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Spur gears, 16 diametral pitch (DP): 12 to 60 teeth, 14.5° and 20° involute, pitch / outside / root diameter and STEP/STL

What is the pitch diameter, outside diameter and root diameter of a 16 DP spur gear, and how many teeth does it have? · Hardware · basis: AGMA / ANSI diametral-pitch relations: pitch Ø = N / DP, outside Ø = (N + 2) / DP, minimum dedendum per ANSI B6.1 (20° coarse), Machinery's Handbook (14.5°) and ANSI B6.7 (20 DP and finer); true involute flanks generated point by point

Also called: 16 dp spur gear, 16 pitch spur gear, 16 diametral pitch gear dimensions, 16 dp gear pitch diameter, 16 dp 20 tooth gear, 16 dp gear stl, 16 dp gear step file, diametral pitch gear calculator, spur gear outside diameter formula dp, 14.5 degree pressure angle spur gear, 20 degree pressure angle spur gear, pitch diameter = teeth / dp, 16 pitch gear whole depth, inch pitch spur gear cad, 16p spur gear

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
13 in table

Notes

  • 16 diametral pitch (DP) means 16 teeth per inch of pitch diameter: pitch diameter = N / 16 in, outside diameter = (N + 2) / 16 in, circular pitch = π / 16 = 0.1963 in (4.987 mm), addendum 1 / 16 = 0.0625 in (1.587 mm), tooth thickness on the pitch circle π / (2 × 16) = 0.0982 in. Centre distance of two gears = (N1 + N2) / (2 × 16) in = 0.794 (N1 + N2) mm. Module equivalent: 1.5875. A 16 DP gear does not mesh with a metric module gear unless the two are within rounding of each other; use the module pages for metric gears.
  • Below 20 DP the coarse-pitch proportions apply: 20° (ANSI B6.1) dedendum 1.25 / P, whole depth 2.25 / P; 14.5° dedendum 1.157 / P, whole depth 2.157 / P (all minimum values), so the 14.5° root circle is a little larger. The table lists root and base diameters for both pressure angles so a hob or a CAD mate can be checked. 14.5° and 20° gears do not mesh: the pair must have the same DP and the same pressure angle. 14.5° is the older Brown & Sharpe / Boston Gear stock form (undercut below 32 teeth), 20° the current standard (undercut below 18 teeth).
  • Files: 26 gears, a 14.5° and a 20° gear for each of the 13 tooth counts, as one extruded solid with a plain bore. Flanks are the true involute of the base circle, tooth thickness on the pitch circle half the circular pitch (no backlash), outside and root diameters as in the table, the root circle held at the root diameter for every tooth count (the flank is carried down to it; the real root fillet and trochoid are not modelled). Example choices (not published values): face width 1/2 in (12.70 mm), which is 8 / DP rounded to 1/16 in, and a bore of about a third of the root diameter picked from 1/16, 1/8, 3/16, 1/4, 5/16, 3/8, 1/2, 5/8, 3/4, 1 in. Hubs, keyways and set-screw holes are not drawn. Teeth below 32 (14.5°) and 18 (20°) are drawn without profile shift, so they are undercut-prone as real unshifted gears are.
  • Stock tooth counts: the 12 to 60 range covers common stock gears (Boston Gear lists 16 DP 14.5° 14-tooth with 0.875 in pitch diameter, 1 in outside diameter, 0.5 in face, 0.375 in bore, which the formulas above reproduce; SDP/SI lists 48 DP gears from 14 to 108 teeth). Face widths and bores of stock gears vary by maker and series; those are not a standard.
  • Left out: the 25° pressure angle, stub and profile-shifted teeth, tolerances (AGMA quality numbers), backlash allowances, helical and bevel forms, and hub dimensions. Maker CAD: SDP/SI publishes inch-pitch spur gears with per-part CAD; linked, not copied.

