Dimensional and assembly data for M6 Low Head Socket Cap Screws to DIN 7984. Includes head size and width across flats, clearance-hole and tapping-drill diameters, tightening torque per property class, and the sizes to step up or down to when the joint requires it.
M6 Dimensional Row (DIN 7984)
| Size | Pitch P (mm) | b (mm) | Head diameter dk (mm) | da (mm) | ds_min (mm) | e (mm) | Head height k (mm) | r (mm) | Hex socket s (mm) | t (mm) | v (mm) | dw (mm) | Length range l (mm) | Reference standard |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| M6 | 1.0 | 18 | 10.0 | 6.8 | 5.82 | 4.58 | 4.0 | 0.25 | 4.0 | 3.0 | 0.6 | 9.2 | 10~40 | DIN 7984 |
Spanner & Drive for M6 Low Head Socket Cap Screws
The hex socket for M6 Low Head Socket Cap Screws is shown in the spec table — use the matching Allen / hex key (an ISO 2936 hex key set covers the full range). A T-handle key gives the most feel when you are judging preload by hand; anything repeated across a batch wants a torque-controlled driver instead.
Hole Sizes for M6
| Coarse-thread pitch (ISO 724) | 1 mm |
|---|---|
| Through-hole / clearance (ISO 273 medium) | 6.6 mm |
| Tapping drill, coarse thread | 5 mm |
Tightening Torque for M6
| Class 8.8 (dry, ~µ 0.125) | ≈ 10 Nm |
|---|---|
| Class 10.9 (dry, ~µ 0.125) | ≈ 15 Nm |
| Class 12.9 (dry, ~µ 0.125) | ≈ 17 Nm |
Indicative dry-joint values. Lubrication can lower the required torque by 15–25%. Always confirm against the joint design, especially when going up a strength class.
Proof Load & Strength for M6
This is a reduced-height head. The head, not the thread, limits what the screw will carry — ISO 7380-1 caps a button head at roughly 80% of the thread's capacity — so the thread's proof load overstates the assembly. Size the joint on the head, or use a cap screw where the full class strength is needed.
M6 Low Head Socket Cap Screws Weight
A steel M6 low head socket cap screws at the listed 1,040 mm length weighs approximately 641 g each — about 641 kg per 1,000 pieces. Stainless A2/A4 weighs roughly the same (density 7.9–8.0 g/cm³).
Actual weight varies slightly with head form, thread and finish; use this figure for freight estimation only.
Installation Tips for M6 Low Head Socket Cap Screws
- Use a quality Allen key fully seated in the socket — partial engagement is the most common cause of stripped sockets at this size.
- For countersunk and button-head variants, chamfer the through-hole to seat the head flush without preloading the head/shank fillet.
When to Step Up or Down from M6
When the joint preload approaches the proof load of M6 class 8.8, step up to M8 class 8.8 (or move to M6 class 10.9). When the joint is over-specified, M5 often saves weight and cost without losing the safety margin.
Custom manufacturing · Made to drawing
Need low head socket cap screws in a size this table does not list?
This page covers M6 low head socket cap screws. Material and finish are usually what drives a special — a grade the standard part is not stocked in, or a coating chosen against a salt-spray figure instead of a default. Made by cold heading or warm forging.
Minimum order from 2,000 pieces; samples within 7 days of drawing approval.
