By Steve Rajeff

No matter how many different rods a company makes, there is always someone that wants a new model. One that is just a little more powerful, lighter, faster, longer, shorter, more sensitive, stronger, or has new guides, a new color, a longer handle, a shorter handle, or a different reel seat. These are a few reasons new models are developed and following are the steps to design and manufacture of a new graphite rod.

Material Selection
There are numerous grades of graphite from which to choose. Graphite is made of extremely fine diameter carbon fibers, thinner than a human hair. It offers a number of advantages, but two primary characteristics are critical in designing a rod blank - stiffness and strength. (Also known as modulus and strain rate.) Standard modulus graphite is five times stiffer than fiberglass, with a tensile strength available up to twice as strong. Some grades of graphite are up to 15 times stiffer, but actually have lower strain-rates.
One of the primary advantages of using stiffer graphite fibers is the ability to duplicate the action and power of a lower-modulus rod using less material, giving us a much lighter rod and a noticeable increase in casting performance and sensitivity. There in lies the main challenge of the designer. . . creating a design that takes advantage of the material properties and yields a rod which is "strong enough" with a high degree of both toughness and durability.
Our graphite is a flat laminate, with millions of these graphite fibers spread out longitudinally into a long, narrow sheet, pre-impregnated with epoxy resin. The weight and thickness of the sheet is determined by how many graphite fibers are used, combined with how much epoxy and "scrim" fibers are added. Scrim is a thin layer of either graphite or fiberglass (less than 10 percent of the weight of the longitudinal fibers) that provides "hoop" strength to the blank. When a rod bends, the fibers on top of the blank have to travel farther than the fibers at the bottom, so they try to get closer to each other, creating an oval effect. If the side walls don't support the structural integrity of the blank, it will collapse.
The scrim helps to keep the tube round and stops the blank from collapsing. Without the scrim, the blank wall would need to be much thicker, which in turn would make it heavier, significantly reducing sensitivity. In recent years, there have been many improvements in epoxy resins, and tensile strength of the graphite fibers.

Blank Design and Manufacture
To achieve the required rod action, (taper and stiffness), the designer selects a mandrel having a taper suitable for the application. The mandrel is a polished steel shaft that actually is the "mold" of a rod blank. The material is wrapped around the mandrel, creating the basic rod blank shape you see in the finished product. It has a fine diameter tip, with a larger diameter butt end and basically determines the flex pattern of the rod.
There can be several different rates of taper along the length of the mandrel, also determined by the designer. Next, a triangular, pennant-shaped pattern is cut out of the graphite sheet that is wrapped around the mandrel.
This pattern is calculated so there are from three to five layers of material at the tip of the blank, and from six to eight layers at the butt, creating a spiral increase of wall thickness from tip to butt. This "taper" in wall thickness adds both strength and stiffness to the blank, creating the flex or action of each particular rod. Small adjustments to the graphite pattern or mandrel taper make an amazingly noticeable difference in rod actions.
This is how the rod designer puts "personality" into each model. After the pattern is cut, the edge is affixed to the mandrel. A special machine rolls the material around the mandrel under great pressure. Next, an exterior layer of cellophane tape is also wrapped around the graphite, creating the external mold. The blank is then placed in a heating oven to cure the epoxy resin. After curing, the mandrel is extracted, leaving a hollow blank. The cellophane tape is removed and a functional fishing shaft is born.
During the bake process, the resin system actually becomes molten and because of the pressure of the cello tape, excess resin is forced to the surface of the blank. It forms spiral ridges around the blank from tip to butt, which are removed by a special micro-polish process, reducing weight and improving sensitivity and response when casting. If a special color is necessary, the blank is either clipped or squeegee coated with the appropriate hue. It is trimmed to length, and is ready for rod assembly.
In the case of multi-piece rods, each blank section follows these same steps. Specially designed ferrule reinforcement tabs and along with taper adjustments to the blank help duplicate the one piece action.

Rod Assembly
There are many more options to be considered in the rod assembly process. Grade and style of the guides, sizes and spacing; whether to use cork or synthetic grip; the grade of cork, the shape and length of the handles; the style and size of each reel seal, just to name a few. In keeping with a family of rods already in service, many of these decisions have already been made. To achieve more sensitivity, we consider lighter weight guides, or the number of guides. Another dimension is the guide ring size, or new space-age frame materials like titanium, which can enhance the feel of a rod. For greater distance, slightly larger guides and tip-top will help. For increased strength, more guides can help. For the proper balance aesthetically and physically, these are some of the important characteristics to be evaluated in the process.

Testing
It s a tough job, but someone has to do it. Actually, a lot of testing is done in the factory before field testing. Flex tests are done by hanging various weights off the tip to observe the deflection of each blank. These flex patterns are compared to other rods to get an accurate picture of the actions. Rod weights and diameters are noted.
Finally, before a rod can be released for field testing, break tests are conducted to determine "flex to failure" ratios. Many blanks and a few rods are actually cycled through a break testing machine that impart load at various angles to evaluate each rod's actual strength. Standards, as determined by the factory, must be met before they are ready for the field evaluations.
Finally, field testers and pro staffers are sent rod samples for evaluation. Criteria for testing includes actions, sensitivity, componentry, durability and subjective components. If any changes are required the entire process is repeated.

The finished product
When all the criteria for the completed rod or series of rods have been met, and the field test results compiled and approved, the rods are ready for production. Sales projections are computed by the sales team, inventory levels are determined and production schedules are set.
The entire process can take as little as 45 days, but normally takes about six to ten months. This gives us time to determine a sales strategy, which includes sales samples, inventory, promotions, advertising and media communications.
The faster a company can react to the consumer demand, the more successful it becomes. The challenge is to create exactly what the end-user wants and enough interest in the new product to maintain sufficient levels of sales to keep the manufacturing process efficient and profitable.