The Fabrication of Channel Letters in Los Angeles
A standard channel letter is a three-dimensional graphic sign element. Its channel is fabricated from sheet metal, most often aluminum since it will not rust. A flat sheet of aluminum is typically cut on a table by a computer-controlled router, laser, or water-jet, based on a vector-base art file (.cdr, .eps, .ai, .scv, .sci, or .fs). This creates the back of the channel and is the basis for the letter shape. The sides of the channel letter, called the returns, are then formed by bending a 3 to 6-inch-wide (150 mm)strip of aluminum sheet around the aluminum back. This return can be glue at the seam or flanged and riveted. The letter can is painted and fitted with any lighting components necessary such as neon gas tubes or light-emitting diode (LED) modules. A translucent plastic face usually of 3/16″ thick sheet acrylic or polycarbonate is cut to fit the open face of the letter can. A trim cap border is applied to its edges which gives the letter face a finished appearance and creates a fastening surface to attach it to the letter can. When illuminated at night, channel letters draw the eye of passers-by.
The face can also be applied with black perforated vinyl, so the letters appear black in the daytime and white when lit at night. For the best effect, face colors are usually matched with their closest corresponding LED color. A warm white LED is best used with a yellow or orange face. Since the advent of LED lighting technology, channel letters have become thinner in depth, decreasing to as shallow as 2″ to 3″ from 5″ to 6″, a trend which began in Europe, and is seen increasingly in the United States.
Exposed neon channel letter
These are standard channel letters, but the neon is covered with a clear acrylic face to keep birds from making a nest as well as to protect the exposed neon from outside elements, i.e., weather, etc. This allows for the exposed neon to be seen, as well as the inside of the channel letter interior itself to add to the dimensional look.
Front-lit Channel Letters
In this type of letter, the face of the letters is constructed from acrylic and the lighting is directed to the front of the letter. The LED’s or neon are located inside the can of the letter. The can(the structure) of the letter is fabricated from aluminum. There is various color options on the lighting of the letters. This can achieve by using translucent vinyl on the acrylic face or using different color lighting on the LED’s. The depth of the letters can range from 3-5 inches. A trim cap( a piece of plastic molding) is used to attach the outer edges of the acrylic face to the aluminum can of the letter.
Back (Halo)-lit or reverse-lit letters
In this letter type, the face of the letter is constructed from aluminum and the lighting is directed to the back. This light floods the wall that the letter is mounted to and creates a negative space at night. Letters in this style are also called halo letters. It is usually the most expensive form to manufacture. LEDs are installed to the inside back of the can, and the back is often fitted with a clear or translucent plastic back to diffuse the light and protect the lighting elements and wiring. The letters are typically mounted 1-1/2″ from the wall so they are set off from the façade of the building. The inside of the can is often painted white to reflect light. The effect of the halo lighting allows for a variety of creative effects depending on the color, sheen, and texture of the building surface. Light-colored building surfaces with a matte finish produce the best halo effect; dark mirror-like finishes the worst.
Front and Back (Halo)-lit channel letters
These letters combine the same features of a front and back-lit channel letter. The letters are lit from the front of the face as well from the back of the letter.