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Hexagon Turnbuckle Nut Dimensions (DIN 1479, M6 to M30)
Guide · Updated October 28, 2026
DIN 1479 covers hexagon turnbuckle nuts with right- and left-hand thread, from M6 to M30. Values agree across the DIN 1479 text, Fuller Fasteners, Fastenerdata and fasteners.eu. Check your supplier for critical work.
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Step by step
- Match the thread: One end is left-hand, one right-hand; the left end is marked L or by a groove over the corners.
- Check engagement: Screw each rod in at least t, using the sight hole to check it.
- Pick the wrench: Use s from the chart.
- Adjust: Turning the body pulls both rods in or out, up to the adjustment range.
DIN 1479 turnbuckle nut dimensions (mm)
Columns: thread d1, length l (nominal), width across flats s, thread length m, thread depth t (min engagement), recess d2, adjustment range, width across corners e min.
- Size | l | s | m | t | d2 | adjust | e min
- M6 | 30 | 10 | 22.5 | 9.5 | — | 15 | 11.05
- M8 | 35 | 13 | 25 | 12 | — | 15 | 14.38
- M10 | 45 | 16 | 33 | 14 | — | 21 | 17.77
- M12 | 55 | 18 | 40 | 17 | — | 25 | 20.03
- M16 | 75 | 24 | 55 | 22 | — | 35 | 26.75
- M20 | 95 | 30 | 24 | 26 | 21 | 47 | —
- M24 | 115 | 36 | 29 | 31 | 26 | 57 | —
- M30 | 125 | 46 | 36 | 38 | 32 | 53 | —
Worked example: M12 turnbuckle
An M12 DIN 1479 body is 55 mm long with an 18 mm hex. Thread each rod in at least 17 mm (t); the body gives up to 25 mm of adjustment.
Common problems
- Will not tighten: one rod has the wrong hand; the left end is marked L or grooved.
- Rod pulls out: engagement is less than t; check the sight hole.
- Wrong wrench: check the s column (M10 is 16, M12 is 18).
FAQ
What is DIN 1479?
A hexagon turnbuckle body (Spannschlossmutter) with one right-hand and one left-hand thread, M6 to M30, product grade A.
Is it a coupling nut?
No. A DIN 6334 coupling nut has one thread direction all the way through; DIN 1479 is opposite-handed for tensioning.
Why is e dashed at M20 to M30?
The DIN text and Fastenerdata give 32.95/39.55/50.85, but fasteners.eu gives 33.53/39.98/51.28, so we dash it.
What is m?
Up to M16 the threads overlap and m is the thread length; from M20 the body has a central recess d2 and m is the thread length per end.
Related guides and calculators
- Lifting eye bolts (DIN 580)
- Tube turnbuckles (DIN 1478)
- Forged turnbuckles (DIN 1480)
- Hex coupling nuts (DIN 6334)
- Pipe nuts (DIN 431)
- Hex nuts (ISO 4032)
- How to cut left-hand threads
- Wrench size chart
- All free machinist calculators
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General shop information only — follow your drawing, tool maker's data and your quality system.