Seco introduces Threadmaster TM and DTM thread milling cutters
2 mins read
Seco Tools (UK) has introduced the Threadmaster range of solid thread milling cutters designed to produce high precision threads on what are often high cost components. As one tool can be used to mill several thread sizes, it also helps manufacturers to reduce tool inventory costs.
Threading is usually one of the last machining operations to be performed on a component. As such there is often a lot of value already tied up in the component. It is therefore critical that such operations occur smoothly avoiding expensive scrapping and/or re-working of parts.
The TM thread milling range makes threads within narrow tolerances and without burrs. The tools provide a more reliable way of milling threads than taps which can get broken. Thread milling is also more suitable for machine tools with direct drive spindles where rotational speed can be over and above 12,000 rpm. In these conditions it is difficult, or even impossible, to get the combinations of low speed and high torque necessary for tap threading.
To produce the thread profile the thread mill cutter is inserted into the hole along the axis of the spindle, deep enough to produce the full thread depth required. The control moves the thread mill out to the hole diameter until the threads cut into the sidewalls of the hole. The thread mill then moves in a 360° circular motion until it is back to it starting position.
During this circular motion the thread mill must be lifted towards the top of the hole or moved along the Z-axis of the machine one thread pitch or lead to produce a thread. This lifting movement in conjunction with the circular motion is called helical interpolation. For tapered threads the mark in the thread profile when the machine shifts rotational direction can be avoided.
Machines must have a helical interpolation program capability to utilise a thread mill. After the 360° rotation, the tool returns to the centre of the hole and is extracted from the part.
The TM range of solid thread milling cutters is suitable for a number of applications and materials, including hardened materials, cast iron, steels and aluminium alloys. It covers dimensions from M1 x 0.25 up to M20 x 2.5 and has cutters for UN/C, W and NPT/F threads.
Seco has introduced its Threading Wizard software to simplify the selection of tools and cutting parameters. This software helps the correct identification and selection of the most appropriate holder and insert, identifies the best operating parameters and then downloads this information to the machine CNC.
For machining operations where the focus is on productivity rather than precision, Seco has also introduced its Drilling Threadmaster (DTM) range. Drilling, chamfering and milling a threaded hole are achieved in a single operation.
The tip of a DTM tool drills a hole where no extra depth is required for threading, and as it reaches the bottom, chamfers the hole automatically. The threads are then milled via helical interpolation and the DTM is retracted.
Instead of three tools – drill, chamfering tool and tap – only one is required with consequent reductions in cycle times.
Both TM and DTM tools are based on the Max D-concept which creates a large, strong core that prevents bending.
The TM range is suitable for up to size M16 in all types of modern machines with helical interpolation capability. For larger sizes the spindle must be at least ISO 50 or HSK 63 or equivalent to get a successful result using the full cutting depth.
