Tapping a Straight Hole
by Jim Connell
Nobody likes to break a tap and one of the main causes of broken taps is starting the tap at an angle to the drilled hole. There are tap guides available to help with this, but the method I use requires no extras.
After drilling the tap hole, remove the drill from the chuck and replace with the tap. Tighten the chuck securely (using all three holes will help). Place the chuck key in the chuck as shown and, with slight pressure on the quill feed handle, use the chuck key as a handle to turn the tap.
This method works equally as well in a mill or drill press.
Like most shop tasks, use caution and make sure the mill or drill can’t be inadvertently turned on when the chuck key is in the chuck. Also, removing a belt or putting the spindle into a neutral position will help in turning the tap and will allow a better feel of what’s going on.
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