Here’s a description of how LEER fiberglass truck caps and tonneaus are made. While the final product may look simple, it is the result of rather sophisticated engineering and manufacturing.

Precise molds are a critical ingredient
Extraordinarily accurate molds are fabricated, using computer-aided design and skilled handcraftsmanship by the LEER mold shop before being released to the production teams at the three LEER plants (in Elkhart, Indiana; Milton, Pennsylvania; and Woodland, California). While molds may last for years, they also require constant maintenance to keep their mirror-finish surfaces and dimensional accuracy. Literally hundreds of molds are maintained by LEER, and each mold is inspected, cleaned, waxed, polished, and prepped each and every time it is used.

The first element in the mold: “gelcoat”
The first thing put into the prepared mold for your cap or tonneau is a layer of “gelcoat,” a synthetic polymer designed to flow smoothly into every part of the mold, in a thin (2-3 mils) but durable layer that will form the smooth-finished outside surface of your cap or tonneau. It is the gelcoat that will be prepped for painting and will get the exterior paint finish you see.
Because it is directly under the painted surface, LEER gelcoat comes in three colors (white, light grey and dark grey), designed to provide the best coverage, based on the color of paint that will be used on the part.

The key structural component: Random-strand fiberglass
The next step adds the key structural component, random-strand fiberglass. Long, thin filaments of glass fibers are chopped to lengths averaging 1 to 2 inches long, and are combined with resin (another advanced polymer plastic) and a catalyst that enables the combined ingredients to harden and cure. This layer of chopped glass and resin is applied by skilled operators who control the thickness of the application to within a few hundredths of an inch. If the fiberglass layer is too thick, it is too heavy and too rigid; too thin and it won’t have the required strength.

Hand-rolling of the fiberglass eliminates air bubbles and voids
While the combination of glass and resin is still curing, it is meticulously rolled out, another hand operation that eliminates any air that may be trapped in the fiberglass layer. At this time, too, reinforcements of marine grade plywood and metal are added to the mold, where they will be encased in another layer of glass and resin. These reinforcements make it possible for LEER to add racks, lock hardware, hinges, storage boxes, and other bolt-on parts that would otherwise stress the fiberglass.

A lightweight but resilient reinforcement layer is added
A layer of “tri-cel” honeycomb or striated fiber is added at this time, too. When in contact with resin, this internal stiffener provides an incredibly hard, durable, and resilient layer of reinforcement that adds significant strength with minimum weight to the roof area of the cap or tonneau.

Additional fiberglass is “hand-laid” in dramatic curves and complex shapes
Also, depending upon the design, additional fiberglass is added in the form of hand-laid sheets of “woven roving.” This application further strengthens areas of the cap or tonneau that have dramatic curves and complex shapes. Each step of the way, each layer of fiberglass and resin is rolled out, just like the first, to ensure there are no air voids in the structure.

Catalyst hardens and cures the fiberglass
With the fiberglass and reinforcing work complete, caps and tonneaus are set aside so the curing process generated by the catalyst can continue. Soon after it is complete, the new caps and tonneaus are released from the molds and trimmed of excess material. The production process is far from complete, however.

Critical eyes inspect every piece; fiberglass rails are added to caps
Each fresh part is individually inspected by experienced eyes, and any surface flaws in the molded part are noted and corrected. Caps go through yet another round of fiberglass production, where the fiberglass “rails” that mount to your truck bed are molded and mated to the caps, using additional hand-applied layers of fiberglass and resin. Caps and tonneaus are mounted on individual shipping boards so they can move through the assembly process with a minimum amount of handling.

Window and door openings are carefully cut; headliners are added
Caps are moved to the cutting operation, where the openings for windows and doors are first carefully marked, then precisely routed, so they can accept any of LEER’s wide range of windows and doors. Our commercial grade marine carpet headliner option is installed at this point, too.

Painting - adding gorgeous color
Inspections continue, surfaces are refined before parts are painted in a clean, controlled environment
More inspections and further preparation are performed as caps and tonneaus are led to sophisticated paint spray booths where lighting, air pressure, humidity, temperature and filtration provide an ideal painting environment. Using automotive quality paints and OEM-matching paint formulas, highly trained painters apply a basecoat of color, then a clearcoat for UV protection and gloss. Each cap and tonneau is then sent through temperature-controlled heat tunnels, to cure and set the fresh paint.

Hardware is added, caps are water-tested
Windows, doors, locks, latches, hinges, seals, and a wide range of other hardware and accessory options are added at this point. It is here that the built-in reinforcements of metal and wood are so critical. The famous “LEER” logo is also applied at this time. All caps are water-tested too, using either a water shower booth or ultrasonic leak detection equipment.

All products pass a final approval before they can be released for shipment
Once the assembly process is complete, each and every unit leaving the “back door” of the plant is subjected to a final inspection. Shipment is scheduled only after each cap and tonneau has passed that inspection. The result of the LEER manufacturing process is a truck cap or tonneau that is everything you want it to be: light, strong, resilient, precise and beautiful!

LEER Transportation - the final step in the process
LEER operates its own fleet of tractor trucks towing custom-designed trailers from coast to coast, delivering LEER truck caps and tonneaus to the industry’s largest network of dealers. The LEER fleet includes a wide range of delivery equipment to accommodate the unique dimensions and shipping considerations of our product line.