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The difference between the two types of points is in the design of the outlining spurs. The Brad Point Drills that work best in softwood have rounded spurs, which help to hold the grains of the wood down while sheering them off. There is a certain amount of rubbing that occurs between the outlining spur and the wood before it is cut. The outlining spurs on Brad Point Drills for hardwood come to a sharp point and simply cut the stronger grains off clean. No rubbing occurs and therefore no unnecessary heat is produced by the cutting action.
Another feature of the Brad Point Drill that could affect its cutting ability is the actual brad or pyramid point in the center. Although the sole purpose of the brad is to guide the drill through the material and keep it running straight, the shape of the brad can affect the results. The brad itself does not actually cut the wood. It mainly scrapes and pushes the wood aside. If the base of the brad is too thick or fat, the drill will be much harder to push especially in hardwoods. A brad that is too thin will allow the drill to cut freely but may break off in the process. It is also very important that the brad is exactly centered at the point of the drill. An off center brad can cause a drill to cut larger than it actually measures.
We often vary the length of the brad to achieve different results. A longer brad can be used when a hole needs to be drilled on an angle instead of straight into the wood. Drilling as much as 45 degrees or even 60 degrees from vertical is possible by extending the length of the brad. A shorter than normal brad may be required in the case of a hole that needs to be drilled close to but not through the back of the material.
Brad Point Drills also work well in most plastics, nylon, fiber, fiberglass and many other man made materials. If you have a question about Brad Point Drills, just call and ask a Fuller.
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