Trapezoidal thread taps for motion threads
Trapezoidal threads transmit force and motion rather than joining parts: on the spindles of presses, vices, lifting tables and machine tools. Their profile is flatter and carries more load than that of a fastener thread. VÖLKEL makes the matching hand taps in HSS-G from Tr 10 x 2 to Tr 36 x 6, as three-piece sets and as single taps.
Why trapezoidal threads are cut in three stages
The pitch of a trapezoidal thread is large and the profile deep. A single tool would have to remove considerably more material at once than on a coarse thread. The cutting work is therefore spread over three tools: taper tap, second tap and bottoming tap. You can buy the complete set or order single taps when one is worn.
Tapping drill
For a trapezoidal thread the drill size does not follow a simple rule of thumb. Values from the VÖLKEL table:
| Thread | Tapping drill |
|---|---|
| Tr 10 x 2 | 8.2 mm |
| Tr 12 x 3 | 9.25 mm |
| Tr 16 x 4 | 12.25 mm |
| Tr 20 x 4 | 16.25 mm |
| Tr 24 x 5 | 19.25 mm |
| Tr 30 x 6 | 24.25 mm |
| Tr 36 x 6 | 30.25 mm |
The complete series comes with every tool as technical information.
Do not confuse with ACME
The metric trapezoidal thread has a flank angle of 30°, the American ACME thread 29°. The difference is small but enough to make the two incompatible. If you are facing an American spindle, check the angle before reaching for a metric tool.
For series production of trapezoidal nuts there are machine nut taps in Tr versions. Tap wrenches for the large squares are under tool holders.
All sizes at a glance
56 articles in 1 series. The article number links straight to the tool.
Hand Tap HSS-G
| Threadnominal size | Tapping drillØ in mm | set of 3 pieces | Rougher | Intermediate | Finisher |
|---|---|---|---|---|---|
| Tr 10 x 2 | 8.2 | 25108 | 25108-1 | 25108-2 | 25108-3 |
| Tr 10 x 3 | 7.5 | 25112 | 25112-1 | 25112-2 | 25112-3 |
| Tr 12 x 3 | 9.25 | 25116 | 25116-1 | 25116-2 | 25116-3 |
| Tr 14 x 3 | 11.25 | 25120 | 25120-1 | 25120-2 | 25120-3 |
| Tr 14 x 4 | 10.5 | 25124 | 25124-1 | 25124-2 | 25124-3 |
| Tr 16 x 4 | 12.25 | 25128 | 25128-1 | 25128-2 | 25128-3 |
| Tr 18 x 4 | 14.25 | 25132 | 25132-1 | 25132-2 | 25132-3 |
| Tr 20 x 4 | 16.25 | 25136 | 25136-1 | 25136-2 | 25136-3 |
| Tr 22 x 5 | 17.25 | 25140 | 25140-1 | 25140-2 | 25140-3 |
| Tr 24 x 5 | 19.25 | 25144 | 25144-1 | 25144-2 | 25144-3 |
| Tr 26 x 5 | 21.25 | 25148 | 25148-1 | 25148-2 | 25148-3 |
| Tr 28 x 5 | 23.25 | 25152 | 25152-1 | 25152-2 | 25152-3 |
| Tr 30 x 6 | 24.25 | 25156 | 25156-1 | 25156-2 | 25156-3 |
| Tr 32 x 6 | 26.25 | 25160 | 25160-1 | 25160-2 | 25160-3 |
Tapping drill: drill diameter recommended by VÖLKEL (Technical Information “Tapping drill sizes”).
