Logging companies had great difficulty using saws with no power in logging forests. The birth of the lightweight, handheld gasoline-powered chainsaw changed this equation and is thus hailed as an event of both ecological and political significance. Chains must occasionally be removed from the saw to ensure that they stay sharp. This is lightly done using a round file, or, if you want to be more thorough, you may use a specialized, electrically powered sharpening jig. This helps ensure that each of the cutting faces is at the right angle and is carefully balanced to ensure the saw's efficient operation. A common mistake is reassembling the saw with the teeth facing back to front, thereby reducing its cutting power. Carbide chainsaw blades need to be sharpened by a certified chainsaw repairman since they cannot be sharpened by ordinary sharpeners. Normally, each segment in the chain (constructed from the riveted metal like a bicycle chain minus the rollers) features a small, sharp blade called a tooth. A 'skip-tooth' chain has a tooth only on every second link; this is used to minimize the risk of clogging the chain when cutting soft wood. In modern saws, the blades' teeth are not straight but rather have a forward section that chips a piece of wood from the bottom. Another section found at the right angle to the first cut chips a piece of wood from the walls of the cut. Left- and right-handed teeth are found, depending on which wall of the wood they will cut. The chain has left and right teeth alternately placed. The underside of each link contains a small metal finger that keeps the tooth centered between the bar rails. It helps to carry the lubricating oil around the bar and engages with the engine's drive sprocket inside the saw's body. The engine drives the chain around the track at a high speed, giving rise to rather rough yet effective cutting action. |
