Studs, DIN 938 and DIN 939 (double-end studs): thread length of the nut end, M5/M6 to M30, nominal lengths — dimension sheet Source: Xem Studio, https://xemstudio.com/objects/studs-din-938-din-939/ (sheet CC BY 4.0) Basis: Böllhoff's DIN 938 and DIN 939 steel 5.8 data sheets (metric coarse thread), with fasten.it's DIN 939 scope text; numbers only Catalog version: 2026-10-20 Sizes: see table below - DIN 938 studs have a screw-in end of about 1 × d (for steel into steel) and DIN 939 studs about 1.25 × d (mainly for cast iron); metric coarse thread, product grade A in the fasten.it scope text. The Böllhoff sheets tabulate (mm): thread pitch P; the thread length of the nut end in three length bands (l up to 125, up to 200, over 200 mm) in the column the sheet calls b (the sheets' b / b1 / b2 labelling is ambiguous in the text read, so it is named here by its function and both sheets print identical values); ds nominal, min and max for DIN 938 (the reduced-shank diameter; M27 prints ds 25 as the sheet does); and the z1 / z2 columns as printed (not defined in the text read). For DIN 939 the screw-in length b1 is the first value after the length bands: M6 7.5, M8 10, M10 12, M12 15, M16 20, M20 25, M24 30, M27 35 mm, which equals 1.25 × d. For DIN 938 the sheet gives the screw-in end only as 'approx. 1 d', so no b1 values are tabulated. - Lengths printed by the sheets (mm). DIN 938: 22, 25, 28, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 105, 110, 115, 120, 125, 130, 135, 140, 150, 160, 170, 180, 190, 200. DIN 939: 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 80, 90, 100, 105, 110, 115, 120, 125, 130, 135, 140, 150, 160, 170, 180, 190, 200. Which length is stocked for which diameter is an availability matrix on the sheets and was not readable, so it is not given. Length tolerances are on the sheets (for example DIN 939 l = 25: 24.58 to 25.42 mm; l = 100: 99.30 to 100.70 mm; l = 200: 199.08 to 200.92 mm). - fasten.it prints DIN 939 as covering metric coarse M4 to M52 and fine M8x1 to M52x3 and its title says '~1.25 d' while its scope says '~1.5 d' for the stud end; its table was not reproducible, so only the Böllhoff values are used and the 1.25 d figure agrees with Böllhoff's b1 values. The DIN 938 sheet as read covers M5 to M30; the DIN 939 sheet as read covers M6 to M27 (the text read may have been cut short, so the standard's range is wider). - No file: a stud is a plain cylinder with a chamfer and a thread, and the plain-cylinder rule for Xem files rules out an envelope. McMaster-Carr lists DIN 939 studs with per-part STEP; the category is linked, not copied. Threaded rod is on threaded-rod-metric-din-976; nuts are on hex-nuts-metric. standard thread pitch P (mm) b1 screw-in end (mm) thread length b, l ≤ 125 (mm) b, 125 < l ≤ 200 (mm) b, l > 200 (mm) ds nominal (mm) ds min / max (mm) z1 min / max; z2 (mm, as printed) DIN 938 M5 0.8 ≈ 1 d (sheet text) 16 22 – 5 4.82 / 5 0.8 / 1.0; 2 DIN 938 M6 1 ≈ 1 d (sheet text) 18 24 – 6 5.82 / 6 1.0 / 1.25; 2.5 DIN 938 M8 1.25 ≈ 1 d (sheet text) 22 28 – 8 7.78 / 8 1.25 / 1.6; 3.2 DIN 938 M10 1.5 ≈ 1 d (sheet text) 26 32 45 10 9.78 / 10 1.5 / 1.9; 3.8 DIN 938 M12 1.75 ≈ 1 d (sheet text) 30 36 49 12 11.73 / 12 1.75 / 2.2; 4.3 DIN 938 M16 2 ≈ 1 d (sheet text) 38 44 57 16 15.73 / 16 2.0 / 2.5; 5 DIN 938 M20 2.5 ≈ 1 d (sheet text) 46 52 65 20 19.67 / 20 2.5 / 3.2; 6.3 DIN 938 M24 3 ≈ 1 d (sheet text) 54 60 73 24 23.67 / 24 3.0 / 3.8; 7.5 DIN 938 M27 3 ≈ 1 d (sheet text) 60 66 79 25 26.67 / 27 3.0 / 3.8; 7.5 DIN 938 M30 3.5 ≈ 1 d (sheet text) 66 72 85 30 29.67 / 30 3.5 / 4.5; 9 DIN 939 M6 1 7.5 18 24 – — — — DIN 939 M8 1.25 10 22 28 – — — — DIN 939 M10 1.5 12 26 32 45 — — — DIN 939 M12 1.75 15 30 36 49 — — — DIN 939 M16 2 20 38 44 57 — — — DIN 939 M20 2.5 25 46 52 65 — — — DIN 939 M24 3 30 54 60 73 — — — DIN 939 M27 3 35 60 66 79 — — — Files elsewhere (not hosted by Xem Studio; license as stated by the publisher): - Böllhoff: DIN 938 stud, steel 5.8, metric coarse thread, threaded end ~ 1 d: thread length by length band, ds, z1, z2, pitch, available lengths 22 to 200 mm — web — Maker data sheet; numbers only — https://eshop-cz.boellhoff.com/out/media/pdf/DIN_938_Stahl_5.8___en.pdf - Böllhoff: DIN 939 stud, steel 5.8, metric coarse thread, threaded end ~ 1.25 d: b1, thread length by length band, lengths 25 to 200 mm with tolerances — web — Maker data sheet; numbers only — https://eshop-cz.boellhoff.com/out/media/pdf/DIN_939_Stahl_5.8___en.pdf - fasten.it: DIN 939 Standard Dimensions for studs with engagement length ~1.25 d (scope, ranges only; the table itself was not reproducible) — web — Reference page; scope text only — https://fasten.it/norms/norm/din_939 No true-size file yet: the published figures do not fix the whole shape; a measured scan is planned. API: https://xemstudio.com/api/geometry?object=studs-din-938-din-939