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Ball Stud Dimensions (DIN 71803, Ball 8 to 19 mm)

Guide · Updated October 28, 2026

DIN 71803 covers ball studs for angle joints, ball 8 to 19 mm, form B (rivet) and form C (threaded). Values agree across fasten.it, Fusco, Kipp and Heyd tables.

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Step by step

Pick the ball size: d1 must match the DIN 71805 socket, e.g. 13 mm.
Pick the form: C has a threaded stud and hex; B is a plain rivet stud.
Check the stud: Form C: thread d2, spanner SW; form B: rivet diameter d5 and length l1, short or long.
Check the height: l2 is ball centre to hex face on form C; l3 is the ball end height.

DIN 71803 ball stud dimensions (mm)

Columns: ball d1, form C thread, l2, l3, thread length max, spanner SW, then form B rivet stud diameter d5 and length l1 (short or long).

d1 | Thread (C) | l2 | l3 | Thread length max | SW | d5 (B) | l1 (B)
8 | M5 | 10.2 | 9 | 4 | 7 | 5 | 4 or 7.5
10 | M6 | 12.5 | 11 | 4 | 8 | 6 | 4.5 or 8
13 | M8 | 16.5 | 13 | 5.3 | 11 | 8 | 5 or 10
16 | M10, M12 | 20 | 16 | 7.3 | 13 | 10 | 6 or 13
19 | M14x1.5, M14x2, M16 | 28 | 20 | 10.8 | 16 | 14 | 12 or 18

Worked example: 13 mm stud

A DIN 71803 C13 M8 stud has a 13 mm ball, an 11 mm hex and up to 5.3 mm of M8 thread. It fits a DIN 71805 13 mm socket.

Common problems

Stud loosens: use a lock nut or thread locker on form C.
Wrong ball size: d1 must match the socket.
Rivet stud too short: pick the long form B.

FAQ

What is DIN 71803 used for?

The ball stud half of a DIN 71802 angle joint, mounted on a lever or bracket.

What do form B and C mean?

Form C has a threaded shank with a hex; form B has a plain shank for riveting, in short and long versions.

Why is the stud thread length a max?

Kipp and Heyd list it as l6 max (fasten.it and Fusco as l5); a minimum unthreaded length also applies, so check your supplier.

Are the threads coarse?

Yes except M14x1.5 fine at 19 mm; M14x2 and M16 are also sold.

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General shop information only — follow your drawing, tool maker's data and your quality system.