Collets for Auto-Reversing Tapping Heads
Secure taps in auto-reversing tapping heads with these collets. They hold inch and metric taps with shanks that meet ANSI standards.
Collets for Tapmatic and for McMaster-Carr approved tapping heads are made of rubber that compresses to hold a range of tap sizes. Steel jaw inserts add strength and maintain grip as these collets squeeze the tap shank.


| For Tap Size, Inch | For Tap Size, Metric | For Tap Size, Pipe | For Shank Dia. | Body Dia. | Overall Lg. | Material | Jaw Insert Material | Each | |
For RX 30, RXII 30 Series | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| No. 0 to No. 8 | M1.6 to M4 | __ | 0.094"-0.177" | 0.59" | 0.468" | Rubber | Steel | 25305A31 | 0000000 |
| No. 10 to 1/4" | M4 to M6 | __ | 0.177"-0.256" | 0.59" | 0.468" | Rubber | Steel | 25305A32 | 000000 |
For RX 50, RXII 50 Series | |||||||||
| No. 0 to 1/4" | M3 to M6 | __ | 0.139"-0.257" | 0.941" | 1/2" | Rubber | Steel | 25305A33 | 000000 |
| 5/16" to 1/2" | M7 to M12 | 1/16 | 0.253"-0.383" | 0.941" | 1/2" | Rubber | Steel | 25305A34 | 000000 |
Jacobs Taper Auto-Reversing Tapping Heads

Cut internal threads without stopping your machine—these tapping heads reverse nearly twice as fast as they cut so you can move to your next hole faster. When you lift the quill, they automatically back the tap out, which also helps reduce wear on your machine and taps. A built-in ball clutch lets you set the torque for your tap size and workpiece material, keeping threads clean and preventing tap breakage. Mount them to a Jacobs taper arbor on manual mills and drill presses. Add a stop bar to your setup if you can’t brace the stop arm on your machine.
Choose your tapping head based on your tap size and maximum speed. For small holes and soft material, select a head that runs at higher speeds. For large holes and hard material, select a head with a larger tap size since they generate greater torque.
Collets (sold separately) are required to connect Tapmatic tapping heads to your tap.
| Jacobs Taper No. | Max. Speed, rpm | For Tap Size, Inch | For Tap Size, Metric | For Tap Size, Pipe | For Tap Thread Direction | Material | Manufacturer Model No. | Includes | Each | |
Tapmatic | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| 33 | 2,000 | No. 0 to 1/4" | M1.4 to M7 | __ | Right Hand | Steel | RXII 30 | Two Wrenches, Stop Arm | 8317A65 | 0000000 |
| 33 | 1,500 | No. 0 to 1/2" | M3 to M12 | 1/16 | Right Hand | Steel | RXII 50 | Two Wrenches, Stop Arm | 8317A66 | 00000000 |

| For Tap Size, Inch | For Tap Size, Metric | For Tap Size, Pipe | For Shank Dia. | Body Dia. | Overall Lg. | Material | Jaw Insert Material | Each | |
For Tapmatic RXII 30 Series | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| No. 0 to No. 8 | M1.6 to M4 | __ | 0.094"-0.177" | 0.59" | 0.468" | Rubber | Steel | 25305A31 | 0000000 |
| No. 10 to 1/4" | M4 to M6 | __ | 0.177"-0.256" | 0.59" | 0.468" | Rubber | Steel | 25305A32 | 000000 |
For Tapmatic RXII 50 Series | |||||||||
| No. 0 to 1/4" | M3 to M6 | __ | 0.139"-0.257" | 0.941" | 1/2" | Rubber | Steel | 25305A33 | 000000 |
| 5/16" to 1/2" | M7 to M12 | 1/16 | 0.253"-0.383" | 0.941" | 1/2" | Rubber | Steel | 25305A34 | 000000 |



























