This was a small stump, which I could have just pulled with a chain, but you get the idea. You can see in the background the fence area I've been clearing. Notice that the cross-bar on this lever (the place where the chain connecting the lever to the stump is attached) is located fairly close to the top of the lever. This allows me to exert force over a larger distance at the loss of mechanical advantage. However, this is not of too much concern since I know that the truck can already exert more force than the steel tubes can withstand. If, however, I were to construct a new lever from stronger materials, it would be preferable to place the cross bar closer to the fulcrum of the lever. |