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Camera and mic mounts: ISO 518 cold shoe (18.6 mm), Arca-Swiss dovetail (38 mm, 45 degrees), 5/8-27 mic-stand thread + thread files

How wide is a cold shoe and an Arca-Swiss dovetail, and what is the 5/8-27 microphone stand thread? · Standard part · basis: Wikipedia's hot-shoe article and the ISO 518:2006 sample pages for the shoe; Acratech, RRS, Kasson, Leofoto and AstroPix for the dovetail width; Musicalhow for the mic thread; two thread files at the Unified basic profile

Also called: iso 518 hot shoe dimensions, cold shoe width 18.6 mm, arca swiss dovetail width 38 mm, arca swiss 45 degree dovetail, 5/8-27 mic stand thread size, microphone stand thread 5/8 27 vs 3/8 16, accessory shoe dimensions mm, hot shoe foot size, arca swiss clamp width, 5/8-27 thread major diameter mm, mic clip thread stl, 5/8 27 thread pitch 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

length
19.88 mm
width
19.88 mm
height
7.53 mm

Notes

  • ISO 518 (accessory shoe): the standard's basic dimensions are in Figures 1 and 2, which are images in the paywalled standard, so the shoe profile is not drawn. What is readable is the internal size 18.6 (+0.2/-0) x 16.0 (+3/-2) x 2 (+0.15/-0) mm, the 12.5 mm tooth spacing (Wikipedia) and the clearance areas A, B and C and the Ø5 mm contact (sample pages of the standard). A 'cold shoe' is the same mechanical shoe without the centre contact.
  • Arca-Swiss style dovetail: width 38 mm and a 45 degree flank are what the sources agree on. Depth and tolerance are not published, makers' plates measure 38.0 to 38.75 mm (AstroPix), and clamps accept a range; RRS gives a 35 mm base. A fully dimensioned dovetail profile is therefore not available and no profile file is drawn; use your clamp's jaw width and test-fit.
  • 5/8-27 microphone-stand thread: 5/8 in major diameter, 27 threads per inch, described as a unified special thread. Pitch is 25.4 / 27 = 0.9407 mm and the files are drawn at the Unified 60 degree basic profile (H = 0.866025 P, crest flat P/8, root flat P/4), the same method as the lens-thread files. No class or limits for the 5/8-27 were found, so the files are the maximum-material basic shape; add your process allowance on the flanks. The male ring has a bore of Ø10.86 mm and the female ring an outside Ø19.88 mm (wall 2 mm is a design choice); both are 8 turns long.
  • Left out: the NATO accessory rail (STANAG 4694) because no page with its dimensions could be read; Picatinny / MIL-STD-1913 is on picatinny-rail-mil-std-1913. Microphone stand adapters between 5/8-27 and 3/8-16 exist (Musicalhow, retailers); their dimensions were not tabulated.
  • Maker CAD: Really Right Stuff, Leofoto and Neutrik publish drawings per product; none of the pages read carried a rail or shoe drawing as numbers, so none is linked.

Camera and mic mounts: ISO 518 cold shoe (18.6 mm), Arca-Swiss… size chart

itemvalue as publishedsourcenote
ISO 518 camera accessory shoe (cold shoe), internal size18.6 (+0.2/-0) x 16.0 (+3/-2) x 2 (+0.15/-0) mmWikipedia 'Hot shoe' (cites ISO 518:2006)three dimensions in the order printed; the article does not name them
ISO 518, spacing between the two teeth12.5 (+0.4/-0) mmWikipedia 'Hot shoe'
ISO 518 clearance area A (rectangular, Figure 3)12.5 mm in front, 25.0 mm at the back of the shoe; 25.0 mm to the right and left of the centre; nothing higher than 2.0 mm above the top surfaceISO 518:2006 sample pages (iTeh)text of the standard, not an image
ISO 518 clearance area B (circular)diameter 30.0 mmISO 518:2006 sample pages
ISO 518 area C (foot insertion)extends 25.0 mm from the back of the shoe, 20.0 mm wideISO 518:2006 sample pages
ISO 518 centre contact; insulationcontact surface Ø5 mm (Figure 1); insulation resistance not less than 30 MOhm at 0 to 40 CISO 518:2006 sample pagesthe shoe's basic dimensions are in Figures 1 and 2, which are images
Arca-Swiss dovetail, plate width38 mm (1 1/2 in); 38.1 mm in two reader sources; Leofoto 'a consistent 38 mm (1.50 in) width'Acratech, The Last Word, Leofoto, AstroPixAstroPix measured plates at 38.0, 38.05, 38.1, 38.15 and 38.75 mm
Arca-Swiss dovetail, angle45 degreesAcratech; RRSstated as 'the Arca-Swiss style dovetail is 45 degrees'
RRS dovetail, base width35 mm (about 1.38 in) wide baseReally Right StuffRRS calls its product 'RRS 1.5 in Dovetail Standard'; the page does not say what 1.5 in measures, so it is not equated with the 38 mm width
Arca-Swiss dovetail, depth and tolerancenot publishedRRS, Acratech, Kasson, photomacrography.netreaders describe depth as the distance between the dovetail faces' meeting lines but give no value
Microphone stand thread, large5/8-27 ('unified special thread'); major Ø 15.875 mm (5/8 in); pitch 25.4 / 27 = 0.9407 mmMusicalhow (name); diameter and pitch from the designationa reader measured an old stand at 0.622 in outside diameter (not used)
Microphone stand thread, small3/8-16; 1/4-20 on camera gearMusicalhow3/8-16 and 1/4-20 bosses are on camera-thread-bosses-1-4-20
5/8-27 files (Xem-drawn)major Ø15.875, pitch Ø15.264, minor Ø14.857, pitch 0.9407, 7.53 longUnified basic profile (ISO 68-1 / ASME B1.1)limits and class of the 5/8-27 are not published in the sources read; the files are the basic 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.

