Geared Pan-Tilt Laser Pointer Mount

A robust, 3D-printable pan-tilt mechanism designed around standard hobby servos, smooth-running ball bearings, and a 20mm diameter laser pointer module. This design utilizes a precision herringbone gear drive system to maximize torque, reduce backlash, and ensure self-centering gear alignment.

To isolate radial loads from the servo shafts and ensure smooth operation, two 624 ball bearings are pressed directly into the hubs of the two herringbone gears.

Technical Specifications & Features

• Drive System: Self-centering Herringbone Gears (prevents axial thrust and minimizes backlash).
• Pan Range: Driven by 1x Winch Hobby Servo (continuous or high-range panning).
• Tilt Range: Driven by 1x 90-Degree Hobby Servo (~90° mechanical clearance).
• Optic Compatibility: Fits a standard 20mm diameter cylindrical laser pointer module.
• Bearing Stabilization: 2x 624 bearings press-fit directly into the gear hubs for smooth, rigid rotation.

Hardware Bill of Materials (BOM)

Actuators

• 1x Winch Hobby Servo (Pan axis)
• 1x 90-Degree Hobby Servo (Tilt axis)

Bearings

• 2x 624 Ball Bearings (4mm ID x 13mm OD x 5mm Thickness)
  • Press-fit directly into the centers of the 2 herringbone gears to serve as the rotating pivot hubs.

Fasteners & Hardware

• M3 Bolts & Nuts: A small handful (approx. 4-6) for clamping the laser barrel housing and securing servo body flanges.
• M4 Bolts & Nuts: (approx. 2-3) Used as the rigid pivot pins/axles passing through the center of the 624 bearings.

3D Printing Guidelines

• Filament Choice: PLA works excellent for the rigid teeth of herringbone gears. PETG or ABS can be used if deployed in warm environments.
• Infill: 30% to 40% (Grid, Gyroid, or Cubic) to ensure the gear teeth and bearing pockets are completely solid and do not deflect under tension.
• Walls/Perimeters: Minimum of 3 or 4 vertical walls. This ensures the perimeter of the gear teeth and the press-fit bearing walls are strong and resilient.
• Cooling & Speed: Slow down slightly on the gear layers to ensure crisp, accurate rendering of the herringbone angles. Clean tooth geometry is critical for smooth meshing.

Assembly Instructions

1. Press-Fit the Bearings: Carefully press the two 624 ball bearings directly into the center pockets of the 2 herringbone gears. Ensure they sit perfectly flush and square within the gear hubs.
2. Assemble the Geared Axes: Attach the driving elements to your servos, and align the driven herringbone gears (containing the integrated bearings) onto their respective axes.
3. Secure the Axles: Pass the M4 pivot bolts through the center of the gear bearings to create a smooth, constrained rotation axis that locks the herringbone teeth into alignment.
4. Mount the Laser: Slide the 20mm laser pointer module into the barrel clamp on the tilt assembly. Fasten the M3 tensioning bolts until the laser is held firmly.