Fabricate - To work a material
into a finished form by machining, forming, or other
operation or to make flexible film or sheeting into
end products by sewing, cutting, sealing, or other operation.
Family mold (injection) - A multi-cavity mold where each of the cavities forms
one of the component parts of the assembled finished
object.
Fiber - This term usually
refers to relatively short lengths of very small cross-sections
of various materials. Fibers can be made by chopping
filaments (converting). Staple fibers may be 1/2 to
a few in length and usually 1 to 5 denier (1/2 to 1
in diameter in Marlex polyethylene).
Fiber Show - Strands or
bundles of fibers that are not covered by resin and
that are at or above the surface of a reinforced plastic.
Filament - A variety of
fiber characterized by extreme length, which permits
its use in yarn with little or no twist and usually
without the spinning operation required for fibers.
Filament Winding - Roving
or single strands of glass, metal, or other reinforcement
are wound in a predetermined pattern onto a suitable
mandrel. The pattern is so designed as to give maximum
strength in the directions required. The strands can
either be run from a creel through a resin bath before
winding or preimpregnated materials can be used. When
the right number of layers have been applied, the wound
mandrel is cured at room temperature or in an oven.
Fill Point - The level to
which a container must be filled to furnish a designated
quantity of the content.
Fill-and-wipe - Parts are
molded with depressed designs; after application of
paint, surplus is wiped off, leaving paint remaining
only in the depressed areas.
Filler - A cheap, inert
substance added to a plastic to make it less costly.
Fillers may also improve physical properties, particularly
hardness, stiffness, and impact strength. The particles
are usually small, in contrast to those of reinforcements
but there is some overlap between the function of the
two.
Fillet - A rounded filling
of the internal angle between two surfaces of a plastic
molding.
Film - An optional term
for sheeting having a nominal thickness not greater
than 0.010 inch.
Fin - The web of material
remaining in holes or openings in a molded part which
must be removed in finishing.
Finish - The plastic forming
the opening of a container shaped to accommodate a specific
closure. Also, the ultimate surface of an article.
Finish Insert - A removable
part of a blow mold to form a specific neck of a plastic
bottle. Sometimes called Neck Insert.
Fish Eye - A fault in transparent
or translucent plastics materials, such as film or sheet,
appearing as a small globular mass and caused by incomplete
blending of the mass with surrounding materials.
Flake - Used to denote the
dry, unplasticized base of cellulosic plastics.
Flame Retardant Resin -
A resin which is compounded with certain chemicals to
reduce or eliminate its tendency to burn. For polyethylene
and similar resins, chemicals such as antimony trioxide
and chlorinated paraffins are useful.
Flame Spraying - Method
of applying a plastic coating in which finely powdered
fragments of plastic, together with suitable fluxes,
are projected through a cone of flame onto a surface.
Flame Treating - A method
of rendering inert thermoplastic objects receptive to
inks, lacquers, paints, adhesives, etc. in which the
object is bathed in an open flame to promote oxidation
of the surface of the article.
Flammability - Measure of
the extent to which a material will support combustion.
Flash - Extra plastic attached
to a molding along the parting line; it must be removed
before the part can be considered finished.
Flash Gate - A long, shallow
rectangular gate.
Flash Line - A raised line
appearing on the surface of a molding and formed at
the junction of mold faces.
Flash mold - A mold designed
to permit excess molding material to escape during closing.
Flash Point - The lowest
temperature at which a combustible liquid will give
off a flammable vapor that will burn momentarily.
Flexible Molds - molds made
of rubber or elastomeric plastics used for casting plastics.
They can be stretched to remove cured pieces with undercuts.
Flexural Modulus - A measure
of the strain imposed in the outermost fibers of a bent
specimen.
Flexural Strength - The
strength of a material in blending, expressed as the
tensile stress of the outermost fibers of a bent test
sample at the instant of failure. With plastics, this
value is usually higher than the straight tensile strength.
Flock - Short fibers of
cotton, etc., used as fillers for molding materials.
Flocking - A method of coating
by spraying finely dispersed powders or fibers.
Flow Line - A mark on a
molded piece made by the meeting of two flow fronts
during molding.
Flow Marks - Wavy surface
appearance of an object molded from thermoplastic resins
caused by improper flow of the resin into the mold.
Fluidized Bed Coating -
A method of applying a coating of a thermoplastic resin
to an article in which the heated article is immersed
in a dense-phase fluidized bed of powdered resin and
thereafter heated in an oven to provide a smooth, pin-hole-free
coating.
Fluorescent Pigments - By
absorbing unwanted wavelengths of light and converting
them into light of desire wavelengths, these colors
seem to have an actual glow of their own.
Fluorine - The most reactive
non-metallic element. A pale yellow gas which is both
corrosive and poisonous, it reacts vigorously with most
oxidizable substances at room temperature, and forms
fluorides. It is used in the production of metallic
and other fluorides, some of which are used to introduce
fluorine into organic compounds, i.e., the fluorocarbons.
Fluorocarbon Plastics -
Plastics based on polymers made with monomers composed
of fluorine and carbon only.
Fluorocarbons - The family
of plastics including polytetrafluoroethylene (PTFE);
polychlorotrifluoroethylene (PCTFE); polyvinylidene
and fluorinated ethylene propylene (FEP). They are characterized
by properties including good thermal and chemical resistance
and nonadhesiveness, and possess a low dielectric constant.
Depending upon which of the fluorocarbons are used,
they are available as molding materials, extrusion materials,
dispersions, film or tape.
Fluoroplastics - Plastics
based on polymer with monomers containing one or more
atoms of fluorine or copolymers of such monomers with
other monomers, the fluorine containing monomer(s) being
in greatest amount by mass.
Foaming Agents - Chemicals
added to plastics and rubbers that generate inert gases
on heating, causing the resin to assume a cellular structure.
Foil Decorating - molding
paper, textile, or plastic foils printed with compatible
inks directly into a plastic part so that the foil is
visible below the surface of the part as integral decoration.
Force Plate - The plate
that carries the plunger of force plug of a mold and
guide pins and bushings. Since it is usually drilled
for steam or water lines, it is also called the Steam
Plate.
Force Plug - The portion
of a mold that enters the cavity block and exerts pressure
on the molding compound, designated as Top Force or
Bottom Force by position in the assembly; also called
Plunger or Piston.
Formaldehyde - A colorless
gas (usually employed as a solution in water) which
possesses a suffocating, pungent odor. It is derived
from the oxidation of methanol or low-boiling petroleum
gases such as methane, ethane, propane, and butane.
It is widely used in the production of phenol formaldehyde
(phenolic), urea formaldehyde (urea), and melamine formaldehyde
(melamine) resins.
Friction Coefficient - A
number expressing the amount of frictional effect.
Friction Welding - A method
of welding thermoplastics materials whereby the heat
necessary to soften the components is provided by friction.
Furan Resins - Dark colored,
thermosetting resins available primarily as liquids
ranging from low-viscosity polymers to thick, heavy
syrups. |