Home Built Hot
Wire CNC Foam cutter
Day 1 - Vertical Y Axis
Day 2 - Horizontal X Axis
Day 3 - Lead Screw
Day 4 - Electronics
Day 5 - Finalizing the machine
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Foam Cutting Services - EPP, EPS, XPS
All About Foam Forum -
Composites Prototyping and Design
Large and Configurable CNC Machines
How to coat EPS foam (Crown Moldings)
How to build an EPS Foam Recycler
How to build an EPS base and Cap
How is EPS manufactured - molded
How to make RC foam planes
How to cut EPS, XPS, EPP foam
How to cut Polyurethane foam ( PU )
How to cut Acrylics - Laser cutting
What is - more info about foam
What is EPS foam
What is XPS foam
What is EPP foam - Expanded Polypropylene
What is PE foam - Polyethylene foam
What is Polyurethane foam
What is Memory Foam
EPS foam (Expanded Polystyrene Foam)
Polystyrene is a polymer made from
the monomer styrene, a liquid hydrocarbon
that is commercially
manufactured from petroleum by the chemical industry.
At room temperature,
polystyrene is normally
a solid thermoplastic, but can
be melted at higher temperature for molding or
extrusion, then resolidified.
Styrene is an aromatic monomer, and polystyrene is an aromatic polymer.
Polystyrene was accidentally discovered in 1839 by Eduard Simon an
apothecary in Berlin, Germany.
From storax, the resin of Liquidambar
orientalis, he distilled an oily
substance, a monomer which he named styrol.
Several days later Simon found that the styrol had thickened, presumably
oxidation, into a jelly he dubbed
styrol oxide ("Styroloxyd"). By 1845
English chemist John Blyth and German
chemist August Wilhelm von Hofmann
showed that the same transformation of styrol took place in the absence of
They called their substance
metastyrol. Analysis later showed that it was chemically
identical to Styroloxyd.
In 1866 Marcelin Berthelot correctly
identified the formation
of metastyrol from styrol as a polymerization process.
About 80 years went by before
realized that heating of styrol starts a chain reaction which produces
macromolecules, following the thesis of German
organic chemist Hermann
Staudinger (1881 - 1965). This eventually led to the
substance receiving its present
name, polystyrene. The I.G. Farben company began manufacturing polystyrene in
about 1931, hoping it would be a suitable replacement for
die cast zinc in many
applications. Success was
achieved when they developed a
reactor vessel that extruded polystyrene through
a heated tube and cutter,
producing polystyrene in pellet form.
Pure solid polystyrene is a colorless, hard plastic with limited flexibility. It
cast into molds with fine detail.
Polystyrene can be transparent or can be made
to take on various colors. It is
economical and is used for
producing plastic model
assembly kits, plastic cutlery, CD "jewel" cases, and
many other objects where a
fairly rigid, economical plastic of any of various colors is desired.
Polystyrene's most common use, however, is as expanded polystyrene (EPS).
is produced from a mixture of about 90-95% polystyrene
and 5-10% gaseous blowing
commonly pentane or carbon dioxide.
The solid plastic is
expanded into a foam
through the use of heat, usually steam.
Extruded polystyrene (XPS), which is
different from expanded
is commonly known by the trade name Styrofoam. The voids
filled with trapped air
give it low thermal conductivity. This makes it ideal as a construction material
it is therefore
sometimes used in structural insulated panel building systems. It is
as insulation in building
structures, as molded packing material for
cushioning fragile equipment inside
boxes, as packing "peanuts",
architectural structures (such as pillars), and also in
crafts and model building,
particularly architectural models. Foamed between two sheets of paper, it makes
substitute for corrugated cardboard, tradenamed Fome-Cor. A
more unexpected use
for the material
if as a lightweight fill for embankments
in the civil engineering industry.
Expanded polystyrene used to contain CFCs, but other, more environmentally-safe
are now used. Because it is an aromatic hydrocarbon, it burns with
orange-yellow flame, giving
off soot, as opposed to non-aromatic hydrocarbon
polymers such as polyethylene,
which burn with a light yellow flame.
Production methods include sheet stamping (PS) and injection molding (both PS
The chemical makeup of polystyrene is a long chain hydrocarbon with every other
connected to a Phenyl group (an aromatic ring similar to benzene).
EPS foam can be molded into different shapes -
1. EPS blocks are usually 4' x 3' x 8' or 4' x 4' x 8'
2. EPS shapes (molded)
Cutting EPS foam
Expanded polystyrene is very easily cut with a hot-wire foam cutter, which
is easily made
by a heated and taut length of wire, usually nichrome due to nichrome's
oxidation at high temperatures and its suitable electrical conductivity. The hot
foam cutter works by heating the wire to the point where it can vaporize foam
adjacent to it. The foam gets vaporized before actually touching the heated
which yields exceptionally smooth cuts.
Polystyrene, shaped and cut with hot wire foam cutters, is used in architecture
actual signage, amusement parks, movie sets, airplane construction, and much
Such cutters may cost just a few dollars (for a completely manual cutter) to
thousands of dollars for large CNC machines that can be used in high-volume
Polystyrene can also be cut with a traditional cutter. In order to do this
the sides of the blade one must first dip the blade in water and cut with the
an angle of about 30º. The procedure has to be repeated multiple times for best
Polystyrene can also be cut on 3 and 5-axis CNC routers, enabling large-scale
prototyping and model-making. Special polystyrene cutters are available that
look more like large cylindrical rasps
Where to buy EPS foam - Click here