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Self-drilling screws DIN 7504: hexagon washer head (type K) and pan / countersunk heads (N, P), ST2.2–ST6.3: head diameter, height, drill-point diameter, drilling depth

What are the hex washer head dimensions (across flats, washer diameter, height) of an ST4.8 or ST5.5 self-drilling screw, and how thick a sheet does it drill? · Standard part · basis: fasten.it's DIN 7504 tables (09/1995, now cancelled): types K, N and P with the page's own column letters; numbers only

Also called: din 7504 dimensions, st4.8 hex washer head dimensions, st5.5 self drilling screw head, st6.3 hex washer head across flats, din 7504 k head diameter, self drilling screw 4.8 mm head, st4.2 self drilling screw head size, din 7504 drilling depth, st5.5 drilling capacity, din 7504 type n, hex washer head screw wrench size 8 mm

Exact dimensions. True size, with no tolerance added.

sizes
21 in table

Notes

  • Millimetres. DIN 7504 is the (cancelled) standard for self-drilling tapping screws; fasten.it still prints it. Sizes ST2.2 to ST6.3. The page does not define its column letters, so none is interpreted beyond the names the page gives. For type K (hexagon washer head) the columns are P (pitch), h min, k (max / min), dc (min – max), s (min – max) and dp max; read from the shape of the head, dc is the washer diameter and s the hexagon width across flats, but the page does not say so. Types N and P print k and dk (min – max) and dp max; type R is printed identically to P; type L (hex head with slot) was read too and is not tabulated.
  • 'Drilling depth, from – to' is printed as a row of seven value pairs without clear column alignment; the pairs were matched to ST2.9, 3.5, 3.9, 4.2, 4.8, 5.5, 6.3 in the order printed, so treat that column as read in order, not as a verified table. The page's heading for the block is 'Drilling depth (sheet, plate, thickness)' with a drill-point figure; the numbers are not interpreted further. The standard's minimum grip length (lg) table is printed without headers and is not used.
  • Compare with the drilling ranges makers print for inch Tek points on tek-self-drilling-screw-drill-points: the two sets are not the same measure and are not converted.
  • No file: head chamfers, washer face, drill-flute and thread geometry are not published as numbers on the page; a drawing from k, dc and s alone would be an invented shape.

Self-drilling screws DIN 7504: hexagon washer head (type K) and pan… size chart

head typethreadPk (max / min)dc or dk (min – max)s (min – max; reads as width across flats)h mindp maxdrilling depth from – to (mm, read in order)
Type K (hexagon washer head)ST2.91.1k 2.8 / 2.5dc 5.8 – 6.3s 3.82 – 4h min 0.4dp max 2.30.7 – 1.9
Type K (hexagon washer head)ST3.51.3k 3.4 / 3dc 7.6 – 8.3s 5.32 – 5.5h min 0.6dp max 2.80.7 – 2.25
Type K (hexagon washer head)ST3.91.3k 3.4 / 3dc 7.6 – 8.3s 5.32 – 5.5h min 0.6dp max 3.10.7 – 2.4
Type K (hexagon washer head)ST4.21.4k 4.1 / 3.6dc 8.1 – 8.8s 6.78 – 7h min 0.8dp max 3.61.75 – 3
Type K (hexagon washer head)ST4.81.6k 4.3 / 3.8dc 9.8 – 10.5s 7.78 – 8h min 0.9dp max 4.11.75 – 4.4
Type K (hexagon washer head)ST5.51.8k 5.4 / 4.8dc 10 – 11s 7.78 – 8h min 1dp max 4.81.75 – 5.25
Type K (hexagon washer head)ST6.31.8k 5.9 / 5.3dc 12.2 – 13.5s 9.78 – 10h min 1dp max 5.82 – 6
Type NST2.20.8k 1.6 / 1.4dk 3.7 – 4——dp max 2.3—
Type NST2.91.1k 2.4 / 2.15dk 5.3 – 5.6——dp max 2.80.7 – 1.9
Type NST3.51.3k 2.6 / 2.35dk 6.64 – 7——dp max 3.10.7 – 2.25
Type NST4.21.4k 3.1 / 2.8dk 7.64 – 8——dp max 3.61.75 – 3
Type NST4.81.6k 3.7 / 3.4dk 9.14 – 9.5——dp max 4.11.75 – 4.4
Type NST5.51.8k 4 / 3.7dk 10.57 – 11——dp max 4.81.75 – 5.25
Type NST6.31.8k 4.6 / 4.3dk 11.57 – 12——dp max 5.82 – 6
Type P (also type R, identical table)ST2.20.8k max 1.1dk 3.5 – 3.8——dp max 2.3—
Type P (also type R, identical table)ST2.91.1k max 1.7dk 5.2 – 5.5——dp max 2.80.7 – 1.9
Type P (also type R, identical table)ST3.51.3k max 2.35dk 6.9 – 7.3——dp max 3.10.7 – 2.25
Type P (also type R, identical table)ST4.21.4k max 2.6dk 8 – 8.4——dp max 3.61.75 – 3
Type P (also type R, identical table)ST4.81.6k max 2.8dk 8.9 – 9.3——dp max 4.11.75 – 4.4
Type P (also type R, identical table)ST5.51.8k max 3dk 9.9 – 10.3——dp max 4.81.75 – 5.25
Type P (also type R, identical table)ST6.31.8k max 3.15dk 10.9 – 11.3——dp max 5.82 – 6

Where the files are

Other publishers' files are linked, not hosted. "verify" = check the license at the link before commercial use.

fasten.itDIN 7504 self-drilling tapping screws, 09/1995 (cancelled): types K (hexagon washer head), L, N, P, R; ST2.2 to ST6.3: P, h, k, dc, s, dk, dp and drilling depthwebReference page; numbers only. The page does not define the column letters

Xem scan

File coming

No downloadable true-size file yet: the published figures do not fix the whole shape, and Xem never guesses a number. A measured scan is planned; request it and it moves up.

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Plain text: sheet.txt · JSON: /api/geometry?object=self-drilling-screws-din-7504-heads

Schematic, not to scale.

Fits with

Questions

What is the width across flats of an ST4.8 hex washer head self-drilling screw?

DIN 7504 type K: the s column is 7.78 – 8 mm for ST4.8 (and ST5.5), the washer column dc 9.8 – 10.5 mm, height k 4.3 max / 3.8 min.

How thick a sheet does an ST5.5 self-drilling screw drill?

The page's drilling-depth row, read in order, gives 1.75 – 5.25 mm for ST5.5 (matched by position, not by column header).

Is DIN 7504 still current?

fasten.it marks the 09/1995 edition as cancelled; the page remains a useful size table.