[family] speaker_pole_mount_socket

[BenchCAD]

Family: speaker_pole_mount_socket
Category: Audio/Visual Mounting & Rigging Hardware — cat:av-rigging (#3)
Anchor: Penn Elcom M1551 3" heavy-duty drawn-steel top hat for Ø35 mm / 1-3/8" poles — https://www.penn-elcom.com/us/3in-deep-heavy-duty-top-hat-for-1-3-8in-poles-m1551 (drawing: https://www.penn-elcom.com/media/catalog/product/M/1/M1551_m1551-he13lqm.jpg; hole-pattern dims from the M1553 series drawing: https://www.penn-elcom.com/media/catalog/product/M/1/M155360_m1553-60-dr16lqm.jpg)

Flanged drawn-steel cup ("top hat") screwed to the bottom panel of a PA speaker cabinet: a round flange with 4 clearance screw holes sits on the cabinet exterior; a closed-bottom cylindrical cup passes through a circular cutout and receives a Ø35 mm speaker-stand pole. Variants differ in cup depth, bore (35 vs 38.1), flange OD, and steel gauge.

Claim it: self-assign, then re-verify the evidence below before coding.
Done = one scoped PR (designs/speaker_pole_mount_socket/ only) that closes this issue.
Start here: AGENTS.md + docs/DESIGN_SPEC.md.

Reference images

Datasheet drawing	Part photo

Dimension table (manufacturer drawings unless noted; mm)

Model	Bore	Cup outer Ø	Flange OD	Cup depth L	Flange thk	Screw holes	Source
min depth Adam Hall SM701	35	—	110	58	—	—	retailer listing
Penn Elcom M1553/60	35	—	110	60	3	4 × Ø6.6	mfr drawing
Penn Elcom M1553/65	35	—	110	65	3	4 × Ø6.6	mfr drawing
Penn Elcom M1551 (anchor)	35	41	118	76	2.0 steel	4 (82.6 c-c, retailer)	mfr drawing + Parts Express
Penn Elcom M1553/95	35	—	110	95	3	4 × Ø6.6	mfr drawing
max Penn Elcom M1555	35	—	—	127	—	—	mfr tech table
(bore variant) M1552	38.1	—	—	76	—	4	mfr page

Parameters to verify at claim

• bore_d: 35 mm (38.1 on M1552); cup_outer_d: 41 at bore 35 (M1551)
• flange_od: 110–118 mm; flange_t: 2.0–3.0 mm
• depth: 58–127 mm; n_holes = 4; hole_d = 6.6 mm (M1553 drawing; M1551's unpublished)
• installation: cutout 50.8 mm, hole span 82.6 mm c-c (Parts Express text, M1551 only)

Engineering constraints

• pole clearance: cup ID ≈ bore + ~2 mm diametral clearance (M1551: outer Ø41 in 2.0 mm steel → ID ≈ 37 over a Ø35 pole)
• sandwich ordering: cup outer Ø (41) < cabinet cutout (50.8) < screw-hole span (82.6) < flange OD (110–118)
• closed (domed) cup bottom — pole bottoms out at depth L; L < cabinet internal height
• Ø6.6 holes clear M6/[family] round_duct_butterfly_damper: round HVAC balancing damper #12 screws, equally spaced, concentric with bore

Caveats: Adam Hall 87005 (wanted-list anchor) unverifiable — site bot-walled, part number unknown at retailers; SM700/SM701 data is retailer-transcribed. Penn Elcom serves M1551's image for M1552's "drawing" (md5-identical) — M1552 geometry is a gap. Hole span "across" is ambiguous (likely BCD ≈ 82.6).

[github-actions]

✅ Registry check: speaker_pole_mount_socket collides with none of the 0 known names.

Thanks for the proposal! Whoever claims this verifies it first — the
5-minute evidence check in CONTRIBUTING.md ("Claiming an issue = you verify it"):
standard link real · dimensioned drawing · table with min/max rows · two numbers spot-checked.

Gaps? Fill them yourself (credited) or label needs-evidence with one comment naming what's missing.

新人中文指南: GETTING_STARTED.zh.md · Questions → Discord