For wood screws, DIN 7997 is the governing document for the dimensions listed below. Mechanical and performance requirements for this part family are set by its own standards, not by the bolt and screw property-class documents.
DIN 7997 — Scope
DIN 7997 specifies the dimensional requirements for wood screws. Material, surface condition and any performance rating are set by separate documents specific to this part family — ISO 898-1 and ISO 898-2, which govern bolt and nut property classes, do not apply here.
Tolerance & Product Grades
Tolerances for wood screws are given as limits on the individual dimensions in the table rather than as a fastener product grade. Where a general-tolerance class is cited on the drawing instead, it applies to the dimensions not otherwise toleranced.
Dimensions Specified by DIN 7997
| Nominal diameter (mm) | Head diameter dk (mm) | Head height k (mm) | Head type | Pilot hole (mm) | Common length range (mm) | Reference standard | Notes |
|---|---|---|---|---|---|---|---|
| 2.0 | 3.8 | 1.2 | Countersunk | 1.2 | 10~25 | DIN 97 / DIN 7997 | Slotted/cross wood screw, gimlet point |
| 2.5 | 4.7 | 1.5 | Countersunk | 1.5 | 12~30 | DIN 97 / DIN 7997 | Slotted/cross wood screw, gimlet point |
| 3.0 | 5.6 | 1.65 | Countersunk | 1.8 | 12~40 | DIN 97 / DIN 7997 | Slotted/cross wood screw, gimlet point |
| 3.5 | 6.5 | 1.93 | Countersunk | 2.0 | 16~50 | DIN 97 / DIN 7997 | Slotted/cross wood screw, gimlet point |
| 4.0 | 7.5 | 2.2 | Countersunk | 2.3 | 16~70 | DIN 97 / DIN 7997 | Slotted/cross wood screw, gimlet point |
| 4.5 | 8.5 | 2.5 | Countersunk | 2.5 | 20~80 | DIN 97 / DIN 7997 | Slotted/cross wood screw, gimlet point |
| 5.0 | 9.2 | 2.5 | Countersunk | 3.0 | 20~100 | DIN 97 / DIN 7997 | Slotted/cross wood screw, gimlet point |
| 6.0 | 11.0 | 3.0 | Countersunk | 3.5 | 30~120 | DIN 97 / DIN 7997 | Slotted/cross wood screw, gimlet point |
| 8.0 | 14.5 | 4.0 | Countersunk | 5.0 | 40~160 | DIN 97 / DIN 7997 | Slotted/cross wood screw, gimlet point |
Equivalent Standards
Where direct equivalents exist (ISO ↔ DIN, ISO ↔ ASME), they are listed on the parent Wood Screws page. Always confirm against the dimensions on this page, since some "equivalent" standards differ in tolerances and head geometry.
When to Specify DIN 7997
DIN 7997 is still widely used in European mechanical engineering and as a cross-reference on legacy drawings; its ISO equivalent is preferred for new designs.
