Starting 3D renderer…
Choose a generator, enter actual dimensions in millimetres, inspect the interactive 3D mesh, then export a model for your slicer or CAD. STL and OBJ contain raw triangulated surfaces; GLB includes rendering materials. Save JSON to reopen the parameters and assembly.
Spur gear: generated from sampled involute flanks using metric module, pressure angle, standard 1.0m addendum and 1.25m dedendum. Root transitions are simplified radial/root-arc connections, not true hobbed trochoids. Teeth below the no-undercut threshold are flagged. Pairs must share module and pressure angle. Backlash reduces tooth thickness at the pitch circle; it does not replace testing.
Servo horns and splines: generic bolt-hole geometry is dimensioned. 21T/25T splines are experimental profile approximations because true spline geometry varies across manufacturers; first print a test coupon and measure the actual output shaft before loading a mechanism.
Legacy concepts: the tapered bevel gear, differential carrier blank and straight-sided simple wheel are kept for exploratory use, not represented as mechanically compatible transmission components.
LEGO/Technic-style parts: dimensions are parametric approximations for personal prototypes, not certified compatible components. Slotted friction connectors, bevel teeth and differentials require special mechanical design and are not presented as finished mechanisms.
| Model | Geometric basis | Notes |
|---|---|---|
| Spur gear | Pitch Ø=m×z, outer Ø=m(z+2), root Ø=m(z−2.5), base Ø=m z cos(α) | Involute sampled tooth flanks, approximate root transition |
| Gear pair | Centre distance m(z₁+z₂)/2 | Matches at chosen m, α; clearance offset optional |
| Rack | Tooth pitch πm, flank slope tan(α) | Standard basic rack profile |
| D-shaft socket | Circle with specified flat depth | Measure actual shaft flat-to-round dimension |
| Pivot hole | Nominal dowel Ø + configured allowance | Test rotation versus press-fit |
Sources for dimensional relationships: involute gearing formulas, Three.js STL exporter documentation.
Design parametric gears, shafts, pivots, and robot parts in 3D; build assemblies and export STL, OBJ, GLB, SVG, or JSON projects.
Mechanical Parts Studio generates editable 3D geometry from configurable dimensions, shows the part in an orbitable preview, and provides basic mesh diagnostics. It includes gear and rack models, shafts and couplers, pivots and bearings, servo parts, structural components, and demonstration assemblies.
Use it to explore dimensions, create a starting geometry for CAD or a slicer, compare part proportions, and assemble a preview of several components. It is a browser-based design aid, not a substitute for engineering review or a full CAD package.
Inputs depend on the selected generator and may include tooth count, module, pressure angle, backlash, bore size, shaft profile, lengths, hole spacing, clearances, colour, and fit compensation. The tool uses millimetres for its dimensional controls.
Export the active model as binary STL, OBJ, or GLB. STL follows the millimetre convention but does not contain unit metadata; GLB retains preview material colour. SVG export is available only for parts with a supported planar profile. Project JSON stores the selected parameters and assembly geometry so it can be reopened in this app. The assembly workspace is limited to 36 solid objects.
Some generators are marked Prototype or Concept. Gear tooth root transitions are simplified; the bevel gear, differential carrier blank, and straight-sided wheel are exploratory concepts rather than verified functional mechanisms. Technic-style dimensions are approximations, and 21T/25T servo spline profiles are experimental approximations. Check the selected part’s on-screen notes and mesh diagnostics.
Printer tolerances and material shrinkage vary. Make test coupons, inspect the exported model in CAD or a slicer, and validate strength, fit, motion, and print orientation before use. Do not rely on these prototypes for safety-critical, high-speed, or high-torque applications.
The app does not automatically save projects or sync them to an account. Your current work remains in the open browser page until you export it; use Project JSON to save and Open JSON to restore it. Three.js is loaded from a public CDN, so an internet connection is needed to load the 3D editor. This page uses the site’s standard Google Analytics tag; the app does not send part parameters or project geometry in analytics events.
No. Export a Project JSON file to preserve the current parameters and assembly, then open that JSON file later to restore them.
Exports are geometry starting points. Inspect them in your CAD or slicing software and test clearances, fit, strength, and printer tolerances before relying on a part.
The active part or assembly can be exported as STL, OBJ, or GLB. SVG is available for supported planar profiles, and Project JSON saves parameters and assembly data for reopening in this app.
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