# M36 tap drill size

The tap drill for an M36 × 4 metric coarse thread is 32 mm (1.2598 in). It leaves about 77 % thread, the normal range for steel.

## Drill options for M36 × 4

| Drill | Inch | Thread % |
|---|---|---|
| 31.8 mm | 1.2520 | 81 % |
| 31.9 mm | 1.2559 | 79 % |
| 32 mm | 1.2598 | 77 % |
| 32.1 mm | 1.2638 | 75 % |
| 32.2 mm | 1.2677 | 73 % |

## M36 thread data

- Thread: M36 × 4 (coarse)
- Pitch: 4 mm
- Tap drill: 32 mm (1.2598 in)
- Thread engagement: 77 %
- Clearance hole (ISO 273): 37 close, 39 normal, 42 loose (mm)

## Method

Thread % = 76.98 × (D − drill) / P = 76.98 × 4 / 4 = 77 %. Aim for 65–75 % in steel, 75–85 % in aluminium, brass and plastics.

## FAQ

**What size drill for an M36 × 4 tap?**
Use a 32 mm drill. It leaves about 77 % thread engagement.

**What is 32 mm in inches?**
32 mm is 1.2598 inch.

**What size clearance hole for M36?**
ISO 273 gives 37 mm for a close fit, 39 mm normal and 42 mm loose.

**How tight should an M36 bolt be?**
About 2,646 N·m for class 8.8 with dry threads.

Source page: https://machinistcharts.com/tap-drill/m36/
Updated: 2026-10-05
Publisher: MachinistCharts (https://machinistcharts.com)