Calculate My Cycle Time

RCT50

How to calculate the cycle time for tapping with a self-reversing tapping head.

If you are currently tapping using a synchronized or rigid tapping cycle, it is not possible to calculate your cycle time because the machine spindle has to slow down, stop, reverse, and re-accelerate twice for each hole. It does not matter what RPM you program because in reality the machine spindle can't maintain a constant speed during the tapping cycle.

With a self-reversing tapping head the machine spindle turns continuously in the forward rotation direction at the programmed speed. The machine simply has to feed in and out of the hole and the tapping head makes the reversal almost instantly when the machine retracts. This means it is possible to calculate an accurate cycle time using the tapping head. To make a comparison between rigid tapping and using a tapping head you will need to time the actual cycle for rigid tapping and compare this to the calculation below for the tapping head.

The below calculations are based on our reduced cycle time programming which is a simple subprogram that can be called up for each hole location. For more information please see our complete Instructions on programming.

Tapping Speed Chart
Please note the values below are for reference only. We recommend consulting the tap manufacturer for a recommendation for your particular tap. For the best results and longest life of the tapping head's drive parts, select a conservative spindle speed, and be sure not to exceed the maximum speed limit of the tapping head.
Surface Speed Low Carbon Steel High Carbon Steel High Strength and Tool Steel Stainless 303, 304, 316 Stainless 410, 430, 17-4 Hardened Stainless 17-4 Annealed Titanium Alloys Nickel Base Alloys Aluminum Alloys Aluminum Die Cast Magnesium Brass, Bronze Copper Cast Iron
Surface Meters per minute 50 20 15 10 6 10 12 6 50 40 50 40 20 25
Surface Feet per minute 165 65 50 33 20 33 40 20 165 130 165 130 65 80
TO CALCULATE CYCLE TlME PLEASE SELECT EITHER THE RDT25 FOR SMALLER SIZES OR RCT50 FOR UP TO M12.
THEN FILL IN THE YELLOW HI-LITED FIELDS FOR YOUR PARTICULAR APPLICATION USING ONE OF THE CALCULATORS BELOW.
Tapping Head RDT25 with Metric Tap
Tap Sizes M2 to M6
Maximum Speed 4000 RPM
Diameter of Tap in mm
Thread Pitch Metric (mm)
Lead of Tap Metric (Number of Threads in Chamfer)
 
Surface Meters Per Minute (See chart for Material)
Spindle Speed (Rev/Min)
Tap Pitch Feed Rate (mm/min)
 
Tapping Depth (mm)
 
Cycle Time For One Hole (Seconds)
Tapping Head RDT25 with Inch Tap
Tap Sizes #4 to 1/4"
Maximum Speed 4000 RPM
Diameter of Tap in inches
Thread Pitch Inch (Number of threads per inch)
Lead of Tap Inch (Number of Threads in Chamfer)
 
Surface Feet Per Minute (See chart for Material)
Spindle Speed (Rev/Min)
Tap Pitch Feed Rate (inch/min)
 
Tapping Depth (inch)
 
Cycle Time For One Hole (Seconds)
Tapping Head RCT50 with Metric Tap
Tap Sizes M4.5 to M12
Maximum Speed 2500 RPM ER16 and 2300 RPM ER20
Diameter of Tap in mm
Thread Pitch Metric (mm)
Lead of Tap Metric (Number of Threads in Chamfer)
 
Surface Meters Per Minute (See chart for Material)
Spindle Speed (Rev/Min)
Tap Pitch Feed Rate (mm/min)
 
Tapping Depth (mm)
 
Cycle Time For One Hole (Seconds)
Tapping Head RCT60 with Inch Tap
Tap Sizes #10 to 1/2"
Maximum Speed 2500 RPM ER16 and 2300 RPM ER20
Diameter of Tap in inches
Thread Pitch Inch (Number of threads per inch)
Lead of Tap Inch (Number of Threads in Chamfer)
 
Surface Feet Per Minute (See chart for Material)
Spindle Speed (Rev/Min)
Tap Pitch Feed Rate (inch/min)
 
Tapping Depth (inch)
 
Cycle Time For One Hole (Seconds)