Template:Countersink Bits Buyers Guide
From DT Online
Centre Drills (aka Slocombe Drills) were designed to provide a location for a Tailstock Centre (hence their 60deg point angle) but are commonly used to make a small starting indentation to guide further drilling in a Lathe.
- If used only to start a drilled hole then one or two of the mid-range sizes will suffice since it is only the tip of the Centre Drill that will be used.
- Choose only those made from good quality High Speed Steel and offer them carefully up to the workpiece whilst it is rotating since the smaller sizes in particular, can break easily.
 
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| Slocombe Centre Drill
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- For most non-critical work in Design and Technology, countersinking can be achieved using a Twist Drill twice the diameter of the hole in question.
- For more precise work, purpose made Countersink Bits are available.
- Choose High Speed Steel' if countersinking steel since ordinary Carbon Steel is suitable only for wood and plastics.
