Chain Tensioning: The chain should not sag below the bar, but it shouldn't be overly rigid either. You should be able to pull the chain down slightly to expose 1 to 3 drive teeth cleanly.Manual Lubrication: Most 6-inch mini saws feature a small internal oil tank with a transparent window. Press the rubber priming button every 10 minutes of cutting to coat the bar guide with chain oil to prevent friction burn