⚠️ Assembly Safety

Essential safety practices: Always wear eye protection when drilling or using power tools. Never assemble with batteries connected - remove all power sources during mechanical assembly. Work in a clean, well-lit area. Never force parts - if something doesn't fit, check alignment and tolerances.

Assembly Process

Follow this sequence to ensure proper fit and avoid having to disassemble completed sections.

  1. 1

    Chassis Preparation

    Test-fit all chassis components before final assembly. Check for proper clearances around motors, electronics, and moving parts.

    Tip: Sand, file, or dremel any tight-fitting areas identified during test assembly. It's much easier to adjust parts before they're permanently fastened. Afterwards, fix the issues in CAD for the final print.
  2. 2

    Motor Installation

    Drive motors should easily slide into their respective mounts. If you are using the mounting screws, apply loctite to prevent the screws from backing out.

    Press-fit technique: Use 0.2mm as a general rule of thumb for tolerancing.
  3. 3

    Electronics Installation

    With motors installed, route motor wires and mount speed controllers, receivers, and other electronics with proper wire management.

    Complete all the wiring at this step: The prototype chassis should serve as a guide for wire management, and you can make dimension changes / final tolerance edits as you approach the final product.
  4. 4

    Wheel Hub & Shaft Collar Assembly

    Slide shaft collars onto wheel hubs, then install the assembly onto the shafts. The long setscrew interlocks with the hub and shaft, preventing wheel slippage during fights.

    Shaft collar placement: Make a hole in the wheel, allows you to screw in the setscrew after the hub + shaft collar is already on the shaft. Apply locite onto the set screws if nessessary.
  5. 5

    Final Chassis Assembly

    Install top plate(s) and any separate upright components to complete the chassis structure.

    Top plate installation: If you are using plastite screws, do not overtighten them, or they will damage the printed part.
[Assembly sequence photos - chassis preparation through final assembly]

Motor Mounting & Retention

Different motor types require different mounting approaches for reliable operation throughout competition.

Drive Motor Mounting

  • Screw mounting: Most drive motors mount with screws through gearbox - make sure to loctite!
  • Motor brackets: Use printed braces that physicaly constrain the motor
  • Alignment: Check that wheels are parallel and motors don't bind
  • Clearance: Ensure adequate space for wiring and maintenance access

Weapon Motor Press-Fit (Spinners)

  • Hole tolerance: 0.1-0.2mm larger than motor diameter for a light press-fit
  • Installation force: Use steady, controlled pressure - vice, arbor press, clamp
  • Support structure: Ensure adequate wall thickness (6mm recomended) around motor mounts
  • Alignment check: Verify motor shaft is perpendicular to mounting surface

Wheel Hub & Shaft Collar System

  • Hub design: Include D-shaft bore to properly interface with the drive motor's D-shaft
  • Collar placement: Position to compress against shaft flats
  • Set screw technique: Use thread locker and tighten against shaft flat
  • Backup retention: Consider loctite for high load drive applications
[Motor mounting and shaft collar installation photos]

Fasteners for 3D Printed Parts

Choose the right fastener type and technique for reliable assembly of plastic components.

Plastite Screws (Recommended)

Thread-forming design: Creates strong threads in plastic without removing material
Common sizes: M3 and no.4 plastites, 3/8" in length for most combat robot applications
Hole Size: Use drill sizes specified by manufacturer for optimal thread engagement. (Recomended 2.4mm diameter for no.4 plastites)

Heat-Set Inserts

Best for: Frequently disassembled joints
Installation: Use soldering iron at 340-830°F, insert slowly and evenly
Thread sizes: M3 is most common for plastic antweights

Machine Screws with Nuts

Through-bolted joints: Maximum strength for critical structural connections
thread size: M3 is most common for plastic antweights
Thread locker: Use on nuts to prevent loosening from vibration
[Fastener types and installation examples]

Pre-Test Assembly Checklist

Complete this checklist before powering up your robot for the first time.

  • All fasteners properly tightened and secured
  • Motors properly seated in mounts with no binding
  • Wheel hubs securely attached with shaft collars
  • No interference between moving parts and chassis
  • Electronics securely mounted and protected
  • All wiring properly routed and protected from moving parts
  • Battery compartment accessible and secure
  • Weapon (if applicable) properly balanced and secured
  • All screws and fasteners accounted for - none loose in chassis
  • Weight within 1 pound