featureexactmates withfitfiles
5/8-27 external thread (file mic-thread-5-8-27-male-ring)major Ø15.875, pitch Ø15.264, minor Ø14.857 mm, pitch 0.9407 mm, Unified basic profile5/8-27 internal thread of a microphone clip, holder or adapter (file mic-thread-5-8-27-female-ring)designedmic-thread-5-8-27-male*
5/8-27 internal thread (file mic-thread-5-8-27-female-ring)minor Ø14.857, pitch Ø15.264, major Ø15.875 mm, pitch 0.9407 mm, Unified basic profile5/8-27 male thread on a mic stand or boom (file mic-thread-5-8-27-male-ring)designedmic-thread-5-8-27-female*

Where the files are

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

WikipediaHot shoe: ISO 518 internal dimensions 18.6 (+0.2/-0) x 16.0 (+3/-2) x 2 (+0.15/-0) mm; spacing between the two teeth 12.5 (+0.4/-0) mmwebCC BY-SA 4.0 (text); dimensions are facts
iTeh Standards (ISO 518:2006 sample pages)ISO 518:2006 camera accessory shoes: clearance areas A, B, C and contact in the text; Figure 1 and 2 dimensions are imageswebPublisher's page; dimensions are facts
AcratechArca-Swiss vs Bogen / Manfrotto plates: Arca-Swiss style dovetail is 45 degrees, plate 1 1/2 in (38 mm) widewebPublisher's page; dimensions are facts
Really Right StuffWhat is the RRS dovetail standard: 45 degree dovetail, 35 mm (about 1.38 in) wide base on most plates; no depth or tolerance givenwebPublisher's page; dimensions are facts
The Last Word (Jim Kasson)Plate width 38.1 mm (1.5 in) matched to RRS spec in a reader comment; no angle, depth or jaw dimensions givenwebPublisher's page; dimensions are facts
Leofoto USABPL series Arca-type rails: 'a consistent 38mm (1.50 in) width'webPublisher's page; dimensions are facts
AstroPixDovetail sizes: Arca-Swiss 38 mm, measured plates 38.0 to 38.75 mmwebPublisher's page; dimensions are facts
MusicalhowMicrophone stand thread sizes: 5/8-27 unified special thread, 3/8-16, 1/4-20webPublisher's page; dimensions are facts
Bureau of Indian Standards (via Public.Resource.Org)IS 4218 (Part 1):2001 ISO general purpose metric screw threads, basic profile (identical with ISO 68-1:1998): H = 0.866025404 P, 5H/8 = 0.541265877 P, 3H/8 = 0.324759526 PwebPublic.Resource.Org (public law); dimensions are facts
WikipediaUnified Thread Standard (ASME B1.1): same 60 degree basic profile as ISO 68-1webCC BY-SA 4.0 (text); dimensions are facts

Free files

★ Free files 2 parts. Xem Studio design: free to use, print and sell things from; not to be republished as files. Xem Studio Design License. index.json

mic-thread-5-8-27-male-ring5/8-27 UN external thread ring section (microphone-stand thread): Unified basic profile, major Ø15.875, pitch Ø15.264, minor Ø14.857, pitch 0.9407; 7.53 long (8 turns), bore Ø10.857 (wall is a design choice); exact nominal, no toleranceSTEP · STL
mic-thread-5-8-27-female-ring5/8-27 UN internal thread ring section (microphone clip / holder thread): Unified basic profile, minor Ø14.857, pitch Ø15.264, major Ø15.875, pitch 0.9407; 7.53 long (8 turns), outside Ø19.875 (design choice); exact nominal, no toleranceSTEP · STL
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Plain text: sheet.txt · JSON: /api/geometry?object=camera-mic-mounts-cold-shoe-arca-5-8-27

Camera and mic mounts: ISO 518 cold shoe (18.6 mm), Arca-Swiss dovetail (38 mm, 45 degrees), 5/8-27 mic-stand thread + thread files, isometric render of a generated part
Render of mic-thread-5-8-27-female-ring from the free STEP; not to scale.

Fits with

Questions

How wide is a cold shoe?

ISO 518 (via Wikipedia): the internal size is 18.6 (+0.2/-0) x 16.0 (+3/-2) x 2 (+0.15/-0) mm, tooth spacing 12.5 mm.

How wide is an Arca-Swiss plate?

38 mm (1 1/2 in) with a 45 degree dovetail; plates measure 38.0 to 38.75 mm in practice and RRS gives a 35 mm base. Depth is not published.

What is the 5/8-27 thread?

The large microphone-stand thread: 5/8 in (15.875 mm) major diameter, 27 threads per inch (0.9407 mm pitch); a unified special thread. The files draw it at the Unified basic profile.