How to perform Tapping (Thread Cutting) with a Magnetic Drilling Machine? 

wdipl Comments 0 May 9, 2017

A magnetic drilling machine performing tapping (thread cutting) on a flange.

One of the best features of a magnetic drilling machine is to perform Tapping, also called as Thread cutting. The magnetic drilling machines with reversible motors are ideally suited for thread cutting. The basic requirement for a magnetic drilling machine to perform thread cutting are, reversible motor, speed control and the most important, torque control.

  • 1.As per the size of tap to be made, select the magnetic drilling machine.
  • 2.For example, to tap M 24 the operator must drill first a 22 mm diameter hole with an annular cutter.
  • 3.Once the hole is made, remove the annular cutter from the machine.
  • 4.It is important that after making the hole the magnet of the machine should not be switched off or should not even move the machine.
  • 5.Now insert the M 24 tap in the tap adapter.
  • 6.It is very important to lubricate the tap before tapping with special cutting paste.
  • 7.After lubricating the tap, switch on the motor of the machine.
  • 8.Reduce the speed of the machine to the lowest level.
  • 9.Increase the torque of the machine to the highest level.
  • 10.Slowly give feed to the machine until the tap enters the hole
  • 11.Once the tap is inside the hole, the tap takes the travel and the operator does not have to give feed.
  • 12.Once most of the tap head is out of the hole from below, switch OFF the motor. Note, that the Tap should not come completely out of the hole, because while reversing the tap, it may damage the threads made.
  • 13.After stopping the motor, change the direction of rotation of the motor to left,
  • 14.And then start the motor again. The tap now takes the reverse feed and comes out of the hole making a perfectly finished thread.
  • 15.The advantage of tapping with magnetic drilling machine is that, it is very fast and also Saves tool cost by reducing the tool breakage.