Though rods built of greenheart continued to be manufactured – the legendary British manufacturer, the House of Hardy, continued to build greenheart poles until the mid 1970s – split cane continued to be the material of choice for fly rods through the early part of the 20th century.
The idea that glass fibres might be spun into a new, miraculous material was first run up the flag pole in the early years of the 20th century, but it was not until forty years later that a military researcher by the name of Howland unknowingly took the first step in a revolutionary process that changed the way that the vast majority of fly rods would be manufactured.
After breaking a section of his favourite bamboo rod, it occurred to Dr. Howland that a fibreglass tube, an item that existed in abundance at that time thanks to its usefulness in industrial settings, might be the ideal thing to repair his injured rod. Howland’s glass fibre Band-Aid must have worked well, for in no time at all word had spread on the angler telegraph to a rod company in Kalamazoo Michigan operated by William Shakespeare, known to his friends as Bill.
After consulting chemists and engineers, Bill, whose company had been manufacturing and marketing fishing tackle for a long time, assembled an assembly line and began making rods of glass fibre. Applying the aptly named “Howland Process,” the employees at Shakespeare wound fibreglass yarn that had been saturated with resin on a steel rod, or mandrel, in a spiral.
This done, they wound on more glass fibre, this time aligned with the axis of the mandrel. With the second stage complete, the workers then wrapped cellophane tape so as to hold the fibres in place as the resin cured. When the fibres had cured the cello tape and the mandrel were removed to reveal a finished blank that was then built into a finished rod.
Bamboo and greenheart were manufactured to be strong by Ma Nature using her unpatented evolutionary process. Glass fibre rods were no stronger but they were a lighter. They also had the economic advantage of being relatively easy to produce in large numbers at lower cost by less skilled workers.
By the 1970s, the manufacture of fibreglass had been perfected. Sand and limestone were mixed with ingredients like sodium carbonate, and various oxides, which were then added to waste glass of similar constituency then the mixture was melted in a furnace to form molten glass.
The molten glass was then forced through a steel device containing many small holes, named spinnerets after the part of a spider’s anatomy through which the material the creature spins its web is exuded. The fibres from the spinnerets are cooled and spun into yarn, which is then woven into sheets.
Carbon fibre, a material that came into prominence during the space race, is lighter and stronger than glass fibre. It’s derived from synthetic fibres called polymers that are made of long molecular chains containing numerous carbon atoms. Carbon fibre can be made from cellulose, a polymer occurring in plants, or it can be made from an artificial polymer consisting of acrylonitrile molecules that is obtained from petroleum.
The synthetic fibre is heated, forcing out atoms other than carbon, resulting in long chains of carbon atoms. The carbon fibre is then spun into yarn, which is woven into sheets.
The carbon fibre sheet is dipped into a solution of liquid plastic resin, then squeezed between metal rollers to leave a controlled amount of resin in the sheet. The sheet is then heated to remove excess solvent and to partially harden the resin until it is slightly sticky.
Next, a metal template is laid on top of a stack of sheets. A sharp blade cuts around the template, producing several cut sheets of the same shape. One edge of the cut sheet is heated in order to attach it to a tapered mandrel. The mandrel is rolled between two heated metal rollers, known as platens, that apply pressure as layers of fibre are wrapped around the mandrel. A thin film of a synthetic polymer, such as cellophane or polyester, is wrapped around the layers of fibre.
The wrapped mandrel is then heated in an oven. The heat causes the polymer film to shrink, applying pressure to the fibre as the resin hardens. Now the mandrel is removed from the hardened fibre by using a pressurised ram to force it through a die. The polymer film is removed using a wire brush, a tumbler, high-pressure steam, splitting, or stripping.
The blank is lightly sanded to remove excess resin and to provide a smooth surface. It is then coated with layers of various protective materials. The blank is buffed between each coating to give it a smooth finish.
…to be continued…