ISO 8742 is the standard cited for grooved pins, taper and center-groove types. This page sets out what the standard controls for this part, reproduces the dimensional table supplied against it, and notes the related designations referenced on drawings.
ISO 8742 — Scope
ISO 8742 is "Grooved pins — Third-length centre grooved".
Tolerance & Product Grades
ISO 8742 does not divide grooved pins, taper and center-groove types into product grades. Tolerances are given as limits on the individual dimensions in the table.
Where a general-tolerance class is cited on the drawing instead, it applies to the dimensions not otherwise toleranced.
Dimensions Specified by ISO 8742
| Nominal diameter d (mm) | Type | d_1 (mm) | a (mm) | d1 (mm) | Length range l (mm) | Reference standard |
|---|---|---|---|---|---|---|
| 1.5 mm | Half-length reverse taper grooved pins | 1.5 | 0.2 | 8~20 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 2 mm | Half-length reverse taper grooved pins | 2 | 0.25 | 8~30 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 2.5 mm | Half-length reverse taper grooved pins | 2.5 | 0.3 | 8~30 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 3 mm | Half-length reverse taper grooved pins | 3 | 0.4 | 8~40 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 4 mm | Half-length reverse taper grooved pins | 4 | 0.5 | 10~60 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 5 mm | Half-length reverse taper grooved pins | 5 | 0.63 | 10~60 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 6 mm | Half-length reverse taper grooved pins | 6 | 0.8 | 12~80 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 8 mm | Half-length reverse taper grooved pins | 8 | 1 | 14~100 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 10 mm | Half-length reverse taper grooved pins | 10 | 1.2 | 18~160 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 12 mm | Half-length reverse taper grooved pins | 12 | 1.6 | 26~200 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 16 mm | Half-length reverse taper grooved pins | 16 | 2 | 26~200 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 20 mm | Half-length reverse taper grooved pins | 20 | 2.5 | 26~200 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 25 mm | Half-length reverse taper grooved pins | 25 | 3 | 26~200 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 1.5 mm | Third-length center grooved pins | 1.5 | 0.2 | 8~20 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 1.5 mm | Half-length center grooved pins | 1.5 | 0.2 | 8~20 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 2 mm | Third-length center grooved pins | 2 | 0.25 | 12~30 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 2 mm | Half-length center grooved pins | 2 | 0.25 | 12~30 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 2.5 mm | Third-length center grooved pins | 2.5 | 0.3 | 12~30 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 2.5 mm | Half-length center grooved pins | 2.5 | 0.3 | 12~30 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 3 mm | Third-length center grooved pins | 3 | 0.4 | 12~40 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 3 mm | Half-length center grooved pins | 3 | 0.4 | 12~40 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 4 mm | Third-length center grooved pins | 4 | 0.5 | 18~60 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 4 mm | Half-length center grooved pins | 4 | 0.5 | 18~60 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 5 mm | Third-length center grooved pins | 5 | 0.63 | 18~60 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 5 mm | Half-length center grooved pins | 5 | 0.63 | 18~60 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 6 mm | Third-length center grooved pins | 6 | 0.8 | 22~80 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 6 mm | Half-length center grooved pins | 6 | 0.8 | 22~80 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 8 mm | Third-length center grooved pins | 8 | 1 | 26~100 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 8 mm | Half-length center grooved pins | 8 | 1 | 26~100 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 10 mm | Third-length center grooved pins | 10 | 1.2 | 32~160 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 10 mm | Half-length center grooved pins | 10 | 1.2 | 32~160 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 12 mm | Third-length center grooved pins | 12 | 1.6 | 40~200 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 12 mm | Half-length center grooved pins | 12 | 1.6 | 40~200 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 16 mm | Third-length center grooved pins | 16 | 2 | 45~200 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 16 mm | Half-length center grooved pins | 16 | 2 | 45~200 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 20 mm | Third-length center grooved pins | 20 | 2.5 | 45~200 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 20 mm | Half-length center grooved pins | 20 | 2.5 | 45~200 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 25 mm | Third-length center grooved pins | 25 | 3 | 45~200 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 25 mm | Half-length center grooved pins | 25 | 3 | 45~200 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 1.5 mm | Full-length taper grooved pins | 1.5 | 0.2 | 8~20 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 2 mm | Full-length taper grooved pins | 2 | 0.25 | 8~30 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 2.5 mm | Full-length taper grooved pins | 2.5 | 0.3 | 8~30 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 3 mm | Full-length taper grooved pins | 3 | 0.4 | 8~40 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 4 mm | Full-length taper grooved pins | 4 | 0.5 | 8~60 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 5 mm | Full-length taper grooved pins | 5 | 0.63 | 8~60 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 6 mm | Full-length taper grooved pins | 6 | 0.8 | 10~80 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 8 mm | Full-length taper grooved pins | 8 | 1 | 12~100 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 10 mm | Full-length taper grooved pins | 10 | 1.2 | 14~120 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 12 mm | Full-length taper grooved pins | 12 | 1.6 | 14~120 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 16 mm | Full-length taper grooved pins | 16 | 2 | 24~120 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 20 mm | Full-length taper grooved pins | 20 | 2.5 | 26~120 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 25 mm | Full-length taper grooved pins | 25 | 3 | 26~120 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 1.5 mm | Half-length taper grooved pins | 0.2 | 1.5 | 8~20 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 2 mm | Half-length taper grooved pins | 0.25 | 2 | 8~30 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 2.5 mm | Half-length taper grooved pins | 0.3 | 2.5 | 8~30 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 3 mm | Half-length taper grooved pins | 0.4 | 3 | 8~40 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 4 mm | Half-length taper grooved pins | 0.5 | 4 | 10~60 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 5 mm | Half-length taper grooved pins | 0.63 | 5 | 10~60 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 6 mm | Half-length taper grooved pins | 0.8 | 6 | 10~80 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 8 mm | Half-length taper grooved pins | 1 | 8 | 14~100 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 10 mm | Half-length taper grooved pins | 1.2 | 10 | 14~200 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 12 mm | Half-length taper grooved pins | 1.6 | 12 | 18~200 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 16 mm | Half-length taper grooved pins | 2 | 16 | 26~200 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 20 mm | Half-length taper grooved pins | 2.5 | 20 | 26~200 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 25 mm | Half-length taper grooved pins | 3 | 25 | 26~200 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 |
Companion Standards
ISO 8742 controls the geometry of grooved pins, taper and center-groove types. Surface finish is governed by separate finish standards such as ISO 4042 for electroplating, and corrosion testing by ISO 9227 (neutral salt spray). Mechanical performance is set by the documents specific to this part family — ISO 898-1 and ISO 898-2 apply to bolts, screws, studs and nuts, and not here.
When to Specify ISO 8742
Choose ISO 8742 for international engineering work and OEM supply where ISO standards are the contractual reference. It is the default modern specification for grooved pins, taper and center-groove types.
Custom manufacturing · Made to drawing
Need a pin to this standard in a non-standard size?
Parts built to ISO 8742 are already in the catalog, so a special is usually a variation on existing tooling rather than a new design — which is what keeps the cost down. Made by cold heading or turning.
Minimum order from 2,000 pieces; samples within 7 days of drawing approval.

