In fact, these days when describing reels, "materials" refers to aluminum far more than all other metals combined. It's almost universally used in reels designed for saltwater applications, inside and out. Frames and spools in particular are aluminum.
Why? The metal has all the essential attributes, says Paul R. Howell, Ph.D., a professor of metallurgy at Penn State. "It's lightweight, resists corrosion and is relatively strong."
While strictly designed for freshwater use, Daiwa's featherlight magnesium Steez reels have been treated for corrosion resistance. Below: Highest quality reels are, like this Alutecnos, nearly all machined from aircraft-grade aluminum.
Aluminum alloys are designated by numbers that reflect their makeup. Most better reels use aluminum in the 6000 series, commonly "6061 T-6 bar stock." Manufacturers often refer to this proudly as "aircraft grade." Alutecnos uses a 6082 stock, says Eros Cattaneo of Alutecnos USA in Miami. This reportedly offers even more corrosion resistance and heat dispersal (and is used in engine components in cars made by Ferrari and Porsche). But many high-end reel manufacturers swear by 6061 as optimal, such as David Nilsen of Accurate, who says, "It's readily available, best for machining and has great corrosion protection after anodizing."
? Bar Stock - A high grade of aluminum machined from bars into specific parts and pieces, such as reel frames. Generally better reels use bar stock, though grades of the stock may vary.
? Aircraft Grade - This accurately reflects the quality of aluminum demanded by aerospace applications, and typically will refer to bar-stock aluminum in the 6000 series.
? Anodized - Aluminum forms a natural barrier to corrosion because its surface oxides to leave a thin, hard, dark-gray protective coating. If scratched to the bare surface, it "heals" by reoxidizing. Anodizing basically makes this coating thicker to further improve corrosion resistance and can, at the same time, add lustrous colors. Nearly all reels, especially designed for salt, undergo anodization for both protection and cosmetics. (Zebco claims to take that one step further with a proprietary "saltguard" finish that represents "more than 100 separate processes," according to Chris Littau, engineering manufacturer for Quantum, Fin-Nor and Van Staal reels.)
Chances are if a reel's hype makes no mention of any of the terms above, it's a different grade of aluminum alloy. That does not mean it's inherently weak or not durable. It probably does mean the reel's made by forging or die-casting or both, and not machined. In fact, the bar stock that works so well for machining reels would not be a good choice for forging or die-casting.
? Forged - Rather than cut aluminum into the desired shape as does machining, forging basically involves pounding heated metal into shape. Parts in many reels are made this way, but are often cold forged. This involves working the aluminum at room temperature but under great pressure. Cold forging is considered stronger than hot forging. Forging can actually strengthen aluminum by refining the grain orientation. (Aluminum has an inherent "grain" as you'd see in a 2x4.) Often the specification of a part as "forged" is designed to distinguish it from (as a step above) die-cast.
? Die-Cast - True to its name, the third of the three common processes for shaping aluminum into fishing reels calls for injecting heated metal under high pressure into a permanent mold. Once a part is molded, die-casting can pump out exact replicas like a photocopier prints pages, making it quite cost-effective. All parts should be identical and come out with a good surface finish. A great many reels rely on die-cast parts without problem, especially where severe demands of heavy braid aren't such a factor; you wouldn't expect to find many die-cast components in pricier reels. Also important is how and how much die-cast parts are finished. That is, die-cast parts generally still require at least some machining to create a better fit.
? Stamped - This simply indicates a form of mass-producing parts from sheet aluminum, essentially cutting them out like cookies. That's a pretty good simile for relatively flat side plates, prevalent on many conventional reels. Like die-casting, it's quick and easy and produces a product acceptable for many uses. But those anglers demanding rugged performance from their reels should keep in mind that machined or forged side plates will be stronger. (Also some conventional reels use graphite side plates, sometimes covered by a veneer of aluminum. These models offer more affordability but less strength and rigidity.)