M1.6 Hex Bolts (ISO 4014 / ISO 4017) are specified by thread size, length and head dimensions. The M1.6 row from the standard is reproduced below, followed by the drill sizes, spanner size and torque values used when installing this size.
M1.6 Dimensional Row (ISO 4014 / ISO 4017)
| Size | Pitch coarse (mm) | Width across flats s (mm) | Width across corners e min (mm) | Head height k nom (mm) | Nominal diameter d (mm) | Reference standard | Notes |
|---|---|---|---|---|---|---|---|
| M1.6 | 0.35 | 3.2 | 3.48 | 1.1 | 1.6 | ISO 4014/4017 | Fully threaded |
Spanner & Drive for M1.6 Hex Bolts
M1.6 Hex Bolts have a width across flats of 3.2 mm — fit a 3.2 mm open-ended spanner or socket. Use a 6-point socket for tight clearances and to reduce rounding; for repeated assembly choose a torque wrench so the joint preload is repeatable.
Common Applications for M1.6 Hex Bolts
M1.6 Hex Bolts are commonly specified for precision instruments, small machinery and consumer-electronics enclosures.
Installation Tips for M1.6 Hex Bolts
- Use a 6-point socket where access allows — 12-point sockets are more prone to rounding the corners on smaller sizes.
- On flanged or serrated variants, do NOT add a separate flat washer — the flange already spreads the load and the washer can defeat the locking serrations.
- At M1.6 the joint is sensitive to over-torque — use a torque-limiting driver and check the head doesn't bury into a softer counterpart.
Mating Parts for M1.6
For M1.6, pair with a M1.6 hex nut (ISO 4032 / DIN 934) and, where used, a M1.6 flat washer (ISO 7089 / DIN 125A) under the head and under the nut.
