The table saw is the workhorse in any woodworking shop. With the proper accessories and adjustments it will cut straight every time. Typical table saws have a short tabletop and no support for the out-feed material. The table saw design seems to require that users have an assistant when working with large sheet goods. Most woodworkers are alone in the shop so they need to rig up some way to support pieces. A table saw extension will allow you to work more efficiently and free up floor space in the shop. Adding accessory tables can make the task of cutting large sheets by yourself easier and safer.
Put on safety glasses.
Measure the width of your table saw. This will be the dimension of the extension table. Measure the height of your saw on all four corners to check that it is level, and shim as required.
Build a torsion box 2 inches thick by at least 16 inches deep while the width of the extension table will be determined by the width of the table saw's table.
Build four legs to support the extension table and attach. You can do this by cutting 4-inch strips of 3/4-inch plywood; it will require eight pieces the length of your saw's height minus 1/4 inch. Glue two pieces together along the length to make an L shape.
Attach the legs to the torsion table with glue and screws.
Place the extension table next to the saw where it will be located. Using a straight edge, and mark the locations of the miter slots on the extension table.
Clamp a straight edge to the table as a guide for your router. Now use the router to mill out the miter slots in the extension table to match the ones on the table saw.
Cut and attach the 1/4-inch Masonite to the new table; the Masonite acts as a slick surface to work on and is easily replaced if damaged.