Tractor Digger What size auger for setting the 4×4 posts.? I am ordering a post hole digger for my tractor to be used Kubota L3400 in the setting of 4×4 (actually 3.5×3.5) posts for the fence. Should I ask for a bit of 4 or 6 inches. 3.5 x 1.4 factor for the diagonal given [...]