Plexiglas is a trade name for one of several acrylic sheets used as a transparent construction material, and it is a shatter-proof substitute for glass. It is produced in various thicknesses and tints. It can be cut with a metal saw, joined and sealed, drilled, ground and bent. Bending acrylic sheeting can be a very precise process using expensive technology and special heating elements, but for do-it-yourself projects, bending acrylic sheets can be accomplished with tools commonly found around many garages and with the help of an extra person.
Determine the angle of the bend you want. Mark the angle on the end of one of the boards, using the square and the protractor. Place a 2 by 4 board that is as long as your acrylic sheet flat along its 6-inch side and measure the angle from the base, intersecting the high corner. Mark the angle. You will trim off the base board with the table saw at this angle. If you are bending the acrylic at 90 degrees, there is no need to cut it. Set the table saw at the angle you have selected, and trim the edge of the base board.
Fit the 6-inch face of another 2 by 4 board that is as long as your acrylic sheet along the trimmed edge (or untrimmed if you desire 90 degrees). Screw the boards together through the second board straight into the base board, placing a screw every 6 inches. This is the completed form you will use to bend your acrylic sheet.
Mark your Plexiglas sheet along the line where you want to bend it. Ensure good ventilation, because heated acrylic creates mildly toxic fumes. Have another person hold the sheet on either side of the desired bend. Hold the heating gun approximately 4 inches from the line and direct the heat jet slowly back and forth along your line. The sheet will eventually soften along the bend line. Have the other person apply slight pressure as you slowly bend the sheet. Too much pressure will snap the sheet.
Place the bend line into the wooden form as it approaches your desired angle. Continue to direct the heat jet back and forth along the bend-line until the acrylic sheet fits into the form at the correct angle. Over-bend the sheet slightly to prevent “memory,” and then let the sheet relax back into the form. Hold the sheet in position for a few minutes, allowing it to cool and re-harden.