(c)  
Use the solvent and a wiping cloth to clean the damaged area.

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MAINTENANCE MANUAL

 S 348-007
 (6)  Cut a piece of the Fiberglass or Kevlar cloth that is 3-inches wide and long enough to go around the duct a minimum of two times.
 E. Repair the Taped Joint
 S 348-008
 (1)  
Apply a thin, smooth layer of primer to the duct joint area and let it dry at room temperature for a minimum of 1 hour.

 S 348-009

 (2)
Apply the sealant to one side of the Fiberglass or Kevlar cloth.

 S 348-010

 (3)  
Wind the Fiberglass or Kevlar cloth around the duct joint a minimum of two times.

 NOTE: Make sure the sealant on the Fiberglass or Kevlar cloth is in
____
 contact with the duct.

 S 348-011
 (4)  Put a piece of plastic sheet on the Fiberglass or Kevlar cloth and press lightly with a squeegee or with your hand.
 NOTE: Make the Fiberglass or Kevlar cloth smooth from the center to
____ the edges of the cloth to remove any bubbles or any wrinkles and to remove unwanted resin.
 S 348-012
 (5)  
Remove the plastic sheet from the Fiberglass or Kevlar cloth and remove unwanted resin with a wiping cloth.

 S 348-013

 (6)  
Wrap pressure sensitive glass cloth tape around the two edges of the cloth repair.

 NOTE: Make sure the tape lies flat with no wrinkles or gaps.
____
 F. Put the Airplane Back to Its Usual Condition
 S 428-068
 (1)  If insulation was removed from the duct joint, install new
 insulation.

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MAINTENANCE MANUAL

 S 418-015
 (2)  Install the panels or other airplane structure removed to gain access to the duct joint.
 TASK 21-23-02-308-016
 3. Fiberglass or Kevlar Duct - External Patch Repair (Fig. 801)
_________________________________________________
 A. General
 (1)  
This procedure gives instructions for the repair of a crack or cut in a fiberglass or Kevlar air conditioning duct with an external patch.

 (2)  
An external patch is applicable when the cut or crack is less than 1/4 inch wide and 3 inches long.

 B. Consumable Materials
 (1)  
Fiberglass cloth - minimum 0.007 inch thick (MIL-C-9084 Type VIII) -commercially available

 (2)  
Kevlar cloth - minimum 0,007 inch thick (alternative to the Fiberglass cloth)

 (3)  
Plastic sheet - polyethylene or vinyl (commerically available)

 (4)  
Resin for repair of Fiberglass duct - R109A Hetron 92 Polyester

 (5)  
Resin for repair of Kevlar duct - BMS 8-201 Type II (Epocast 50-A)

 (6)  
Sandpaper - 320 grit (commerically available)

 (7)  
Solvent - Butyl carbitol (alternative to B01011, Series 91) -commerically available (AMM 20-30-91/201)

 (8)  
Solvent - B01011, Series 91 - commercially available (AMM 20-30-91/201)

 (9)  
Squeegee - commercially available

 (10)
 Wiping cloth, lint-free (commerically available)

 C. References
 (1)  AMM 36-00-00/201, Pneumatics - General
 D. Prepare for the Repair
 S 868-043
 (1)  
Remove the pneumatic power (AMM 36-00-00/201)

 S 868-044

 (2)  
On the bleed air control module on the pilots' overhead panel, put the pack control switches in the OFF position.

 S 018-046

 (3)  
Remove the applicable ceiling, sidewall, or floor panels to gain access to the damaged air conditioning duct.

 (4)
If insulation is installed on the duct, remove the insulation.
　
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