The Complete Handbook of Chainsaw Chains

Chapter 1: Understanding Chainsaw Chains

Before you think about the engine, the bar, or the brand name on the case, you should think about the chain. The chain is the only part of the chainsaw that actually does the job you paid for. It's a high-speed cutting tool that works itself to death in extreme conditions. The motor just spins it; the bar just holds it in line; the chain is what converts the machine's power into a clean cut. If you treat the chain as an interchangeable accessory you buy at the last minute, you're setting yourself up for slower work, firewood that's nothing but sawdust, and potentially dangerous kickback.

To understand a chainsaw chain, you need to abandon the idea of it as a single loop of metal. It's a precise array of small cutting teeth, each one individually shaped to slice a tiny sliver of wood. The chain is driven around a grooved bar, with the cutting teeth facing outward. As the chain travels at high speed, each tooth takes a bite, and the waste material, in the form of sawdust and chips, is carried out of the cut through the groove in the bar. The cut you make is the cumulative result of a series of micro-cuts, each one slicing a piece of wood that is too small to see individually, but together they produce a kerf that is wider than the bar itself.

Let's break down the chain's anatomy, because each part has a job.