A friend of mine called me this morning with a machining question and I don't know how to answer his question.

He needs to make a socket (a round bottom hole) in a steel plate that a 1" dia steel ball bearing will set into. The circumference of the top of this socket has to be .842 (+/- .005).

Does anyone know how to figure out how deep to make this socket so that the dia at the top of the socket is at the required circumference? I don't have a clue how to figure this out, math never having been my strong point...

The only way I would approach something like this is by trial and error, and even then I'm not sure how I would measure the circumference of the top of the hole accurately enough for what he needs.

Any help would be appreciated. Thanks in advance

He needs to make a socket (a round bottom hole) in a steel plate that a 1" dia steel ball bearing will set into. The circumference of the top of this socket has to be .842 (+/- .005).

Does anyone know how to figure out how deep to make this socket so that the dia at the top of the socket is at the required circumference? I don't have a clue how to figure this out, math never having been my strong point...

The only way I would approach something like this is by trial and error, and even then I'm not sure how I would measure the circumference of the top of the hole accurately enough for what he needs.

Any help would be appreciated. Thanks in advance

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