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/m3 total dust, and 5 mg/m3 respirable dust. The ACGIH TLV/TWA for particles (insoluble or poorly soluble) not otherwise specified is 10 mg/m3 inhalable particulate and 3 mg/m3 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.
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.