Magnets can be machined. However, hard magnet materials – as opposed to the flexible or rubber type magnet materials – are extremely difficult to machine. Magnets should be machined using diamond tools or soft grinding wheels, and in the unmagnetized state as far as possible. In general, it is best not to try to machine hard magnet materials unless you are familiar with these specialized machining techniques.
The factors which determine cost to machine magnets are:
Quantity – the larger the quantity, the lower the cost since set-up charges must be amortized over the quantity, and special tooling can be created to machine larger quantities;
Material – SmCo magnet materials are more costly to machine since they are very brittle, flexible materials are very inexpensive to machine because of their physical characteristics;
Shape – complex shapes are more expensive than simple shapes; and,
Tolerances – the closer the required tolerances, the more expensive it will be to machine the magnets.

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