explain the various characteristics of golf shafts. Include such factors as materials, sizes, playing/bending characteristics, etc.
Too small a space to explain all that you ask. You should come to our advanced shaft technology school. In short, shafts are made of steel, lightweight steel, composite graphite, graphite with steel fiber and combinations of other materials. Any material can be designed to have a particular flex profile. However, differing materials transmit vibrations differently, so even though you might have two different materials with the same flex profile, they will not “feel” the same due to the material. The most important aspect of a shaft in determining it’s playability is the overall flex profile and it’s weight. There are other elements, such as the torsional stiffness, but they play lesser roles in the overall performance. Diameters and wall thicknesses of shafts will vary depending on the materials and the flex profile the designer is after. That’s the cliff notes version of the items you mentioned. Hope it helps.