Chainsaw chains undergo enormous pressure from the force and speed of the cutting. Chains, while made of steel, can damage quickly from these forces, and replacement chains can get expensive if you wear them out too fast. Chainsaw chains can be repaired and fixed with a few inexpensive tools. However, these tools are intended for experienced users only as damage to a chain can cause serious injury and even death.
All chainsaw chains will dull under the force of cutting through wood. The teeth need to bite out the wood, and, like a razor, will dull over time. Teeth can dull even quicker if the running chain hits the ground, duff, rocks or hidden metal. A round, short hand file can be used to grind off the damaged areas of the tooth, restoring the cutting angles. These round files must match the pitch of the chain — the distance between three rivets divided by two. Round files wear out quickly, so purchase them in bulk to save on costs.
The depth gauges, the metal posts in front of the cutters, can also get damaged during cutting. Like the teeth, these metal posts need to be filed down regularly during the chain’s life. Use a crosscut flat file to grind the depth gauges down so they are even with the teeth again. Filing the depth gauges can be a little tricky for the inexperienced, so use a depth gauge guide to ensure you don’t take too much off the gauges. When too much is taken off the gauges, the chain will have more of that “bite,” which tends to pull the sawyer into the wood as the chain engages the wood.
Teeth can get bent, chipped beyond repair or broken off completely, usually rendering the chain worthless. However, a chain breaker can break the link of a chain off so that a new link can be put on the chain. This tooth will need to be filed into the same length as the rest of the cutters, however. The chain breaker will also come in handy if you need to lengthen or shorten the chain for different bar sizes. Chain breakers come in bench-mount and pocket-size models. Don’t use anything besides a chain breaker to break apart a chainsaw chain.
Once the new link is added to the broken chain, a rivet spinner will put a new rivet into the link. The rivets, or tie straps, hold all of the links together. These rivets take most of the pressure of cutting, so they must be properly secured for the chain to work. For this reason, don’t use anything besides a rivet spinner to put new rivets into a chainsaw chain. Most rivet spinners come in a bench-mount model that uses a spinning handle to press the new rivet into the drive link.