Glossary
ACCELERATOR
Liquid or powder which decreases the curing time of a synthetic resin.
ACETONE
Cleaning agent
AIR INHIBITION
Undercuring of exposed resin surface. Sticky.
BINDER PVA
Emulsion or powder used to hold chopped strands together
BLISTER
Moulding flaw where air or water is trapped
BLANK
A ready shaped foam core requiring application of FRP to complete
BONDING
The joining of two panels by an FRP joint cured in situ, or of two layers of FRP
CARBON FIBRE
A light weight, high-tech reinforcement
CHOPPED STRAND MAT
A lightly compressed and bound mat formed from filaments of glass which have been chopped to short
lengths and bound together
CATALYST
A chemical which initiates polymerisation of a resin
CURE
Chemical hardening of the resin mixture
COBALT ACCELERATOR
Chemical additive to accelerate curing based on cobalt naphthanate
CORE
Foam or wood layer between inner and outer FRP skins
COMPRESSIVE STRENGTH
Ability of laminate to withstand crushing
CONSOLIDATING (a laminate)
Wetting out and removing air bubbles from resin/glass layer
CONTACT MOULDING
Casting of FRP by the use of a mould
DELAMINATION
Separation of one layer of a cured laminate from another
DRY LAMINATE
Resin to glass ratio below specification
EPOXY
Resin with adhesive, resistance and stability qualities superior to polyester
EXOTHERM
Heat generated during curing process
FEMALE MOULD
Mould where contact laminating is on the inside
FILLER
Inert material which reduces the volume of resin
FILLET
Bead of filled resin at a joint
FLEXURAL STRENGTH
A measure of bending resistance
FLOWCOAT
Gelcoat with high wax content for cosmetic finishes
FOAM
Lightweight, aereated plastic core material
FORMER
Non-structural item to give shape to panel stiffeners
FRP
Fibre reinforced plastics
GEL TIME
Interval between adding catalyst and laminate becoming hard
GELCOAT
Viscous, coloured resin used to give smooth outer hull skin
GRP
Glass reinforced plastics
HARDENER
Catalyst
HAND LAYUP
Hand applied resin and glass laminate
HONEYCOMB CORE
Cardboard or aluminium frame spacing core material
HOT MIX
Over-catalysed resin mix
ISOPHTHALIC
Improved polyester with good wear and flexibility properties
INJECTION MOULDING
Introduction of resin to reinforcement pre-applied between matched male and female moulds
LAMINATE
Consolidated and cured layers of FRP
LAY UP
The moulding process
KEVLAR
High tech aramid fibre reinforcement
MALE MOULD
Mould where the FRP is laid up on the outside of the mould
MONOMER
Styrene monomer. Liquid thinner, gives characteristic smell
MATURING TIME
Follows gel stage. Up to 3 weeks
MEKP
Methyl ethyl ketone peroxide. Standard catalyst
MOULD
Tool in which FRP is cast
POLYMER
Fundamental molecular chain formed when FRP chemical reaction is initiated
PVA
Polyvinyl alcohol. Basic release agent
PLUG
Original and faithful pattern used to cast mould
POLYESTER
Basic resin component of FRP
POLYURETHANE FOAM
Orange or cream coloured rigid foam. Friable
POLYSTYRENE FOAM
White colour, for insulation. Large beads
PVC FOAM
Polyvinyl choride foam. Flexible, high quality
POTLIFE
Interval between addition of catalyst to resin and hardening
PRE-PREG
Previously impregnated reinforcement
PIGMENT
Colouring agent for resins
PRE-ACCELERATED
Resin with accelerator added precisely at chemical works
RESIN
Viscous liquid component of FRP system
RELEASE
Removal of moulded unit from mould
RELEASE AGENT
Liquid or wax compound to ease release
RESIN RICH
Resin ratio higher than specification
ROVINGS
Continuous strands of glass loosely bound together
ROLLER
Tools for compacting laminate and applying resin
RESIN PUTTY
Heavily filled resin mix, paste like
SHELF LIFE
Length of time material remains useable while in store
SANDWICH CONSTRUCTION
Double skin moulding with core material separating skins
SCRIM
Open weave cloth used to bind other type of cloth
STIPPLING
Use of paint brush to chase out individual air bubbles from laminate
SHEATHING
Application of FRP skin to previously existing item
SPLIT MOULD
Mould in more than one piece
SPRAY LAY-UP
Application of chopped roving and resin by spray gun
SURFACE TISSUE
Fine cloth applied after gel coat
SQUEEGEE
Alternative tool for laminating
TENSILE STRENGTH
A measure of strength in tension
THIXOTROPIC
A liquid of high viscosity
TWO-PART MIX
Two liquids requiring mixing together to cure
TOOLING
The plugs and moulds
UNIDIRECTIONAL
One-way. Unidirectional rovings-sheet of roving loosely bound as cloth
VACUUM BAGGING
High tech-method of applying pressure to laminate in order to achieve high quality bond
VINYL ESTER RESIN
With qualities superior to polyester
WETTING OUT
Process of applying resin to reinforcement
WARP
Transverse strand of a cloth
WEFT
Lengthways strand of cloth
WOVEN ROVINGS
Cloth woven from rovings
