I need to build some camp stools in the style of the ones made popular by Chris Schwarz in his Lost Art Press book, “Campaign Furniture.” Chris recommends making the legs 1-1/4” diameter at their center where the 5/16” diameter hardware joins the legs in a pivoting arrangement. This is the weakest point in the structure, and he notes that the diameter he turned his legs is strong enough even for mahogany.
I have recently acquired clear, straight grain, 8/4 hickory stock with very minimal runout that I intend to use. Of course, I searched for the hickory because it is much stronger than mahogany, or any of the other woods Chris recommends using. The question is, how much can I reduce the diameter of the legs and still safely support a person up to 16 stone (225 lbs. or 100 kilos)?
I would like to reduce the weight as much as practical, and I would like to have as little waste as possible, as the hickory is pretty expensive and relatively dense. Getting more if I want to build more stools is also inconvenient. Therefore, I would prefer to split the stock in half so I could extract two legs from each thickness.
Note that hickory is used for hammer and axe handles, and is even stronger and more shock-resistant in these applications than ash. Air dried hickory is even stronger than kiln dried, but all I have found in the required length is kiln dried. There are several species of hickory, including bitternut, pecan, mockernut, shagbark, shellbark, pignut. Shagbark is the strongest, but the lumber yards do not break down their stock by species, so I am stuck using what is available.