Spur gears, 16 diametral pitch (DP): 12 to 60 teeth, 14.5° and 20°… size chart

teeth Npitch Ø = N / DP, in (mm)outside Ø = (N + 2) / DP, in (mm)root Ø 14.5°, in (mm)root Ø 20°, in (mm)base Ø 14.5°, in (mm)base Ø 20°, in (mm)example face, inexample bore, in
120.75 (19.05)0.875 (22.22)0.6054 (15.38)0.5938 (15.08)0.7261 (18.44)0.7048 (17.90)1/23/16
140.875 (22.22)1 (25.40)0.7304 (18.55)0.7188 (18.26)0.8471 (21.52)0.8222 (20.88)1/21/4
161 (25.40)1.125 (28.57)0.8554 (21.73)0.8438 (21.43)0.9681 (24.59)0.9397 (23.87)1/21/4
181.125 (28.57)1.25 (31.75)0.9804 (24.90)0.9688 (24.61)1.0892 (27.66)1.0572 (26.85)1/25/16
201.25 (31.75)1.375 (34.92)1.1054 (28.08)1.0938 (27.78)1.2102 (30.74)1.1746 (29.84)1/23/8
241.5 (38.10)1.625 (41.27)1.3554 (34.43)1.3438 (34.13)1.4522 (36.89)1.4095 (35.80)1/23/8
281.75 (44.45)1.875 (47.62)1.6054 (40.78)1.5938 (40.48)1.6943 (43.03)1.6445 (41.77)1/21/2
301.875 (47.62)2 (50.80)1.7304 (43.95)1.7188 (43.66)1.8153 (46.11)1.7619 (44.75)1/21/2
322 (50.80)2.125 (53.97)1.8554 (47.13)1.8438 (46.83)1.9363 (49.18)1.8794 (47.74)1/25/8
362.25 (57.15)2.375 (60.32)2.1054 (53.48)2.0938 (53.18)2.1783 (55.33)2.1143 (53.70)1/25/8
402.5 (63.50)2.625 (66.67)2.3554 (59.83)2.3438 (59.53)2.4204 (61.48)2.3492 (59.67)1/23/4
483 (76.20)3.125 (79.38)2.8554 (72.53)2.8438 (72.23)2.9044 (73.77)2.8191 (71.60)1/23/4
603.75 (95.25)3.875 (98.42)3.6054 (91.58)3.5938 (91.28)3.6306 (92.22)3.5238 (89.51)1/21

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
boreplain bore, example Ø per file (1/16 to 1 in, see the table)shaft of the same Øslidegear-*
centre distance(N1 + N2) / (2 × 16) in = 0.7937 (N1 + N2) mma second 16 DP gear of the same pressure angle (this family)designedgear-*
tooth form16 DP, 14.5° or 20° (the file name carries the angle); 14.5° and 20° gears do not mesh16 DP gear of the same pressure angledesignedgear-*

Where the files are

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

Martin Sprocket & GearG-85 spur gear data: PD = N / DP, OD = (N + 2) / DP, a = 1 / DP, ht = 2.157 / DP, t = 1.5708 / DPwebPublisher's page; dimensions are facts
Engineers EdgeGear design equations: 20 degree full-depth teeth (ANSI B6.1): PD, OD, a = 1/P, b = 1.25/P, ht = 2.25/P, centre distancewebPublisher's page; dimensions are facts
Machinery's Handbook, 31st ed. (online edition)Spur gearing: 14.5 degree full-depth tooth proportions (a = 1/P, b = 1.157/P, ht = 2.157/P)webPublisher's page; dimensions are facts
Machinery's Handbook, 31st ed. (online edition)Table 4: tooth proportions for fine-pitch involute spur and helical gears of 14.5, 20 and 25 degrees (ANSI B6.7): b = 1.2/P + 0.002, ht = 2.2/P + 0.002webPublisher's page; dimensions are facts
Machinery's Handbook, 31st ed. (online edition)Spur gearing: outside and root diameter formulas, 20 degree fine-pitch full-depth teeth (20 P and finer)webPublisher's page; dimensions are facts
Applied Industrial (Boston Gear)Boston Gear 16 DP 14.5 degree 14-tooth steel spur gear: PD 0.875 in, OD 1 in, face 0.5 in, bore 0.375 inwebPublisher's page; dimensions are facts
SDP/SI48 DP inch spur gears (catalogue pages list the tooth counts and bores; CAD per part on each product page)webPublisher's page; dimensions are facts
SDP/SIInch pitch spur gear catalogue sheetwebPublisher's page; dimensions are facts

