M4 Wing Nut (Butterfly Nut), DIN 315

The M4 wing nut (DIN 315) spans 18 to 20 mm across its wings and 8.5 to 10.5 mm high. The thread is M4 × 0.7; the files are simplified and threaded STEP files.

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

• Also searched as: M4 wing nut
• Model id: din315-m4
• Standard: DIN 315:1998 · thread M4 × 0.7, ISO metric coarse, right hand

Files

Part key	Simplified	Threaded
din315-m4	STEP	STEP

Dimensions

Symbol	Name	min	nom	max	Modeled	Rule	Level
P	Thread pitch		0.7		0.7	nominal	L1
d2	Boss diameter at the bearing face	6		8	7	midpoint of min–max	L1
d3	Boss diameter at the top	5.5		7	6.25	midpoint of min–max	L1
e	Wing span	18		20	19	midpoint of min–max	L1
g1	Wing thickness at the tip	1.1		1.9	1.5	midpoint of min–max	L1
g2	Wing thickness at the root	1.7		2.3	2	midpoint of min–max	L1
h	Overall height	8.5		10.5	9.5	midpoint of min–max	L1
m	Boss height	3.2		4.6	3.9	midpoint of min–max	L1
r1	Wing lobe radius		3 ref		3	reference value	L1
r3	Wing root fillet radius (front view)		0.5 ref		0.5	reference value	L1
r4	Wing root fillet radius (plan view)		2 ref		2	reference value	L1
P	Coarse thread pitch		0.7		0.7	nominal	L1
tap_drill	Tap drill diameter		3.3		3.3	nominal	L1
d1	Basic minor diameter		3.2422276		3.2422276	nominal	L1
ch_angle	Chamfered end angle			50	50	single limit (max), modeled at the limit	L2
dh_fine	Clearance hole, fine series		4.3		4.3	nominal	L1
dh_medium	Clearance hole, medium series		4.5		4.5	nominal	L1
dh_coarse	Clearance hole, coarse series		4.8		4.8	nominal	L1

Thread and holes

• Tap drill: 3.3 mm (method: d − P), L1, sources amesweb-tap-drill, rule-tap-drill.
• Clearance hole (ISO 273): close 4.3, normal 4.5, loose 4.8 mm (L1: fine, medium and coarse series (albany-clearance, wikipedia-de-clearance)).

Drawing

As a PDF: CC-DIN315-SZ-M4.pdf.

The M4 wing nut beside the M5

The M4 is the smallest of the 4 DIN 315 wing nuts published here, from M4 to M8.

• Thread pitch (P): 0.7 mm on the M4 wing nut, against 0.8 mm on the M5.
• Boss diameter at the bearing face (d2): 6 to 8 mm on the M4 wing nut, against 8 to 11 mm on the M5.
• Boss diameter at the top (d3): 5.5 to 7 mm on the M4 wing nut, against 7.5 to 9 mm on the M5.
• Wing span (e): 18 to 20 mm on the M4 wing nut, against 24 to 26 mm on the M5.
• Wing thickness at the tip (g1): 1.1 to 1.9 mm on the M4 wing nut, against 1.5 to 2.3 mm on the M5.
• Wing thickness at the root (g2): 1.7 to 2.3 mm on the M4 wing nut, against 2.3 to 2.8 mm on the M5.
• Overall height (h): 8.5 to 10.5 mm on the M4 wing nut, against 11 to 13 mm on the M5.
• Boss height (m): 3.2 to 4.6 mm on the M4 wing nut, against 4 to 6.5 mm on the M5.

Other sizes

• One size larger: M5 Wing Nut (Butterfly Nut), DIN 315, 24 to 26 mm across the wings.

Documents

• CC-DIN315-DS-M4.pdf: M4 datasheet: values with levels, sources
• CC-DIN315-SZ-M4.pdf: M4 drawing: this size's values on the views
• parts.json: the part record of this size (the platform contract)

Sources

albany-clearance, amesweb-tap-drill, fasten-it-din315, fasteners-eu-din315, iso4753-2011-sample, krepcom-din315, rule-basic-minor, rule-tap-drill, wikipedia-de-clearance, wikipedia-iso261. Full citations: the method page and this size's datasheet.

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