Acrylic sheet can be cut in three ways:
3) Scribing and breaking
Sawing and routing can be used for straight and curved cuts on any thickness of material. Scribing is limited to straight cuts in thin pieces of sheet .236 inches or less in thickness. It is practical for craftsmen who do not have power tools and for cutting small quantities of sheet material.
The kind of cutting to be done will determine the type of sawing equipment you will need. Circular blade saws are limited to straight cuts. Scroll and sabre saws are good for rough cutting small-radius curves in thin Plexiglas® acrylic sheet and band saws are good for rough cutting larger-radius curves. Band saws can also be used for making rough straight cuts in thick sheets.
Routers and shapers are used for cutting and trimming the edges of flat and formed parts of any configuration. They provide the best fabricated edge. This article will focus on sawing, and specifically, with a circular blade saw.
Types of circular blade saws
Table Saws. Table saws vary in size from small, light-duty models to large, heavy-production models and are generally used for cutting sheet to close dimensions. The most commonly used table saw is a medium-duty model with an arbor of 5⁄8 to 1 inch diameter. These saws are typically powered by a 1.5 to 5hp motor. Special fixtures will be necessary to hold the work steady for accurate cutting.
Radial Saws. 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. The length of cut of a radial saw is limited to about 24 inches. These are also known as chop saws.
Panel Saws. 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. 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.
Panel saws are available with either horizontal or vertical tables. The vertical saws take up less floor space and large sheets can be placed on the saw more easily. And there is less danger of scratching unmasked sheets of Plexiglas® acrylic sheet with vertical saws. Panel saws are found in high production shops. and not suitable for the hobbyist. Below is an image of a panel saw.
Choosing the right blade.
For best results, saw blades should be equipped with teeth of the triple-chip style. This tooth style is also called "square" and "advanced". Triple-chip-style blades are designed so that alternate teeth start and finish the cut. The square tooth corners are slightly chamfered minimizes chipping. These blades are also available as carbide-tipped. Carbide tipped blades make faster, superior quality cuts, and require fewer blade changes. However, carbide blades must be returned to the factory for resharpening.
Where the quantity of sheet to be cut is low or there are budgetary constraints, high-speed steel blades may be used instead. These blades are made of alloy steel. They are tempered to permit filing. The teeth should have a positive rake angle of 0° to 10° and should be of uniform height and shape. When cutting 0.150 inches or thinner sheet, the blade should be hollow ground rather than set. Teeth of uneven height will cause chipping and stress a few teeth instead of spreading the load to all the teeth.
For cutting very small quantities, standard hollow ground fine-tooth blades used for cross cutting wood or ply-tooth blades may be used. Below is the recommended high-speed steel circular saw blade information for cutting various thicknesses.
To minimize chipping and overheating, saw blades should not protrude more than 1⁄2 inch beyond the thickness of the sheet.