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heyOldMisterCrow; Perhaps your not analyzing the situation enough. In Ron's example the wire, whether it be aluminum or copper is resisting the bending force of the branch by flexing up to it's elastic limit at which time it "bends" or undergoes plastic deformation. Because the wire in this test is acting like a cantilever, the amount sticking out beyond the fingers is important because the stress causing the wire to bend is proportional to the square of the length ( so that a wire sticking out 2 inches is subjected to twice the stress as a wire sticking out 1.41 inches and how many people can estimate either of those two lengths accurately). Secondly, a wire half the diameter of the branch has a moment of inertia ~2.25 that of a wire 1/3 the branch diameter (a function of the square of their diameters) which means the larger wire in this case has ~ 2.25 times the holding power for bending the branch. Ergo, and hertofore, the best solution as I see it is to use aluminum wire about 1/3 the diameter of the branch to be bent based on the diameter of the branch in the middle of it's length. This wire runs nearly the entire length of the branch and subsequently is a little undersized where the branch meets the trunk and maybe a little oversized out near the end. If the branch needs to be bent near the trunk a second wire is installed that runs parallel with the first but only ~ halfway down the branch. In actuality I haven't looked at my engineering books on this subject in 30 years and I probably have everything a$$-Backwards, BUT, it works for me and I like aluminum wire better.

31-Jul-2004	#6
heymikey(deceased) bonsaiTALK Master Join Date: Oct-2002 Location: East bay, Ca. Country: USA USDA Zone: 9 AHS Heat Zone: 7 Posts: 400	heyOldMisterCrow; Perhaps your not analyzing the situation enough. In Ron's example the wire, whether it be aluminum or copper is resisting the bending force of the branch by flexing up to it's elastic limit at which time it "bends" or undergoes plastic deformation. Because the wire in this test is acting like a cantilever, the amount sticking out beyond the fingers is important because the stress causing the wire to bend is proportional to the square of the length ( so that a wire sticking out 2 inches is subjected to twice the stress as a wire sticking out 1.41 inches and how many people can estimate either of those two lengths accurately). Secondly, a wire half the diameter of the branch has a moment of inertia ~2.25 that of a wire 1/3 the branch diameter (a function of the square of their diameters) which means the larger wire in this case has ~ 2.25 times the holding power for bending the branch. Ergo, and hertofore, the best solution as I see it is to use aluminum wire about 1/3 the diameter of the branch to be bent based on the diameter of the branch in the middle of it's length. This wire runs nearly the entire length of the branch and subsequently is a little undersized where the branch meets the trunk and maybe a little oversized out near the end. If the branch needs to be bent near the trunk a second wire is installed that runs parallel with the first but only ~ halfway down the branch. In actuality I haven't looked at my engineering books on this subject in 30 years and I probably have everything a$$-Backwards, BUT, it works for me and I like aluminum wire better.