Library › Hardware › S shapes (AISC American Standard beams): S6x12.5, S12x31.8…

S12 x 31.8 S shape

S12 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 long

Exact dimensions. True size, no printing tolerance added. Threads are plain cylinders at the major diameter.

STEP STL free, CC BY 4.0 (credit "Xem Studio")

Dimensions

shapeS12x31.8
lb/ft31.8
d (in)12.0
bf (in)5.0
tw (in)0.35
tf mean (in)0.544
k (in)1.19
d (mm)304.8
bf (mm)127.0
tw (mm)8.89
tf (mm)13.82
Let your AI pull this. Add https://xemstudio.com/mcp to Claude, ChatGPT, Cursor or any MCP client (free, no account, one minute) and it can look up exact sizes, mating fits and free STEP/STL from every chat.
Set it up →

From the full sheet

S shapes (AISC American Standard beams): S6x12.5, S12x31.8 dimensions + STEP/STL: every size, notes, mating features and sources. What are the dimensions of an S6x12.5 beam?

Other sizes