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O-ring cord stock sizes: 0.070 to 0.500 in and 1.5 to 8.4 mm diameters (round), AS568 series cross-reference

What diameters does O-ring cord stock come in, and which AS568 O-ring series does each match? · Standard part · basis: McMaster-Carr's printed cord stock width list (inch and metric) and Marco Rubber's cord ranges; the AS568 cross-sections are from as568-o-rings. Numbers only

Also called: o-ring cord stock sizes, o ring cord diameter chart, 0.139 cord stock, 3.53 mm o-ring cord, o-ring cord 5 mm, viton cord stock sizes, buna-n cord stock diameter, o ring cord metric sizes, cord stock for as568 -2xx, 1/4 o-ring cord stock, o-ring cord 2.4 mm

Exact dimensions. Every file is drawn at true size with no tolerance added. The holes and pins that meet another part are listed below under Mating features, with the fit each joint needs; open those by your process's clearance before making the part. Mating features

sizes: 23 in table

Notes

McMaster-Carr's cord stock page lists these 'For Cord Stock Width' diameters: inch 0.07, 0.103, 0.139, 0.21, 0.275, 0.312, 0.313, 0.375, 0.5 and metric 1.5, 1.6, 2, 2.4, 2.5, 3, 3.5, 4, 5, 5.7, 8.4 mm. 0.312 and 0.313 are both printed, and the page does not say which diameters come in which materials. The inch values 0.070 / 0.103 / 0.139 / 0.210 / 0.275 in are the five AS568 cross-section series (-0xx to -4xx); the mm conversions are inch x 25.4.
Marco Rubber's page gives ranges only: round cord from 0.039 to 2.000 in, square from 0.099 to 1.000 in, 4-lobed X-ring cord from 0.103 to 1.000 in, in durometers 40 to 90. It prints no step list, tolerances or lengths.
Tolerances, standard lengths and colours were not printed in the sources read, so none are given. For a ring cut and spliced from cord the cross-section you need is the one in the groove tables: oring-gland-static-radial-as568, oring-gland-dynamic-reciprocating-as568 (inch) and oring-grooves-metric (mm cross-sections 1.0 to 5.7).
No file: cord is a plain cylinder of the stated diameter and any length, so it is not drawn. McMaster-Carr sells cord stock by the foot; its category page is linked, not copied.

O-ring cord stock sizes: 0.070 to 0.500 in and 1.5 to 8.4 mm… size chart

system	diameter	mm	source	AS568 series / note
inch	0.070 in	1.78	McMaster-Carr cord stock width list	AS568 -0xx series (CS 1.78 mm per the as568 page)
inch	0.103 in	2.62	McMaster-Carr cord stock width list	AS568 -1xx series (CS 2.62 mm per the as568 page)
inch	0.139 in	3.53	McMaster-Carr cord stock width list	AS568 -2xx series (CS 3.53 mm per the as568 page)
inch	0.210 in	5.33	McMaster-Carr cord stock width list	AS568 -3xx series (CS 5.33 mm per the as568 page)
inch	0.275 in	6.99	McMaster-Carr cord stock width list	AS568 -4xx series (CS 6.99 mm per the as568 page)
inch	0.312 in	7.92	McMaster-Carr cord stock width list	not an AS568 cross-section
inch	0.313 in	7.95	McMaster-Carr cord stock width list	not an AS568 cross-section
inch	0.375 in	9.52	McMaster-Carr cord stock width list	not an AS568 cross-section
inch	0.500 in	12.70	McMaster-Carr cord stock width list	not an AS568 cross-section
metric	1.5 mm	1.5	McMaster-Carr cord stock width list	not an AS568 cross-section
metric	1.6 mm	1.6	McMaster-Carr cord stock width list	not an AS568 cross-section
metric	2 mm	2	McMaster-Carr cord stock width list	not an AS568 cross-section
metric	2.4 mm	2.4	McMaster-Carr cord stock width list	not an AS568 cross-section
metric	2.5 mm	2.5	McMaster-Carr cord stock width list	not an AS568 cross-section
metric	3 mm	3	McMaster-Carr cord stock width list	not an AS568 cross-section
metric	3.5 mm	3.5	McMaster-Carr cord stock width list	not an AS568 cross-section
metric	4 mm	4	McMaster-Carr cord stock width list	not an AS568 cross-section
metric	5 mm	5	McMaster-Carr cord stock width list	not an AS568 cross-section
metric	5.7 mm	5.7	McMaster-Carr cord stock width list	not an AS568 cross-section
metric	8.4 mm	8.4	McMaster-Carr cord stock width list	not an AS568 cross-section
inch (range)	round 0.039 to 2.000 in	0.99 to 50.80	Marco Rubber cord page	range as printed; no list of steps
inch (range)	square 0.099 to 1.000 in	2.51 to 25.40	Marco Rubber cord page	square cross-section
inch (range)	4-lobed X-ring cord 0.103 to 1.000 in	2.62 to 25.40	Marco Rubber cord page	quad-ring / X-ring profile

Mating features

Drawn at the exact size. Open press, slide, run and socket features by your process's clearance (tolerances by process); leave designed gaps and clamp fits as drawn.

feature	exact	mates with	fit	files
diameter	0.070 / 0.103 / 0.139 / 0.210 / 0.275 in (1.78 / 2.62 / 3.53 / 5.33 / 6.99 mm)	AS568 O-ring cross-section by series (-0xx to -4xx) and its groove on the oring-gland pages	designed	all
metric diameter	1.5 / 1.6 / 2 / 2.4 / 2.5 / 3 / 3.5 / 4 / 5 / 5.7 / 8.4 mm (McMaster list)	metric O-ring groove on oring-grooves-metric (cross-sections 1.0 to 5.7 mm)	designed	all

Where the files are

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

McMaster-Carr	O-ring cord stock (for cord width filter: inch and metric diameters as listed) (free STEP/IGES per part, for your own design use; no redistribution)	STEP, IGES, PDF	McMaster-Carr site terms: personal design use, no redistribution verify
Marco Rubber & Plastics	O-ring cord: round 0.039 to 2.000 in, square 0.099 to 1.000 in, 4-lobed X-ring cord 0.103 to 1.000 in; durometers 40 to 90	web	Publisher's page; dimensions are facts

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=o-ring-cord-stock-sizes

Schematic, not to scale.