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S shapes (AISC American Standard beams): S6x12.5, S12x31.8 dimensions + STEP/STL

What are the dimensions of an S6x12.5 beam? · Standard part · basis: AISC Shapes Database (v15.0 values): d, bf, tw, tf, k for every S shape; 2:12 inner flange slope

Also called: s6x12.5 dimensions, s6x12.5, s 6 x 12.5, s12x31.8, s3x5.7, s4x7.7, s8x23, s10x25.4, s15x42.9, s20x66, american standard beam dimensions, s beam dimensions, i beam dimensions, s shape step file, tapered flange i beam

Exact dimensions. True size, with no printing tolerance added.

length
101.6 mm

Notes

  • S shapes are the American Standard beams: narrower flanges than a W of the same depth, and flanges whose inner faces slope about 17 % (2 in 12 in). S12x31.8 means about 12 in deep and 31.8 lb per foot.
  • The tabulated flange thickness tf of a tapered flange is the mean thickness. The files draw the 2:12 slope (the figure is quoted on draftsperson.net, no AISC page was readable here) with tf at the middle of the flange projection, so the tip is thinner and the root thicker than tf.
  • Root radius is derived from the printed k (outside face of the flange to the web toe of the fillet) with the sloped flange: r = (k - root thickness) x tan((90 + slope angle)/2). Tips are square (no toe radius is printed).
  • Files are 4 in (101.6 mm) long extrusions along X; the section is in the YZ plane, centred on y = 0, with z = 0 on the bottom face.
  • 15 of the 28 S sizes have files; all are in the table. Drawn area is within 3 % of the printed area on all of them.

S shapes (AISC American Standard beams): S6x12.5, S12x31.8… size chart

shapelb/ftd (in)bf (in)tw (in)tf mean (in)k (in)d (mm)bf (mm)tw (mm)tf (mm)
S24x121121.024.58.050.81.092.0622.3204.520.3227.69
S24x106106.024.57.870.621.092.0622.3199.915.7527.69
S24x100100.024.07.250.7450.871.75609.6184.118.9222.1
S24x9090.024.07.130.6250.871.75609.6181.115.8822.1
S24x8080.024.07.00.50.871.75609.6177.812.722.1
S20x9696.020.37.20.80.921.75515.6182.920.3223.37
S20x8686.020.37.060.660.921.75515.6179.316.7623.37
S20x7575.020.06.390.6350.7951.63508.0162.316.1320.19
S20x6666.020.06.260.5050.7951.63508.0159.012.8320.19
S18x7070.018.06.250.7110.6911.5457.2158.818.0617.55
S18x54.754.718.06.00.4610.6911.5457.2152.411.7117.55
S15x5050.015.05.640.550.6221.38381.0143.313.9715.8
S15x42.942.915.05.50.4110.6221.38381.0139.710.4415.8
S12x5050.012.05.480.6870.6591.44304.8139.217.4516.74
S12x40.840.812.05.250.4620.6591.44304.8133.311.7316.74
S12x3535.012.05.080.4280.5441.19304.8129.010.8713.82
S12x31.831.812.05.00.350.5441.19304.8127.08.8913.82
S10x3535.010.04.940.5940.4911.13254.0125.515.0912.47
S10x25.425.410.04.660.3110.4911.13254.0118.47.912.47
S8x2323.08.04.170.4410.4251.0203.2105.911.210.79
S8x18.418.48.04.00.2710.4251.0203.2101.66.8810.79
S6x17.2517.256.03.570.4650.3590.813152.490.711.819.12
S6x12.512.56.03.330.2320.3590.813152.484.65.899.12
S5x1010.05.03.00.2140.3260.75127.076.25.448.28
S4x9.59.54.02.80.3260.2930.75101.671.18.287.44
S4x7.77.74.02.660.1930.2930.75101.667.64.97.44
S3x7.57.53.02.510.3490.260.62576.263.88.866.6
S3x5.75.73.02.330.170.260.62576.259.24.326.6

Where the files are

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

AISC (values via the ambaker1/aisc-csv extract, MIT)AISC Shapes Database v15.0 (W, S, C, MC, L, HSS): d, bf, tw, tf, k, t, HSS Ht, B, OD, tnom, tdes, A, weightwebAISC publishes the database free of charge; dimensions are facts. aisc.org itself was not reachable from the build box
AISCShapes Database (free download, v16.0 on aisc.org) - the values here are the v15.0 release; check the current release before relying on a sizewebPublisher's page; dimensions are facts
draftsperson.netSteel shapes and sizes: American Standard beams (S) and channels (C) have a slope of approximately 17 percent (2 in 12 in) on the inner flange surfaceswebPublisher's page; dimensions are facts

