Gears
RazorCAD's Gears tool on the Sketch tab draws involute gear trains as closed profiles, ready to extrude.
Creating a gear train
- Draw lines between the gear centres (centerlines work well).
- Select the lines (or a single point for one gear) and click Gears. If you are not in a sketch, RazorCAD opens the selected sketch (or starts one) and asks you to click the centre lines, then press Enter or Make Gears.
- Each line end point becomes a gear. Neighbouring gears mesh along the line, and teeth are turned automatically so they mesh.
- Extrude the sketch: each gear becomes its own body.
Gear numbers are shown on the gears in the sketch (view labels only, not geometry).
The Gear Train panel
Click a gear to open it.
| Setting | Meaning |
|---|---|
| Module and pressure angle | The tooth size and shape for the whole train |
| Teeth per gear, or ratio per mesh | Setting a ratio sets the next gear's teeth. Changing teeth or a ratio changes the centre-line lengths to suit, including your own length dimensions on those lines. |
| Backlash, tip/root clearance | Tolerances for prototyping and 3D printing |
| Bore diameter | The centre hole |
| Turn | Rotates the first gear |
| Set the line lengths to the mesh distance | Adds driving dimensions so the gears mesh exactly; each mesh shows ✔ or how far off it is |
Rules for a valid train
Centres must be exactly at the mesh distance, gears must not overlap and each gear needs at least 6 teeth. Fixed line lengths get a module and teeth that fit. Edits that would break a train are refused. A broken train is drawn red with a Fit gears to the lines button and can't be extruded.