Free files

★ Free files 26 parts. Generated by Xem Studio from the standard; threads are plain cylinders at major diameter. CC BY 4.0. index.json

gear-dp16-14-5pa-12t16 DP spur gear, 12 teeth, 14.5° pressure angle: pitch Ø19.050 mm (0.75 in), outside Ø22.225 mm (0.875 in), root Ø15.377 mm; face 12.70 mm (1/2 in) and bore Ø4.762 mm (3/16 in) are examples, the tooth form is the standard's; true involute flanks, no hub, keyway, chamfer or root filletSTEP · STL
gear-dp16-20pa-12t16 DP spur gear, 12 teeth, 20° pressure angle: pitch Ø19.050 mm (0.75 in), outside Ø22.225 mm (0.875 in), root Ø15.081 mm; face 12.70 mm (1/2 in) and bore Ø4.762 mm (3/16 in) are examples, the tooth form is the standard's; true involute flanks, no hub, keyway, chamfer or root filletSTEP · STL
gear-dp16-14-5pa-14t16 DP spur gear, 14 teeth, 14.5° pressure angle: pitch Ø22.225 mm (0.875 in), outside Ø25.400 mm (1 in), root Ø18.552 mm; face 12.70 mm (1/2 in) and bore Ø6.350 mm (1/4 in) are examples, the tooth form is the standard's; true involute flanks, no hub, keyway, chamfer or root filletSTEP · STL
gear-dp16-20pa-14t16 DP spur gear, 14 teeth, 20° pressure angle: pitch Ø22.225 mm (0.875 in), outside Ø25.400 mm (1 in), root Ø18.256 mm; face 12.70 mm (1/2 in) and bore Ø6.350 mm (1/4 in) are examples, the tooth form is the standard's; true involute flanks, no hub, keyway, chamfer or root filletSTEP · STL
gear-dp16-14-5pa-16t16 DP spur gear, 16 teeth, 14.5° pressure angle: pitch Ø25.400 mm (1 in), outside Ø28.575 mm (1.125 in), root Ø21.727 mm; face 12.70 mm (1/2 in) and bore Ø6.350 mm (1/4 in) are examples, the tooth form is the standard's; true involute flanks, no hub, keyway, chamfer or root filletSTEP · STL
gear-dp16-20pa-16t16 DP spur gear, 16 teeth, 20° pressure angle: pitch Ø25.400 mm (1 in), outside Ø28.575 mm (1.125 in), root Ø21.431 mm; face 12.70 mm (1/2 in) and bore Ø6.350 mm (1/4 in) are examples, the tooth form is the standard's; true involute flanks, no hub, keyway, chamfer or root filletSTEP · STL
gear-dp16-14-5pa-18t16 DP spur gear, 18 teeth, 14.5° pressure angle: pitch Ø28.575 mm (1.125 in), outside Ø31.750 mm (1.25 in), root Ø24.902 mm; face 12.70 mm (1/2 in) and bore Ø7.938 mm (5/16 in) are examples, the tooth form is the standard's; true involute flanks, no hub, keyway, chamfer or root filletSTEP · STL
gear-dp16-20pa-18t16 DP spur gear, 18 teeth, 20° pressure angle: pitch Ø28.575 mm (1.125 in), outside Ø31.750 mm (1.25 in), root Ø24.606 mm; face 12.70 mm (1/2 in) and bore Ø7.938 mm (5/16 in) are examples, the tooth form is the standard's; true involute flanks, no hub, keyway, chamfer or root filletSTEP · STL
gear-dp16-14-5pa-20t16 DP spur gear, 20 teeth, 14.5° pressure angle: pitch Ø31.750 mm (1.25 in), outside Ø34.925 mm (1.375 in), root Ø28.077 mm; face 12.70 mm (1/2 in) and bore Ø9.525 mm (3/8 in) are examples, the tooth form is the standard's; true involute flanks, no hub, keyway, chamfer or root filletSTEP · STL
