Gears and transmission
12T Spur Gear - Corrected Ø7.100 Root
- Bounding box
- 10.5 × 10.5 × 12.0 mm
- Engine
- Precision B-rep
- Parameters
- 11
- Published
- October 14, 2026
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The prompt
Correct the attached STEP gear. The actual minimum tooth-root diameter is approximately Ø6.586 mm, which is incorrect. Set the actual minimum radial distance of every tooth valley from the central gear axis to exactly 3.550 mm, giving a true root diameter of Ø7.100 mm. Ensure all 12 tooth valleys have the same minimum radius. Do not create inward-dipping spline curves below this radius. Preserve the Ø10.50 mm outside diameter, Ø9.00 mm pitch diameter, 12 teeth, 20° pressure angle, Ø9.00 mm hub, Ø5.00 mm axial bore, Ø2.25 mm transverse hole, 7.53 mm face width, 4.47 mm hub extension, and 12.00 mm overall length. Preserve the transverse hole position and its 0.10 mm clearance from the gear/hub shoulder. Export one valid watertight STEP solid in millimeters.
Parameters
| Name | Value | Range |
|---|---|---|
| Module | 0.75 mm | 0.2 – 3 |
| Number of Teeth | 12 teeth | 6 – 60 |
| Pressure Angle | 20 deg | 14.5 – 25 |
| Face Width | 7.53 mm | 1 – 40 |
| True Root Diameter | 7.1 mm | 3 – 30 |
| Hub Diameter | 9 mm | 3 – 30 |
| Hub Extension | 4.47 mm | 0.5 – 30 |
| Axial Bore Diameter | 5 mm | 1 – 20 |
| Transverse Hole Diameter | 2.25 mm | 0.5 – 6 |
| Transverse Hole Height (Z) | 8.76 mm | 4 – 20 |
| Transverse Hole Phase | 15 deg | 0 – 360 |
Every value above is a live dimension. Open a model like this in the editor and each one becomes a slider you can drag before exporting.
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