TOTEM – Dies – HSS & Carbon Steel Round & Hexagonal Dies

Technical Details
Dos and don’ts – threading with dies

• Chamfer: Make a chamfer at the end of the bar at an angle of 45 degrees to remove sudden loading of the leading edges. This has to be done before starting the die-or-die nut. Also, it has to be made certain that the die or die nut is presented to the bolt squarely.

• Tolerance: The major diameter of the bolt usually has large tolerances. Use this to your advantage by reducing the diameter of the bar. Thus, the cutting force will be reduced to a minimum. If tolerance class is not specified, consider tolerance applicable for medium range i.e. 6H and 6G.

• Swarf: To direct the swarf away from the cutting area, it is always preferable to use the gun nose type of die.

• Lubricant: The cutting area should always be supplied with a steady flow of the correct lubricant.

• Split dies: To avoid rubbing, the adjustable split die should not open out. Move the adjustable screws equally by say, 0.15 mm to close the split die. If it is done unequally, there may be pressure on one side which may lead to breakage.

• Cleaning: As a norm, die nuts are used for cleaning out existing threads. Usually, the process is done by hand. Avoid using die nuts for thread cutting unless it is an exception.

• Rake Angle: Large rake angle for long chip formation whereas a small rake angle for short chip formation. It’s applicable and or workpiece material isn’t specified, assume it has intermediate tensile strength.