A pointed iron bar for loosening patterns from moulds, which is inserted vertically into a hole in the pattern and caused to vibrate by being struck with a hammer.
Origin
Late 19th century; earliest use found in Lockwood's Dictionary of Mechanical Engineering.
Definition of rapping bar in US English:
rapping bar
noun
Founding
A pointed iron bar for loosening patterns from moulds, which is inserted vertically into a hole in the pattern and caused to vibrate by being struck with a hammer.
Origin
Late 19th century; earliest use found in Lockwood's Dictionary of Mechanical Engineering.