M3 Low Head Socket Cap Screw, DIN 7984

An M3 low head socket cap screw (DIN 7984) has a head 5.32 to 5.5 mm across and 1.86 to 2 mm tall, driven with a 2 mm hex key. This page has 8 lengths from 6 to 30 mm, each as simplified and threaded STEP.

How these parts are made, and what the levels mean: read the method

• Also searched as: M3 bolt, M3 x 6 to M3 x 30 bolts
• Model id: din7984-m3
• Standard: DIN 7984:2022 · thread M3 × 0.5, ISO metric coarse, right hand

Lengths

Length (mm)	Part key	Simplified	Threaded
6	din7984-m3x6	STEP	STEP
8	din7984-m3x8	STEP	STEP
10	din7984-m3x10	STEP	STEP
12	din7984-m3x12	STEP	STEP
16	din7984-m3x16	STEP	STEP
20	din7984-m3x20	STEP	STEP
25	din7984-m3x25	STEP	STEP
30	din7984-m3x30	STEP	STEP

Dimensions

Symbol	Name	min	nom	max	Modeled	Rule	Level
P	Thread pitch		0.5		0.5	nominal	L1
b	Thread length, l up to 125		12 ref		12	reference value	L1
da	Transition diameter			3.6	3.6	single limit (max), modeled at the limit	L1
dk	Head diameter	5.32		5.5	5.41	midpoint of min–max	L1
ds	Shank diameter	2.86		3	2.93	midpoint of min–max	L1
dw	Bearing face diameter	4.84			4.84	single limit (min), modeled at the limit	L0 (min: one source)
e	Socket width across corners	2.3			2.3	single limit (min), modeled at the limit	L1
k	Head height	1.86		2	1.93	midpoint of min–max	L1
lf	Underhead fillet length			0.51	0.51	single limit (max), modeled at the limit	L1
r	Underhead fillet radius	0.1		0.3	0.2	midpoint of min–max	L0 (max: one source)
s	Socket width across flats	2.02	2	2.1	2.06	midpoint of min–max	L1
t	Socket depth	1.38	1.5	1.62	1.5	nominal	L1
v	Head top chamfer or radius			0.3	0.3	single limit (max), modeled at the limit	L0 (max: one source)
P	Coarse thread pitch		0.5		0.5	nominal	L1
tap_drill	Tap drill diameter		2.5		2.5	nominal	L1
d1	Basic minor diameter		2.458734		2.458734	nominal	L1
ch_angle	Chamfered end angle			50	50	single limit (max), modeled at the limit	L2
dh_fine	Clearance hole, fine series		3.2		3.2	nominal	L1
dh_medium	Clearance hole, medium series		3.4		3.4	nominal	L1
dh_coarse	Clearance hole, coarse series		3.6		3.6	nominal	L1

Thread and holes

• Tap drill: 2.5 mm (method: d − P), L1, sources amesweb-tap-drill, rule-tap-drill.
• Clearance hole (ISO 273): close 3.2, normal 3.4, loose 3.6 mm (L1: fine, medium and coarse series (albany-clearance, wikipedia-de-clearance)).

Drawing

As a PDF: CC-DIN7984-SZ-M3.pdf.

Goes with the M3 low head socket cap screw

• Hex key: 2 mm, the socket's nominal width across flats (s) in the table above.
• ISO 4032 hex nut, the same size as this M3 low head socket cap screw: M3 Hex Nut (Hexagon Nut), ISO 4032 / DIN 934
• ISO 7089 flat washer, the same size as this M3 low head socket cap screw: M3 Flat Washer (Plain Washer), ISO 7089

The M3 low head socket cap screw beside the M4

The M3 is the smallest of the 5 DIN 7984 low head socket cap screws published here, from M3 to M8.

• Thread pitch (P): 0.5 mm on the M3 low head socket cap screw, against 0.7 mm on the M4.
• Thread length, l up to 125 (b): 12 mm (reference) on the M3 low head socket cap screw, against 14 mm (reference) on the M4.
• Transition diameter (da): up to 3.6 mm on the M3 low head socket cap screw, against up to 4.7 mm on the M4.
• Head diameter (dk): 5.32 to 5.5 mm on the M3 low head socket cap screw, against 6.78 to 7 mm on the M4.
• Shank diameter (ds): 2.86 to 3 mm on the M3 low head socket cap screw, against 3.82 to 4 mm on the M4.
• Bearing face diameter (dw): at least 4.84 mm on the M3 low head socket cap screw, against at least 6.2 mm on the M4.
• Socket width across corners (e): at least 2.3 mm on the M3 low head socket cap screw, against at least 2.87 mm on the M4.
• Head height (k): 1.86 to 2 mm on the M3 low head socket cap screw, against 2.66 to 2.8 mm on the M4.

Other sizes

• One size larger: M4 Low Head Socket Cap Screw, DIN 7984, 6.78 to 7 mm head, 2.5 mm hex key.

Documents

• CC-DIN7984-DS-M3.pdf: M3 datasheet: values with levels, lengths, sources
• CC-DIN7984-SZ-M3.pdf: M3 drawing: this size's values on the views
• parts.json: the part record of every length (the platform contract)

Sources

albany-clearance, amesweb-tap-drill, aspen-din7984, aspen-din7984-pages, fasten-it-din7984, fasteners-eu-din7984, fasteners-eu-din7984-lengths, globalfastener-din7984, iso4753-2011-sample, rule-basic-minor, rule-din7984-lg, rule-tap-drill, wikipedia-de-clearance, wikipedia-iso261. Full citations: the method page and this size's datasheet.

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