The M3.5 size of One-Way Security Screws is dimensioned by Trade series (one-way clutch head). The tables below give the dimensional row from the standard, the drill and spanner sizes that go with it, and the assembly torque per property class. The technical drawing on this page redraws to the exact values selected.
M3.5 Dimensional Row (Trade series (one-way clutch head))
| Thread size | Pitch (mm) | Head diameter dk (mm) | Head height k (mm) | Head form | Common length range (mm) | Material | Removable |
|---|---|---|---|---|---|---|---|
| M3.5 | 0.6 | 7.0 | 2.4 | Pan | 10~40 | Steel zinc / A2 | No — permanent |
Spanner & Drive for M3.5 One-Way Security Screws
Drive geometry for M3.5 One-Way Security Screws is given by the row above; match the tool to the listed values.
Hole Sizes for M3.5
| Coarse-thread pitch (ISO 724) | 0.6 mm |
|---|---|
| Through-hole / clearance (ISO 273 medium) | 3.9 mm |
| Tapping drill, coarse thread | 2.9 mm |
Tightening Torque for M3.5
| Class 8.8 (dry, ~µ 0.125) | ≈ 2 Nm |
|---|---|
| Class 10.9 (dry, ~µ 0.125) | ≈ Nm |
| Class 12.9 (dry, ~µ 0.125) | ≈ 3.4 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 M3.5
| Tensile stress area As (ISO 724) | 6.8 mm² |
|---|---|
| Proof load, class 8.8 | 3.9 kN |
| Proof load, class 12.9 | 6.6 kN |
| Min. ultimate tensile load, class 8.8 | 5.4 kN |
Proof load = tensile stress area × the proof stress Sp of the class, per ISO 898-1 — Sp is a lower figure than the yield stress Rp0.2 and the two are not interchangeable. The stress area is computed from this size's own diameter and pitch, so a fine-pitch designation gives the fine-pitch figure. Design the joint so the working preload stays below the proof load of the class selected.
M3.5 One-Way Security Screws Weight
A steel M3.5 one-way security screws at the listed 1,040 mm length weighs approximately 314 g each — about 314 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 M3.5 One-Way Security Screws
- At M3.5 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 M3.5
For M3.5, pair with a M3.5 hex nut (ISO 4032 / DIN 934) and, where used, a M3.5 flat washer (ISO 7089 / DIN 125A) under the head and under the nut.
Custom manufacturing · Made to drawing
Need one-way security screws in a size this table does not list?
This page covers M3.5 one-way security 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.