gear-dp16-20pa-20t16 DP spur gear, 20 teeth, 20° pressure angle: pitch Ø31.750 mm (1.25 in), outside Ø34.925 mm (1.375 in), root Ø27.781 mm; face 12.70 mm (1/2 in) and bore Ø9.525 mm (3/8 in) are examples, the tooth form is the standard's; true involute flanks, no hub, keyway, chamfer or root filletSTEP · STL
gear-dp16-14-5pa-24t16 DP spur gear, 24 teeth, 14.5° pressure angle: pitch Ø38.100 mm (1.5 in), outside Ø41.275 mm (1.625 in), root Ø34.427 mm; face 12.70 mm (1/2 in) and bore Ø9.525 mm (3/8 in) are examples, the tooth form is the standard's; true involute flanks, no hub, keyway, chamfer or root filletSTEP · STL
gear-dp16-20pa-24t16 DP spur gear, 24 teeth, 20° pressure angle: pitch Ø38.100 mm (1.5 in), outside Ø41.275 mm (1.625 in), root Ø34.131 mm; face 12.70 mm (1/2 in) and bore Ø9.525 mm (3/8 in) are examples, the tooth form is the standard's; true involute flanks, no hub, keyway, chamfer or root filletSTEP · STL
gear-dp16-14-5pa-28t16 DP spur gear, 28 teeth, 14.5° pressure angle: pitch Ø44.450 mm (1.75 in), outside Ø47.625 mm (1.875 in), root Ø40.777 mm; face 12.70 mm (1/2 in) and bore Ø12.700 mm (1/2 in) are examples, the tooth form is the standard's; true involute flanks, no hub, keyway, chamfer or root filletSTEP · STL
gear-dp16-20pa-28t16 DP spur gear, 28 teeth, 20° pressure angle: pitch Ø44.450 mm (1.75 in), outside Ø47.625 mm (1.875 in), root Ø40.481 mm; face 12.70 mm (1/2 in) and bore Ø12.700 mm (1/2 in) are examples, the tooth form is the standard's; true involute flanks, no hub, keyway, chamfer or root filletSTEP · STL
gear-dp16-14-5pa-30t16 DP spur gear, 30 teeth, 14.5° pressure angle: pitch Ø47.625 mm (1.875 in), outside Ø50.800 mm (2 in), root Ø43.952 mm; face 12.70 mm (1/2 in) and bore Ø12.700 mm (1/2 in) are examples, the tooth form is the standard's; true involute flanks, no hub, keyway, chamfer or root filletSTEP · STL
gear-dp16-20pa-30t16 DP spur gear, 30 teeth, 20° pressure angle: pitch Ø47.625 mm (1.875 in), outside Ø50.800 mm (2 in), root Ø43.656 mm; face 12.70 mm (1/2 in) and bore Ø12.700 mm (1/2 in) are examples, the tooth form is the standard's; true involute flanks, no hub, keyway, chamfer or root filletSTEP · STL
gear-dp16-14-5pa-32t16 DP spur gear, 32 teeth, 14.5° pressure angle: pitch Ø50.800 mm (2 in), outside Ø53.975 mm (2.125 in), root Ø47.127 mm; face 12.70 mm (1/2 in) and bore Ø15.875 mm (5/8 in) are examples, the tooth form is the standard's; true involute flanks, no hub, keyway, chamfer or root filletSTEP · STL
gear-dp16-20pa-32t16 DP spur gear, 32 teeth, 20° pressure angle: pitch Ø50.800 mm (2 in), outside Ø53.975 mm (2.125 in), root Ø46.831 mm; face 12.70 mm (1/2 in) and bore Ø15.875 mm (5/8 in) are examples, the tooth form is the standard's; true involute flanks, no hub, keyway, chamfer or root filletSTEP · STL
gear-dp16-14-5pa-36t16 DP spur gear, 36 teeth, 14.5° pressure angle: pitch Ø57.150 mm (2.25 in), outside Ø60.325 mm (2.375 in), root Ø53.477 mm; face 12.70 mm (1/2 in) and bore Ø15.875 mm (5/8 in) are examples, the tooth form is the standard's; true involute flanks, no hub, keyway, chamfer or root filletSTEP · STL
