Buggy and Cart Shafts are most often made from hickory wood. Hickory is plentiful, easily harvested, and has a fair amount of resiliency - handy when your horse bends his 1200 body against the shafts.

Ideally, the shaft tip end should be aligned with the point of the shoulder on a horse. Start with a size somewhat close to this. You can make up the difference when adjusting your harness

Buggy shafts are available in light (suitable for sleighs and light buggies, such as runabouts, etc), standard, most buggies use these, draft, thicker and longer, and pony, shorter. The crossbar is a mortised piece of wood that the shafts will fit into on each end, thereby holding them together with a little more stability. Of course you will always need shaft irons. These are attached by carriage bolts to the shaft itself. Simply drill the holes after you have placed the irons on the assembled shafts, and insert the carriage bolt (square inset, round head) with the threads of the bolt going through the wood. You should have a T plate between the wood and the head of the bolt.

Buggy Shafts are available in standard bend (most popular), EZ bend (not quite as tight of a bend in the heel), and double bend (most spring wagons use these) The "heel" of the shaft is the end of the buggy shaft closest to the buggy.