H

 

HAND LAY UP

The process of manually building up layers of fiberglass, with roll stock reinforcements and resin, using hand rollers, brushes and spray equipment.

 

HEAT DEFLECTION TEMPERATURE

The temperature at which the strength of a material begins to degrade as determined by ASTM D-2583. (Sometimes referred to as Heat Distortion Point).

 

HEAT-ACID RESIN

Polyester resin with exceptional fire qualities based chloridic acid.

 

HONEYCOMB CORE

Strips of paper, plastic, metal, etc., joined together to form a honeycomb pattern. Used as a lightweight core in sandwich moldings.

 

I 

 

IMPREGNATE

To saturate with resin. The most common application is saturating fiberglass with a catalyzed resin.

 

INHIBITOR

An additive to polyester resin or styrene used to slow the chemical reaction that leads to curing.

 

INSERT

A piece of material put into a laminate during or before molding to serve a definite purpose.

 

IN TUMESCENCE

A coating technology that causes the material to foam when exposed to heat, forming an insulating barrier to resist fire.

 

IN-SITU

In the position that it will finally occupy, e.g. molding or forming foam.

 

ISOPHTHALIC

A polyester resin based on isophthalic acid, generally higher in properties than a general purpose or orthophthalic polyester resin.

 

ISOTROPIC

The description of equal strength properties in all orientation. Isotropic composites are usually achieved by random fiber orientation.

 

J

 

JIG

Any fixture for holding parts in position, while joining them together or to maintain their shape

 

JOINT

A line or distinction formed when two panels are connected. Also referred to as a seam.

 

L

 

LAMINATE (noun)

Layers of a composite consisting of a resin and a reinforcement, bonded together to form a single structure.

 

LAMINATE

The act of processing resin and reinforcement into a bonded structure. Saturating glass reinforcement and rolling out air voids is to laminate.

 

LAYER

A single ply of lay up or laminate.

 

LAY-UP

The act of building up successive layers of polymer and reinforcement. Layers of catalyzed resin and fiberglass or other reinforcements are applied to a mold in order to make a part.

 

LOW-PRESSURE

Laminated, molded and cured using pressures from 400 psi down to and including the pressure obtained by the mere contact of the plies.

 

LOW PROFILE RESINS

Low shrink resins, that reduce surface distortion.