Channel Letter Sign Construction

Signs Manufacturing builds dimensional channel letter signs for businesses throughout Dallas–Fort Worth. This guide explains the construction details behind our signs, including letter depth, computer-controlled fabrication, aluminum backs, welded assemblies, drainage, and backplates.

The final construction depends on the letter size, lighting style, building surface, and project requirements. Our design team can help you compare the options for your sign.

What Are Channel Letter Returns?

The returns are the sidewalls of each dimensional letter. Return depth is the front-to-back dimension of the letter body—for example, 3 inches or 5 inches. In a front-lit letter, the returns surround the lighting components between the letter back and translucent face.

Return depth is different from wall standoff: the space between the back of the letter and the mounting surface. That separation is especially important for reverse-lit and front-and-back-lit letters, where light shines onto the wall or backplate.

How Letter Depth Affects Appearance and Lighting

• Dimensional appearance: Deeper returns give letters a more substantial profile and more pronounced daytime shadows, particularly when viewed from an angle.
• Lighting layout: More space between LEDs and a translucent face can help light spread evenly. The result also depends on LED optics, module spacing, letter stroke width, and face material; greater depth alone does not guarantee a brighter or more evenly lit sign.
• Design proportions: Return depth should suit the letter height and the building. Shallow letters can be appropriate for small lettering or a slim architectural appearance.
• Visibility: Letter height, contrast, typeface, placement, and illumination all affect readability. Additional depth primarily changes the dimensional profile.

Our Return-Depth Recommendations

Signs Manufacturing generally recommends 5-inch returns for typical storefront channel letters. Very large letters may need deeper returns, while small lettering may be better suited to 3-inch returns.

Reverse-lit letters often use 3-inch returns and are mounted away from the wall on spacers. HALO-RING™ and front-and-back-lit channel letters are evaluated according to their lighting design and size.

Halo illumination: The width and appearance of the glow depend on wall standoff, LED placement, the letter design, and the color and texture of the surface behind the sign. Return depth and wall standoff should be considered separately.

Our sales consultants and design team can recommend dimensions for your project. Visit our sign showroom to compare illuminated letter styles in person.

Computer-Controlled Cutting and Forming

Our fabrication process starts with computer-prepared letter patterns. Full-size paper installation patterns help installers position the letters with the intended alignment and spacing.

Computer-controlled routing equipment cuts metal letter backs, plastic faces, and aluminum backplates to the designed shapes. Precision forming equipment shapes the returns to match the cut components, helping produce consistent contours and aligned bends.

Signs Manufacturing commissioned the development of a computer-controlled precision letter-forming machine. Automated cutting and forming help us produce accurately fitted components and consistent letter shapes.

Virtually all of our metal and plastic cutting and forming equipment is computer controlled. This helps maintain accuracy when assembling the letter backs, returns, and faces.

Aluminum Backs and Welded Construction

Our channel letter backs are constructed from 0.063-inch-thick or heavier 3003-H14 aluminum. The material and thickness are selected for the letter size and design. Aluminum does not develop the iron rust associated with steel, although it can corrode in some conditions.

Machine forming allows us to work with the specified aluminum consistently. Overall resistance to wind and weather depends on the complete assembly, mounting system, and installation—not the aluminum alone.

Our metal letter assemblies are welded together for structural integrity. The attachment details are selected for the sign design and any applicable project requirements.

Sealing and Drainage

Seams are caulked to help prevent unwanted light leaks. Drain holes allow water that enters the letter enclosure to escape, helping reduce water accumulation around electrical components.

Drainage, wiring, and electrical components must be appropriate for the sign's installation conditions. Drain holes do not make a letter waterproof, and sealing should not obstruct the intended drainage paths.

Channel Letter Backplates

A backplate is a shaped panel behind the letters. It can visually unite a sign and provide a background for halo illumination. A backplate is different from a raceway, which is an enclosure used to support letters and house wiring or electrical components.

Signs Manufacturing CNC-routes backplates from solid aluminum sheet to create the intended outline.

For reverse-lit letters mounted on backplates, we add a matching vinyl letter shape behind each channel letter to help enhance reflected backlighting. We also use Signlux paints selected to improve light reflection from the painted backplate surface.

The appearance of the halo depends on the backplate finish, letter spacing, and lighting design. You can view backplate examples in our showroom or learn more about channel letter backplates.

Plan Your Channel Letter Sign

When comparing proposals, ask about return depth, back material and thickness, assembly methods, face material, lighting components, mounting details, and drainage. These details help you understand how the sign will look and how it will be built.

To discuss a channel letter sign for your Dallas–Fort Worth business, request a quote from Signs Manufacturing or call (214) 339-2227.