Free files

★ Free files 15 parts. Generated by Xem Studio from the standard; threads are plain cylinders at major diameter. CC BY 4.0. index.json

s3x5-7-4inS3 x 5.7 S shape: depth 3.0 in (76.2 mm), flange 2.33 in (59.2 mm), web 0.17 in, mean flange 0.26 in, flanges sloped 2 in 12 in inside, 4 in longSTEP · STL
s4x7-7-4inS4 x 7.7 S shape: depth 4.0 in (101.6 mm), flange 2.66 in (67.6 mm), web 0.193 in, mean flange 0.293 in, flanges sloped 2 in 12 in inside, 4 in longSTEP · STL
s5x10-4inS5 x 10 S shape: depth 5.0 in (127.0 mm), flange 3.0 in (76.2 mm), web 0.214 in, mean flange 0.326 in, flanges sloped 2 in 12 in inside, 4 in longSTEP · STL
s6x12-5-4inS6 x 12.5 S shape: depth 6.0 in (152.4 mm), flange 3.33 in (84.6 mm), web 0.232 in, mean flange 0.359 in, flanges sloped 2 in 12 in inside, 4 in longSTEP · STL
s6x17-25-4inS6 x 17.25 S shape: depth 6.0 in (152.4 mm), flange 3.57 in (90.7 mm), web 0.465 in, mean flange 0.359 in, flanges sloped 2 in 12 in inside, 4 in longSTEP · STL
s8x18-4-4inS8 x 18.4 S shape: depth 8.0 in (203.2 mm), flange 4.0 in (101.6 mm), web 0.271 in, mean flange 0.425 in, flanges sloped 2 in 12 in inside, 4 in longSTEP · STL
s8x23-4inS8 x 23 S shape: depth 8.0 in (203.2 mm), flange 4.17 in (105.9 mm), web 0.441 in, mean flange 0.425 in, flanges sloped 2 in 12 in inside, 4 in longSTEP · STL
s10x25-4-4inS10 x 25.4 S shape: depth 10.0 in (254.0 mm), flange 4.66 in (118.4 mm), web 0.311 in, mean flange 0.491 in, flanges sloped 2 in 12 in inside, 4 in longSTEP · STL
s10x35-4inS10 x 35 S shape: depth 10.0 in (254.0 mm), flange 4.94 in (125.5 mm), web 0.594 in, mean flange 0.491 in, flanges sloped 2 in 12 in inside, 4 in longSTEP · STL
s12x31-8-4inS12 x 31.8 S shape: depth 12.0 in (304.8 mm), flange 5.0 in (127.0 mm), web 0.35 in, mean flange 0.544 in, flanges sloped 2 in 12 in inside, 4 in longSTEP · STL
s12x50-4inS12 x 50 S shape: depth 12.0 in (304.8 mm), flange 5.48 in (139.2 mm), web 0.687 in, mean flange 0.659 in, flanges sloped 2 in 12 in inside, 4 in longSTEP · STL
s15x42-9-4inS15 x 42.9 S shape: depth 15.0 in (381.0 mm), flange 5.5 in (139.7 mm), web 0.411 in, mean flange 0.622 in, flanges sloped 2 in 12 in inside, 4 in longSTEP · STL
s18x54-7-4inS18 x 54.7 S shape: depth 18.0 in (457.2 mm), flange 6.0 in (152.4 mm), web 0.461 in, mean flange 0.691 in, flanges sloped 2 in 12 in inside, 4 in longSTEP · STL
s20x66-4inS20 x 66 S shape: depth 20.0 in (508.0 mm), flange 6.26 in (159.0 mm), web 0.505 in, mean flange 0.795 in, flanges sloped 2 in 12 in inside, 4 in longSTEP · STL
s24x80-4inS24 x 80 S shape: depth 24.0 in (609.6 mm), flange 7.0 in (177.8 mm), web 0.5 in, mean flange 0.87 in, flanges sloped 2 in 12 in inside, 4 in longSTEP · STL
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Plain text: sheet.txt · JSON: /api/geometry?object=aisc-s-shapes

S shapes (AISC American Standard beams): S6x12.5, S12x31.8 dimensions + STEP/STL, isometric render of a generated part
Render of s10x25-4-4in from the free STEP; not to scale.

Fits with

W shapes (AISC wide-flange beams): W8x10, W12x26, W14x90 dimensions + STEP/STL, isometric render of a generated part
W shapes (AISC wide-flange beams): W8x10, W12x26, W14x90 dimensions + STEP/STL101.6 mm★ 48 files
C channels (AISC American Standard channels): C6x13, C8x11.5, C12x20.7 dimensions + STEP/STL, isometric render of a generated part
C channels (AISC American Standard channels): C6x13, C8x11.5, C12x20.7 dimensions + STEP/STL101.6 mm★ 19 files
MC channels (AISC miscellaneous channels): MC6x12, MC8x8.5, MC12x31 dimensions + STEP/STL, isometric render of a generated part
MC channels (AISC miscellaneous channels): MC6x12, MC8x8.5, MC12x31 dimensions + STEP/STL101.6 mm★ 12 files
Steel angles L (AISC): L4x4x1/4, L3x3x1/4, L2x2x1/4, L5x3x1/4 dimensions + STEP/STL, isometric render of a generated part
Steel angles L (AISC): L4x4x1/4, L3x3x1/4, L2x2x1/4, L5x3x1/4 dimensions + STEP/STL101.6 mm★ 31 files

Questions

What is an S shape?

An American Standard beam: tapered inner flange faces (2 in 12 in) and narrower flanges than a W shape.

What does S6x12.5 mean?

About 6 in deep, 12.5 lb per foot.