What is the diameter of older magnets vs. the newer Alnico rods?
Many of the early magnets used on Fender instruments had a rough surface sand cast magnet with an average diameter of .197 . The larger diameter magnets were used from early to late 50 s. The standard size became .187 in diameter. The early magnets were raw with rough sand casting pits. The outer surface had a darker color and brighter when surface ground. The magnets fit quite tight into the early vulcanized fibre flatwork and many pickup have amazing longevity even with all the years of use and abuse.
