE HANDLING, USE AND CONTROL MEASURES AND ALSO TO TAKE LOCAL REGULATIONS INTO CONSIDERATION.

Procedure

1. SUBTASK 70-36-08-380-001 Repair Local Voids In The Silicone Rubber

   1. Remove rubber from defective area.

      1. If it is necessary to remove the rubber down to the base metal or base composite material, remove old primer from the base metal or base composite material with No. 320 or finer grit aluminum oxide paper.

   2. Clean the repair area. Refer to SPM TASK 70-11-26-300-503.

   3. Let the part dry in ambient air for 15 minutes minimum.

   4. Apply CoMat 08-032 PRIMER to the base metal or base composite material where you removed the defective rubber down to the base metal or base composite material.

      1. NOTE

         If the removal of rubber from defective area did not go fully through the rubber to the base metal or base composite material of the part, it is not necessary to apply primer.

         Apply the primer to the base metal or base composite material only. Do not apply the primer to rubber surfaces.

   5. Fill the void area with the applicable silicone rubber compound from the subsequent list. Use the silicone rubber compound that is the same as the rubber that is on the part. Refer to the initial repair for the part.

      1. CoMat 08-038 SILICONE RUBBER COMPOUND.

      2. CoMat 08-150 SILICONE RUBBER COMPOUND.

   6. If you will use the oven cure procedure to cure the silicone rubber compound, clamp a Teflon-coated plate on the liquid rubber patch.

      1. For repairs of localized voids of 0.50 in. (12.70 mm) diameter maximum, the Teflon-coated plate is optional.

   7. Use one of these procedures to cure the silicone rubber compound. If plastic inner shroud material (ULTEM polyetherimide) is near the repair area, make sure that the adjacent heat source does not cause damage to the plastic inner shroud material.

      1. Oven Cure Procedure

         1. Bake the part at 290 deg F - 310 deg F (143 deg C - 154 deg C) for 1-2 hours.

      2. Heat Gun Cure Procedure

         1. Use a heat gun that is calibrated and demonstrated to heat the rubber surface to 290 deg F - 310 deg F (143 deg C - 154 deg C). If a calibrated heat gun is not available, use one of the heat guns in the subsequent list:

            1. Master appliance HG201A, vendor code 83284. Refer to V2500 Vendor List V2500-00-00-00-00-00A-00KA-D for the name and address of the source that this vendor code identifies.

            2. McMaster-Carr Supply 3149K11, vendor code 39428. Refer to V2500 Vendor List V2500-00-00-00-00-00A-00KA-D for the name and address of the source that this vendor code identifies.

         2. Cure rubber with the heat gun. Hold the heat gun approximately 2 in. (50.8 mm) away from the repair area for 10 minutes minimum.

         3. Lightly abrade the repair surface to blend.

         4. If necessary, do the above steps in this task again.

         5. Final cure with the heat gun for 15 minutes minimum at approximately 1 in. (25.4 mm) away from the repaired surface. The final cure must be tack-free.

   8. If there is a Teflon-coated plate on the repaired area, remove the Teflon-coated plate.

   9. Blend the repaired area.

   10. Do a check of the part to the initial repair.

   11. If machining is necessary, refer to the initial repair.