Persian drill

A Persian drill is a drill which is turned by pushing a nut back and forth along a spirally grooved drill holder.[1] It was formerly used for delicate operations such as jewellery making and dentistry.[2] A ratcheting screwdriver with a 'spiral ratchet' mechanism may be used as a Persian drill.

References

  1. ↑ Brown, Henry T. (1868). Five hundred and seven mechanical movements. Brown & Seward. p. 33. OCLC 6821027.
  2. ↑ Nagyszalanczy, Sandor (2000). The Art of Fine Tools. Taunton Press. p. 84. ISBN 978-1-56158-361-4.