About HeliCoil Taps
HeliCoil taps are also referred to as Screw Thread Insert (STI) Taps and must be used for HeliCoil repairs. They are supplied with HeliCoil Thread Repair Kits and may be used with the same tap handles as conventional taps.
HeliCoil STI Taps are manufactured in high speed steel to the most rigid specifications. They produce holes for Tolerance Classes 4H5H and 5H for use in the general range of aluminums, magnesiums, mild steels, free machining stainless steels, and other free machining materials.
Straight fluted taps used for difficult tapping operations where it is desirable to reduce the load on the HeliCoil Finishing Tap.
HeliCoil Finishing Taps have 4 thread chamfers and are used in through holes and blind holes that allow for ample chip clearance. They are easier to start and require less tapping torque than HeliCoil Bottoming Taps.
HeliCoil Bottoming Taps have 2 thread chamfers and are used in blind holes drilled to a minimum depth that requires threads to be close to the bottom of the hole.
Spiral Flute Tap (Machine Tap)
HeliCoil Spiral Flute Taps have a 2 thread chamfer as well as spiral flutes and they are specially designed for efficient removal of stringy chips out of deep or blind holes in soft materials and effective chip disposal in production tapping operations.
Spiral Point Tap (Machine Tap)
HeliCoil Spiral Point Taps incorporate an angular grind at the point end of the tap which shears chips and drives them forward of the tap. They are used widely in long thru holes and blind holes with ample chip clearance.
HeliCoil Spiral Point Taps are free cutting and provide increased tap strength. However, they are not recommended for abrasive materials.
Spark Plug Taps (Piloted Reamer Taps)
HeliCoil has specially designed spark plug taps, also known as Piloted Reamer Taps, for use in spark plug applications.
These taps have a pilot thread at the front, to pull the tap into the hole, followed by the reamer section which removes the damaged threads and then by a larger tap section which cuts the proper threads for the HeliCoil spark plug insert to be installed. No prior drilling of worn out threads is needed with HeliCoil spark plug taps.
Special HeliCoil Taps made to different limits, configurations, or to cut difficult materials, or for very high production are available upon request. The following data should be provided at the time of order:
- Thread size
- Class of fit - e.g.4H5H, 5H, special size to special tolerance
- Material to be cut, and its hardness
- Hole configuration - e.g. through or blind hole including length of drilled and tapped hole
- Tap type - e.g. roughing, finishing, bottoming, spiral point, spiral flute
- Special features e.g. length, shank diameter, chamfer length, tap material
- Special coating required