Tapping a single hole requires one of two methods, a self-reversing tapping head or a tapping machine that automatically reverses at the required tap depth.  When tapping with a multiple spindle head a simple method to tap two holes simultaneously is to replace each collet tap holder with a self-reversing tapping head.  This enables simple machinery, such as a drill press or a vertical milling machine to tap multiple holes at one time without the need to reverse.

A tapping machine with a lead screw feed and reversing is used for Class 3 specification threads.  It feeds the tap exactly one pitch per revolution.  Its' disadvantage is that with any lead screw only one particular pitch can be tapped.  A change in the lead screw feed is required to do different pitch threads.  It is also not capable of drilling or reaming.  Our multiple spindle heads can be attached directly to this style machine since all our spindles rotate in the same direction and are geared at a 1:1 ratio.

Drilling machinery with reversing capabilities can use our multi-spindle heads to tap.  The depth at which the spindles reverse must be capable of being set with a sensor or be timed by the operator.  If timing by the operator is required a reasonable skill level is necessary.  These machines can tap any pitch within their speed and feed capabilities.  Automatic feed is not used.  The feed is set by the motion of the operator.

AutoDrill offers a versitile method to tap multiple hole simultaneously without the high cost and maintenance of lead screw tapper.  We mate multiple self-reversing tapping heads to the multi-spindle head to convert any drilling machine into a multi-hole tapping setup.  The tapping heads have the added advantage of incorporating both start and feed cushions to the spindle.  These features reduce tap breakage and allow a clean start to the threads.  These heads can also re-engage into existing tapped holes to either clean the thread or for thread inspection.  Any thread pitch can be made with the setup.