Library › Everyday mounts › Camera tripod thread bosses: 1/4-20 UNC and 3/8-16 UNC

1/4-20 UNC boss

1/4-20 UNC boss: Ø16 × 10 (my size), blind core hole Ø5.35 × 8 deep from the top face for the 1/4-20 UNC internal thread (major Ø6.35)

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

thread	1/4-20 UNC
major Ø (mm)	6.35
core hole Ø (mm)	5.35
boss (my design)	Ø16 × 10, hole 8 deep
from	DIN 4503-1 / ISO 1222 (Threading Tools Guide)

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From the full sheet

Camera tripod thread bosses: 1/4-20 UNC and 3/8-16 UNC: every size, notes, mating features and sources. What thread is a camera tripod screw?

Other sizes

3/8-16 UNC boss