Extra 200 - Page 264

CHAPTER 51
PAGE 21
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RA - FLUGZEUGBAU GmbH
SERVICE MANUAL EXTRA 200
PAGE DATE: 1. July 1996
to the repair area and lay on fabric in accordance to the layer
sequence plans. Ensure to use correct style and direction of
fabric.
I M P O R T A N T Repair area must be clean of dirt, dust and grease!
Lay out the required number and size of fabric pieces on a
piece of colored plastic foil and soak (wet) them with resin
mixture, subsequently position them on the repair area.
I M P O R T A N T Remove the plastic foil after each positioning process.
For a repair of honeycomb sandwich parts you have to
observe the following: The repair area has to be cured under
condition of vacuum bagging.
For vacuum bagging, proceed as follows:
- Apply peel nylon fabric on the last repair fabric layer
- Perforate a clean, thin plastic foil with a thick needle
(max. spacing of holes: 20mm x 20mm) - mainly in the
area of the honeycomb - and lay it on the repair area.
- Lay a jute cloth (weave) or equivalent bleeder cloth on
this perforated plastic foil.
- Lay an air tight plastic foil upon the jute weave and seal
their edges to the surrounding surface using an adhesive
tape.
- Apply suction with a vacuum pump (pressure approx.
0.7 bar/ 10 psi)
- Apply the thermal curing cycle. (Refer to Figure 3)
- Following the curing cycle remove vacuum bagging
material and peel nylon fabric.
After the pre-curing period at room temperature, the re-
paired area has to be cured according the temperature cycle
as shown on Figure 6.
REP
AIRS
Repair of Sandwich Material