Design a hobbygrade car with two gear mechanism

# Upwork Job Post — SCY RC --- ## TITLE (pick one) **Option 1 (recommended):** `Mechanical Engineer / CAD Designer — RC Vehicle 2-Speed Gearbox & Adjustable Suspension (1/10 Scale)` **Option 2 (broader reach):** `CAD Designer Needed — RC Car Gearbox + Suspension Design (Spec & Calculations Provided)` --- ## CATEGORY Engineering & Architecture → Mechanical Engineering / CAD ## SKILLS TO TAG `SolidWorks` · `Fusion 360` · `Mechanical Design` · `CAD` · `Product Design` · `3D Modeling` · `Design for Manufacturing` · `Gear Design` --- ## JOB DESCRIPTION (copy below this line) **Project overview** I'm developing a 1/10 scale 4WD RC vehicle that switches between two driving modes — rock crawler and high-speed buggy — using the same chassis, motor, and drivetrain. I have a complete engineering specification with calculated gear ratios, tooth counts, and performance figures already validated. I need a CAD designer to turn this specification into manufacturable 3D models and drawings. **What already exists** - Full written engineering specification (~25 sections) - Verified gear calculations: two gear pairs sharing a 36.00 mm center distance (12T:60T and 27T:45T, module 1.0), plus a fixed 3.82:1 primary stage - Target performance figures, material specs, tolerances, and BOM - Layout sketches and concept renders **What I need from you** **Phase 1 — 2-speed gearbox (this contract)** 1. Parametric 3D model of the 2-speed gearbox: housing, shafts, gears, sliding dog collar, shift fork 2. Correct involute tooth profiles generated from the supplied module and tooth counts 3. Interference and clearance check across both gear positions 4. 2D manufacturing drawings with tolerances and GD&T 5. STEP files suitable for sending to a machine shop **Phase 2 — possible follow-on work (separate contract)** Adjustable suspension assembly with a 3-position shock tower and a cam-operated ride-height mechanism. **Requirements** - SolidWorks or Fusion 360 - Demonstrable gear and gearbox design experience — please show relevant examples - Comfortable working to metric specs and producing drawings a machine shop can quote from - Design-for-manufacturing awareness (CNC prototype now, die-cast later) **Nice to have** - RC vehicle or small-mechanism experience - FEA capability for gear tooth stress verification **To apply, please include** 1. Two or three examples of gearbox or mechanism CAD work you've done 2. Your estimate of hours for Phase 1 3. Which software you'd use and what file formats you'd deliver 4. One question about the project — I'd rather work with someone who reads the spec carefully I'll share the full specification document with shortlisted applicants. **Budget:** Fixed price, open to proposals. Please quote Phase 1 only. **Timeline:** Flexible — quality matters more than speed. --- ## NOTES FOR YOU (do not post this section) **Why Phase 1 only:** scoping to just the gearbox keeps the first contract small and lets you evaluate the designer before committing to the whole vehicle. If they're good, extend. If not, you've lost one contract's worth, not the whole project. **On budget:** leaving it open invites a wide range. If you'd rather filter early, a stated range works better than "open to proposals." Gearbox CAD from an existing spec typically runs a wide range depending on the designer's region and experience level — get 5+ proposals before judging what's reasonable for your scope. **Red flags in applicants:** anyone who quotes without asking a single question, anyone whose portfolio is all rendering and no drawings, anyone promising a very short turnaround. Drawings with tolerances are the actual deliverable — pretty renders are not. **Protect your IP:** the cam-lever suspension mechanism is your differentiator. Consider keeping it out of Phase 1 entirely, and use an NDA before sharing that portion of the spec.