Auger blades are the cutting devices at the bottom of an auger. The blade attaches to the auger and provides a sharp biting edge in which to begin the auger's cut. Some auger blades are serrated to help bite into very hard surfaces, while others are smooth and can be used for softer surfaces. The blades are replaceable and in most cases they are able to be resharpened. This allows for a properly maintained auger that is always ready to perform at its best.
There are many types of augers and many different uses for them. In the case of an earth digging auger such as the type used to dig fencepost holes, dull serrated auger blades are used. The teeth on the serrated blades aid in loosening rocks that might otherwise hinder the auger's digging potential. The large serrations act like fingers to work the rocks and stones loose.
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Ice augers are used by many fishermen to drill holes into the frozen surface of a river or lake. These auger blades are typically smooth and razor sharp. This allows the auger blades to shave away the ice and bore through to the water below. Unlike earth-boring auger blades that are not razor sharp, the ice auger is designed to cut through the ice without encountering any hard objects such as rocks.
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Some augers are designed to move grain from a bin to a trailer. These auger blades are typically soft and flexible. Soft rubber blades are attached to the auger to flex and sweep the grain as the auger transports it up and out of the bin. The soft blades prevent the auger from grinding the grain into a powder. They also allow the auger to operate in close proximity to the bin walls without fear of cutting through them.
Auger blades that are used in soft ground are typically concave and act as a type of scoop to keep the auger digging down. The scoop-like blades pull the auger down while the soft ground is carried up and away by the twist of the auger. This scooped design works so well that many of the soft earth augers are required to be operated by two operators. The power of the two operators offset the pull of the auger and prevent the augers motor and controls from spinning a single operator around. Removable blades allow a single auger to be used in many different conditions.