Installation Guide

4
CUTTING PLEXIGLAS
®
ACRYLIC SHEET
Health and Safety Precautions
Cutting Plexiglas
®
acrylic sheet may cause localized heating,
resulting in the release of methyl methacrylate (MMA) monomer
vapor, and may also generate some polymer dust. See Concentration
Levels and Ventilation Standards, page 3. Any dust produced by
the cutting of Plexiglas
®
acrylic sheet is considered “nuisance”
dust. The OSHA PEL/TWA for nuisance dusts is 15 mg/m
3
total
dust, and 5 mg/m
3
respirable dust. The ACGIH TLV/TWA for
particles (insoluble or poorly soluble) not otherwise specified
is 10 mg/m
3
inhalable particulate and 3 mg/m
3
respirable
particulate. Worker exposure to dust can be controlled with
adequate ventilation, vacuum dust removal at the point of
generation, or the use of suitable protective breathing devices.
Cutting
Plexiglas
®
acrylic sheet may be cut by sawing or routing with
power equipment saws or by scribing and breaking. Scribing is
limited to straight cuts in thin pieces of Plexiglas
®
acrylic sheet,
0.236 inches or less, and is practical for use by the craftsman
who has no power tools when cutting small quantities of sheet
material. Sawing and routing may be used for straight and
curved cuts on any thickness of material. Keep masking intact
during fabrication to protect the surfaces and provide lubrication.
Plexiglas
®
acrylic sheet is a combustible thermoplastic material.
Observe fire precautions appropriate for comparable forms of
wood and paper products.
The kind of cutting to be done on Plexiglas
®
acrylic sheet
should determine the type of sawing equipment to be used.
Circular blade saws are limited to straight cuts; scroll and sabre
saws for rough cutting small-radius curves in thin Plexiglas
®
acrylic sheet; band saws for rough cutting larger-radius curves or
for making rough straight cuts in thick Plexiglas
®
acrylic sheet.
Routers and woodworking shapers are used for cutting and
trimming the edges of flat and formed parts of any configuration
and provide the best overall fabricated edge.
Circular Blade Saws
There are several types of circular blade saws suitable for cutting
Plexiglas
®
acrylic sheet. Table saws vary in size from small,
light-duty models to large, heavy-production models and are
generally used for cutting Plexiglas
®
acrylic sheet to close
dimensions. The size of table saw most commonly used is a
medium-duty model with an arbor of
5
⁄
8
to 1 inch diameter and
powered by a 1.5 to 5hp motor. Special fixtures are often used
to hold the work steady for accurate cutting.
Radial saws and swing saws move while the work is held
stationary and are generally used to make angle cuts and cross
cuts in narrow pieces of Plexiglas
®
acrylic sheet. The length of
cut of a radial saw is limited to about 24 inches.
Panel saws are of two types. The first has the saw blade and
motor mounted above the material to be cut. The work is placed
on the table against a fence and the saw is fed through the work.
The second type has the saw blade and motor mounted below the
material to be cut with a combination saw guard and hold-down
bar. The blade extends through the table high enough to cut
through the material. This type of panel saw is usually set so that
the saw blade must be retracted before the saw guard and
hold-down bar can be released. These saws are available with
either horizontal or vertical tables. The vertical saws offer
advantages in that less floor space is needed; large sheets of
Plexiglas
®
acrylic sheet may be placed on the saw more easily;
and there is less danger of scratching unmasked sheets of
Plexiglas
®
acrylic sheet.
Circular saws should have motors with sufficient power. A
10-inch-diameter saw should be powered by approximately a
2 hp motor; a 14-inch-diameter saw, by approximately a 5 hp motor.
Blades are normally driven direct and run at a motor speed of
3,450 rpm. Saws should be equipped with heavy-duty, production-
type fences, be well-guarded and have sawdust-removal systems.
Kick-plate switches and electromechanical or frictionless electronic
motor brakes should be provided for safety purposes.
Programmable horizontal and vertical panel saws with a
movable fence can be used to cut Plexiglas
®
acrylic sheet to size
in high-production operations.