expansion bit
Học thuậtThân thiện
Definition
Noun: A type of drill bit with a cutting blade that can be adjusted to create holes of different diameters. It is designed to expand to a larger size than its starting diameter.
Usage
An expansion bit is a tool used primarily in woodworking. It is inserted into a brace (a hand-powered drill) and adjusted to bore holes of varying widths. The key characteristic is its adjustable cutter.
Examples
- Noun:
- The carpenter selected an expansion bit to bore the large hole for the door knob.
- For a clean, adjustable hole in wood, an expansion bit is more versatile than a set of fixed-size bits.
Advanced Usage
- Historical/Traditional Use: Expansion bits were essential tools before the common availability of power drills and comprehensive bit sets, often used with hand braces for furniture and cabinet making.
- Technical Operation: The bit has a sliding, lockable cutter that moves along a central shaft. A setscrew is tightened to secure the cutter at the desired radius, determining the hole's final diameter.
Variants and Related Words
- Expansive bit: An alternative name for the same tool.
- Adjustable bit: A broader category that includes expansion bits and other bits with variable sizing.
- Brace bit: A bit designed to be used with a brace (hand drill); many expansion bits are a type of brace bit.
- Forstner bit: A different type of bit that creates very clean, flat-bottomed holes but is not adjustable like an expansion bit.
- Spade bit: A flat, paddle-shaped bit for quick boring; it is not adjustable.
Synonyms
- Adjustable drill bit
- Expansive bit
Antonyms
- Fixed-size bit
- Solid bit
Noun
- a bit with a cutting blade that can be adjusted to different sizes