TABLE OF CONTENTS Cutting and manual ply collation are the major cost drivers in composite part fabrication, normally accounting for 40 60% of the cost, depending on part size and complexity. Ply collation can be accomplished by hand, automated tape laying, filament winding, or fiber placement. Hand lay-up is generally the most labor intensive method, but may be the most economical, if the number of parts to be built is limited, the part size is small, or the part configuration is too complex to automate. Automated tape laying is advantageous for flat or mildly contoured skins, such as large thick wing skins. Filament winding is a high rate process that is used primarily for bodies of revolution or near bodies of revolution. Fiber placement is a hybrid process that possesses some of the characteristics of automated tape laying and filament winding. It was developed to allow the automated fabrication of large parts that could not be fabricated by either tape laying or filament winding.
Manual hand collation is conducted using either prepreg tape (24 in. maximum width) or broadgoods (60 in. maximum width). Prior to actual lay-up, the plies are usually precut and kitted into ply packs for the part. The cutting operations are normally automated unless the number of parts to be built does not justify the cost of programming an automated ply cutter. However, if hand cutting is selected, templates to facilitate the cutting operation may have to be fabricated. If the lay-up has any contour...
