Helical Gear Shell LED Lamp Shade - 42mm E27 Fitter

Helical Gear Shell LED Lamp Shade - 42mm E27 Fitter

LED-only untested prototype. No incandescent or halogen. Not printed, fitted, heat-tested or load-tested. Use an existing certified shade-ring holder. Measure your hardware, keep plastic clear of bulb and wiring, and check manufacturer limits. No electrical parts included. Not a working transmission gear.

24 raised helical tooth-like ribs on a 128mm drum. Overall envelope 136.05 x 130 x 136.05mm, Y-up in the original STL. Orient the open lower rim onto the slicer bed. Nominal 1.6mm drum wall, 45deg total twist over 90mm rib height, 4mm crest and 6mm root width.

Nominal 42mm bore targets E27/ES shade-ring holders. Native 32-facet revolve makes the across-flat bore about 41.80mm before print tolerances. Plain 50mm OD cylindrical neck. Existing retaining ring screws onto the holder inside the bore and clamps the top annular neck rim at Y=130; the 60mm lower shoulder reinforces the transition, but is not the clamping seat. A 56mm-OD ring covers the top rim. E27 bulb size alone does not establish shade-fit compatibility. Measure barrel, ring and threaded length; print a fitter-only sample first.

Native STL: 310,944 triangles, 25 overlapping components, 84 near-zero-area triangles. All mesh edges paired after vertex welding, but the parts are not Boolean-fused. Merge overlapping volumes and repair/check every layer in your slicer. Raw native export, no external geometry generation or mesh repair.

Article: https://blog.truegeometry.com/0_0_0_0/blogs/post-30d8f3e8.html

Original design; AI-assisted. CC BY 4.0.

FULL NATIVE PLAYGROUND RECIPE

HELICAL GEAR SHELL LED SHADE - native TrueGeometry Playground recipe

Dimensions mm. 42mm fitter bore, 50mm OD cylindrical neck, 60mm transition shoulder.

Retaining ring clamps the top annular neck rim, not the lower shoulder.

128mm drum, 136mm tooth envelope, 130mm height, 24 raised teeth with 45deg twist.

LED only, untested prototype, no incandescent or halogen. Measure your holder and retaining rings before use. Not a working transmission gear.

No booleans. Overlapping solids must be merged in the slicer.

STAGE A: Script panel on an empty scene.

/unit mm

/parametric sketch_composite [{"type":"line","x":64,"y":0},{"type":"line","x":64,"y":94},{"type":"line","x":32,"y":123},{"type":"line","x":30,"y":123},{"type":"line","x":30,"y":126},{"type":"line","x":25,"y":126},{"type":"line","x":25,"y":130},{"type":"line","x":21,"y":130},{"type":"line","x":21,"y":123},{"type":"line","x":30.4,"y":121.4},{"type":"line","x":62.4,"y":93.3},{"type":"line","x":62.4,"y":0},{"type":"line","x":64,"y":0}]

/tag_last BodyProfile

/3d_curve equation "0" "t" "0" 0 150 2

/tag_last Axis

/revolve @BodyProfile @Axis 360

/tag_last DrumShell

/delete @BodyProfile

/delete @Axis

/setprop @DrumShell color #c7e6ee

/parametric sketch_composite [{"type":"line","x":63.4,"y":-3},{"type":"line","x":68,"y":-2},{"type":"line","x":68,"y":2},{"type":"line","x":63.4,"y":3},{"type":"line","x":63.4,"y":-3}]

/tag_last ToothLower

/rotate @ToothLower 90 0 0

/move @ToothLower 0 2 0

/duplicate @ToothLower

/tag_last ToothUpper

/move @ToothUpper 0 90 0

/3d_curve equation "0" "t" "0" 2 92 90

/tag_last ToothSpine

STAGE B: Submit separately in chat and wait for success.

/sweep_variable @ToothLower @ToothUpper @ToothSpine solid twist:45

STAGE C: Script panel.

/tag_last HelixTooth

/delete @ToothLower

/delete @ToothUpper

/delete @ToothSpine

/pattern @HelixTooth circ 24 360 y

/group_visible HelicalGearShade

/setprop @HelicalGearShade color #c7e6ee

/setprop @HelicalGearShade roughness 0.65

/origin

/view iso

/view fit

STAGE D: Export in chat.

/export_stl @HelicalGearShade

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