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Round Head Grooved Pin Dimensions (ISO 8746, 1.4 to 20 mm)

Guide · Updated October 28, 2026

ISO 8746 covers round head grooved pins (grooved rivets), 1.4 to 20 mm. Values agree across the fasteners.eu and globalfastener ISO 8746 tables. fasten.it (DIN EN ISO 8746) also agrees on dk max, k min, r and c. Check your supplier for critical work.

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Step by step

Pick the pin size: d, 1.4 to 20 mm; drill the hole to d, tolerance H11.
Check the head: dk is the head diameter and k the head height, both min to max. r is the head radius.
Check the point: c is the chamfer (type A) or pilot (type B) length at the end.
Order it: Designate as Grooved pin ISO 8746 - 3 x 6 - St.

ISO 8746 round head grooved pin dimensions (mm)

Columns: nominal d, shank d min (max = nominal), head diameter dk max and min, head height k max and min, head radius r ≈, point length c.

d | d min | dk max | dk min | k max | k min | r | c
1.4 | 1.35 | 2.6 | 2.2 | 0.9 | 0.7 | 1.4 | 0.42
1.6 | 1.55 | 3 | 2.6 | 1.1 | 0.9 | 1.6 | 0.48
2 | 1.95 | 3.7 | 3.3 | 1.3 | 1.1 | 1.9 | 0.6
2.5 | 2.425 | 4.6 | 4.2 | 1.6 | 1.4 | 2.4 | 0.75
3 | 2.925 | 5.45 | 4.95 | 1.95 | 1.65 | 2.8 | 0.9
4 | 3.9 | 7.25 | 6.75 | 2.55 | 2.25 | 3.8 | 1.2
5 | 4.9 | 9.1 | 8.5 | 3.15 | 2.85 | 4.6 | 1.5
6 | 5.9 | 10.8 | 10.2 | 3.75 | 3.45 | 5.7 | 1.8
8 | 7.85 | 14.4 | 13.6 | 5 | 4.6 | 7.5 | 2.4
10 | 9.85 | 16 | 14.9 | 7.4 | 6.5 | 8 | 3
12 | 11.8 | 19 | 17.7 | 8.4 | 7.5 | 9.5 | 3.6
16 | 15.8 | 25 | 23.7 | 10.9 | 10 | 13 | 4.8
20 | 19.8 | 32 | 30.7 | 13.9 | 13 | 16.5 | 6

Worked example: 3 mm grooved rivet

To fix a nameplate with a 3 x 6 ISO 8746 pin, drill a 3 mm H11 hole. The head is 4.95 to 5.45 mm across and 1.65 to 1.95 mm high, so leave about 5.5 mm of clear face around the hole.

Common problems

Pin loose: hole oversize; drill to d, do not ream larger.
Head cracks the plate: support the back and drive square.
Pin bottoms out: the hole must be deeper than l.

FAQ

What is ISO 8746?

A round head grooved pin, also called a grooved rivet or drive stud, 1.4 to 20 mm. You drive it into a plain drilled hole to fix nameplates, brackets or springs. It replaced DIN 1476.

Why is there no expanded diameter column?

The sources give different d2 values. fasten.it lists 20.25 at 20 mm and globalfastener a min to max range, so we left d2 out. Ask your supplier for it.

What about ISO 8747 countersunk head?

The sources disagree on its head diameter at 3 mm and 20 mm, so it has no chart yet.

Which edition is this?

ISO 8746:1997. The 2025 edition removes 1.4 and 1.6 mm and recalculates dk, so check your supplier for 2025 stock.

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