Gears and transmission
Spur Gear with Corrected Root Diameter
- Bounding box
- 10.3 × 10.3 × 12.0 mm
- Engine
- Precision B-rep
- Parameters
- 10
- Published
- October 14, 2026
Download
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The prompt
Modify the attached STEP gear model. **Correct ONLY the tooth-root diameter.** The current actual root diameter is Ø7.134448 mm, but the required root diameter is exactly Ø7.100000 mm. Required correction: - Current root radius: 3.567224 mm - Target root radius: 3.550000 mm - Radial reduction: 0.017224 mm Modify all 12 tooth valleys uniformly so that the actual minimum radius of each valley is exactly 3.550000 mm, measured from the central gear axis. IMPORTANT: 1. Modify the physical tooth-root geometry, not just a parameter. 2. Do not regenerate or redesign the entire gear. 3. Preserve the existing tooth flanks, tooth tips, and tooth spacing. 4. Maintain smooth transitions between the tooth flanks and corrected root surfaces. 5. Do not allow any tooth valley to extend below the 3.550000 mm radius. **Preserve all other dimensions exactly:** - 12 teeth - Outside diameter: Ø10.500 mm - Pitch diameter: Ø9.000 mm - Module: 0.75 mm - Pressure angle: 20° - Gear face width: 7.530 mm - Hub diameter: Ø9.000 mm - Hub extension: 4.470 mm - Overall length: 12.000 mm - Axial through-bore: Ø5.000 mm - Transverse through-hole: Ø2.300 mm - Transverse hole center: Z = 8.780 mm - Nominal shoulder-to-hole-edge clearance: 0.100 mm - Transverse hole aligned beneath two opposite tooth valleys **Validation requirements:** - Verify the actual minimum root radius at several axial cross-sections. - Confirm all 12 valleys have a minimum radius of 3.550000 mm. - Confirm the transverse hole remains Ø2.300 mm. - Produce one valid, watertight solid. - Export the corrected model as a STEP file in millimeters. Do not alter any other geometry.
Parameters
| Name | Value | Range |
|---|---|---|
| Module | 0.75 mm | 0.1 – 3 |
| Number of Teeth | 12 mm | 3 – 40 |
| Gear Face Width | 7.53 mm | 2 – 50 |
| Root Diameter | 7.1 mm | 6 – 8 |
| Hub Diameter | 9 mm | 6 – 15 |
| Hub Length | 4.47 mm | 1 – 20 |
| Axial Bore Diameter | 5 mm | 2 – 8 |
| Transverse Hole Diameter | 2.3 mm | 1 – 5 |
| Transverse Hole Center Z | 8.78 mm | 5 – 12 |
| Shoulder to Hole Edge Clearance | 0.1 mm | 0.05 – 0.5 |
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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