Nylon or polyester peel ply is laid on the outer surface of a composite layup and cured with it. When ripped off, it fractures the resin surface, leaving a fresh, rough and uncontaminated bonding area. Some peel plies leave release residue that hurts adhesion, so the type is specified and often followed by light abrasion. It must stay on until right before bonding.
Leave the peel ply on the spar cap until the adhesive's mixed, then strip it and bond within the hour.
Also heard as
- tear ply
- peel cloth
Related terms
Scuff
To roughen a bonding surface lightly with an abrasive pad or paper to remove gloss and contamination.
Mechanical interlock
Adhesion gained by adhesive flowing into pores and roughness and locking in once it hardens.
Adhesive failure
A break at the interface between adhesive and part, leaving one surface clean or nearly clean.
Kissing bond
A bond where adhesive and part are in full contact but have little or no real adhesion.