Roughing Taps
Straight fluted taps made undersize to reduce the load on the finishing tap and particularly for difficult tapping operations.
Recommended for use when tapping steels or when close tolerance fits are required, reducing wear on the finishing tap.

Finishing Taps
Hand or machine tapping for through holes and blind holes where ample chip clearance is available.
The lead chamfer permits easier starting and requires less tapping torgue than bottoming taps.

Bottoming Taps
Used for tapping blind holes when maximum full form threads are required in minimum depth holes.

Spiral Flute Taps
Tap designed with spiral flutes in the same "hand" as the thread. This directs the swarf backwards out of the hole. Recommended for blind or deep hole applications in soft (e.g. aluminium) materials.
Die to the suitability to blind hole tapping the lead chamfer is normally that of a bottoming tap.

Spiral Point Taps
Designed primarily as a machine tap for tapping through holes.
The spiral point is formed in the lead teeth at an angle to the tap axis. The swarf, due to the cutting action is pushed forwards ahead of the tap.
The flutes of the sprial point tap serve only to deliver lubricant to the cutting edges, therefore much shallower flutes are used.
Subsequently the tap has greater strength and makes precise tapping possible.
Not recommended on abrasive materials.

ArmaCoil Gauges
Gauges are available in both 5H or 6H class of fits for metric threads, 2B or 3B for Unified Threads and close or medium for Whitworth Threads.
Class of Fit of the finished assembly is dependant on the accuracy of the tapped hole. If the tapped hole gauges correctly it is not necessary to gauge the installed insert. After the ArmaCoil is installed, the Go Gauge occasionally does not enter freely. However the insert will always seat itself when the bolt or screw is installed and tightened.