S20-1 PAT325, Section 20, February 2004 Copyright 2004 MSC.Software Corporation SECTION 20 BASIC COMPOSITE PRODUCTION METHODS Vacuum port Bleeder cloth Peel ply Vacuum bag

S20-2 PAT325, Section 20, February 2004 Copyright 2004 MSC.Software Corporation

S20-3 PAT325, Section 20, February 2004 Copyright 2004 MSC.Software Corporation BACKGROUND n This Appendix is not intended to be a complete discussion of composite manufacturing, but a brief description of the typical procedure for a hand-made high quality component. n Alternative manufacturing methods include u Filament winding u Resin Transfer Molding (RTM) u …

S20-4 PAT325, Section 20, February 2004 Copyright 2004 MSC.Software Corporation MOLD TOOL PRODUCTION n Molds can be made from a variety of materials u Epoxy resin blocks u Reinforced composite u Wood u Plaster u Graphite Blocks u Metal n Mold tool treated with a release coating to prevent component sticking

S20-5 PAT325, Section 20, February 2004 Copyright 2004 MSC.Software Corporation COMPOSITE LAYUP n Individual plies of material added onto the mold n If a lot of plies are added the material is consolidated using a vacuum

S20-6 PAT325, Section 20, February 2004 Copyright 2004 MSC.Software Corporation CONSOLIDATION USING VACUUM Vacuum port Bleeder cloth Peel ply Vacuum bag n A layer of peel ply is applied over the component to prevent it from sticking to the vacuum bag. Peel ply may be a glass cloth coated with PTFE. n Sometimes a layer of bleeder cloth is placed over the peel ply to soak up excess resin n An impervious sheet or vacuum bag is applied over everything, and sealed around the edges. A vacuum is achieved by removing the air through a port.

S20-7 PAT325, Section 20, February 2004 Copyright 2004 MSC.Software Corporation CURING n The molded component is now cured, under pressure, in an oven or autoclave n After curing, vacuum bag materials are removed, and the component is removed from the mold. (Hopefully not with a chisel!)

S20-8 PAT325, Section 20, February 2004 Copyright 2004 MSC.Software Corporation