M24 × 3 Thread
The chart recommendation gives approximately 77% thread engagement — the conventional target for average materials. It is not the only valid choice; see the options below.
Specification
| Designation | M24 × 3 |
|---|---|
| Thread family | ISO metric coarse |
| Nominal size | M24 |
| Basic major diameter | 0.9449″ / 24 mm |
| Pitch | 3 mm |
| Recommended tap drill | 21 mm (0.8268″ / 21 mm) |
Tap drill options by thread engagement
Any of these standard drills produces a usable engagement for M24 × 3; smaller drills give stronger threads but higher tapping torque. Percentages use the conventional approximation (60° thread form).
| Drill | Decimal in | mm | Approx. engagement |
|---|---|---|---|
| 21 mm — chart recommendation | 0.8268 | 21 | 77% |
| 53/64″ | 0.8281 | 21.034 | 76.1% |
| 27/32″ | 0.8438 | 21.431 | 65.9% |
Nearest drills to the tap drill in other systems
| Drill | Size | vs 21 mm | Resulting engagement |
|---|---|---|---|
| 53/64″ | 0.8281″ / 21.034 mm | +0.034 mm | 76.1% |
Clearance holes
For a bolt or screw of this size to pass through freely. ISO 273 series (fine/medium/coarse), shown as close, normal, and loose.
| Fit | Drill / Ø | Decimal in | mm |
|---|---|---|---|
| close | 25 mm | 0.9843 | 25 |
| normal | 26 mm | 1.0236 | 26 |
| loose | 28 mm | 1.1024 | 28 |
Hex bolt & nut dimensions
For a standard hex bolt (ISO 4014/4017) and style-1 nut (ISO 4032) in this size.
| Wrench / socket size (bolt head) | 36 mm |
|---|---|
| Head height | 15 mm |
| Nut thickness | 21.5 mm |
| Compatible nut | M24 × 3 hex nut |
Basic (nominal) dimensions. See the wrench & socket size charts for all sizes and the metric ↔ SAE socket comparison.
Related threads
- M22 × 2.5 — next size down in metric-coarse