What are the different types of brad point bit?
What are the different types of brad point bit? |
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Brad point bits are made in two different types. Some are designed for hardwood and some are designed for softwood. | |||
Why are there two different designs? |
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Hardwood grain is tough, and needs to be cut by a sharp edge. Using a blunter softwood bit can cause heat to build up as the bit forces its way through the grain. | |||
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However, softwood grain is more delicate and can sometimes be prone to tear out if too agressive a tool is used. | |||
Hardwood brad point bits |
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The spurs on hardwood brad point bits are angled down towards the wood. The spurs end in sharp points, and they contact the surface of the wood immediately after the brad, slicing through the grain neatly and efficiently while generating the minimum of friction and heat. | |||
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Hardwood bits are also used for non-wooden materials, as their sharper spurs are required for cutting through them successfully. | |||
Softwood brad point bits |
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The spurs on softwood brad point bits are much less aggressive, following the angle and contour of the lips rather than protruding too far forwards. Additionally, they are rounded off so that more of the spur can contact the wood in one go. This applies more even pressure to the sides of the hole to prevent the wood fibres from tearing. | |||
What happens if you use the wrong bit? |
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In most cases, you shouldn’t have too much of a problem using a hardwood bit on softwood, especially if you are drilling holes for dowels. | |||
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If there is a small amount of splintering around the opening of the drill hole, it should be easy to conceal when your joints are properly aligned and glued. There are also steps you can take to prevent tear out on the reverse side of the workpiece if you are drilling all the way through. For example, you can drill just far enough for the brad to emerge, before flipping it over and completing the hole from the other side.
For a step by step guide, see: |
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Using a softwood bit on hardwood can be more problematic, as you may find the grain may resist being cut by the drill bit. The resulting friction may lead to a build up of heat that could cause the bit to lose temper or the borehole to char. | |||
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Either one of these outcomes could end up costing you money. | |||
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