gear-dp16-20pa-36t16 DP spur gear, 36 teeth, 20° pressure angle: pitch Ø57.150 mm (2.25 in), outside Ø60.325 mm (2.375 in), root Ø53.181 mm; face 12.70 mm (1/2 in) and bore Ø15.875 mm (5/8 in) are examples, the tooth form is the standard's; true involute flanks, no hub, keyway, chamfer or root filletSTEP · STL
gear-dp16-14-5pa-40t16 DP spur gear, 40 teeth, 14.5° pressure angle: pitch Ø63.500 mm (2.5 in), outside Ø66.675 mm (2.625 in), root Ø59.827 mm; face 12.70 mm (1/2 in) and bore Ø19.050 mm (3/4 in) are examples, the tooth form is the standard's; true involute flanks, no hub, keyway, chamfer or root filletSTEP · STL
gear-dp16-20pa-40t16 DP spur gear, 40 teeth, 20° pressure angle: pitch Ø63.500 mm (2.5 in), outside Ø66.675 mm (2.625 in), root Ø59.531 mm; face 12.70 mm (1/2 in) and bore Ø19.050 mm (3/4 in) are examples, the tooth form is the standard's; true involute flanks, no hub, keyway, chamfer or root filletSTEP · STL
gear-dp16-14-5pa-48t16 DP spur gear, 48 teeth, 14.5° pressure angle: pitch Ø76.200 mm (3 in), outside Ø79.375 mm (3.125 in), root Ø72.527 mm; face 12.70 mm (1/2 in) and bore Ø19.050 mm (3/4 in) are examples, the tooth form is the standard's; true involute flanks, no hub, keyway, chamfer or root filletSTEP · STL
gear-dp16-20pa-48t16 DP spur gear, 48 teeth, 20° pressure angle: pitch Ø76.200 mm (3 in), outside Ø79.375 mm (3.125 in), root Ø72.231 mm; face 12.70 mm (1/2 in) and bore Ø19.050 mm (3/4 in) are examples, the tooth form is the standard's; true involute flanks, no hub, keyway, chamfer or root filletSTEP · STL
gear-dp16-14-5pa-60t16 DP spur gear, 60 teeth, 14.5° pressure angle: pitch Ø95.250 mm (3.75 in), outside Ø98.425 mm (3.875 in), root Ø91.577 mm; face 12.70 mm (1/2 in) and bore Ø25.400 mm (1 in) are examples, the tooth form is the standard's; true involute flanks, no hub, keyway, chamfer or root filletSTEP · STL
gear-dp16-20pa-60t16 DP spur gear, 60 teeth, 20° pressure angle: pitch Ø95.250 mm (3.75 in), outside Ø98.425 mm (3.875 in), root Ø91.281 mm; face 12.70 mm (1/2 in) and bore Ø25.400 mm (1 in) are examples, the tooth form is the standard's; true involute flanks, no hub, keyway, chamfer or root filletSTEP · STL
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Plain text: sheet.txt · JSON: /api/geometry?object=spur-gears-dp-16

Spur gears, 16 diametral pitch (DP): 12 to 60 teeth, 14.5° and 20° involute, pitch / outside / root diameter and STEP/STL, isometric render of a generated part
Render of gear-dp16-20pa-28t from the free STEP; not to scale.

Fits with

Questions

What is the pitch diameter of a 16 DP, 20 tooth gear?

1.2500 in (31.750 mm); outside diameter 1.3750 in (34.925 mm).

What is the tooth depth of a 16 DP gear?

Whole depth 2.25 / 16 = 0.1406 in for 20°, 2.157 / 16 = 0.1348 in for 14.5° (minimum values).

What is the centre distance of two 16 DP gears, 20 and 40 teeth?

(20 + 40) / (2 × 16) = 1.8750 in (47.625 mm).