38mm Fixed Plate Caster Wheel | Directional Guide
Product Overview
The 38mm Fixed Caster from Pro Tronix is a “rigid” wheel solution, meaning it does not swivel. In robotics and cart design, fixed wheels are used in pairs to provide tracking stability. While swivel casters allow for turning, fixed wheels ensure that your vehicle maintains a true straight-line heading, preventing the “wobble” often seen in four-swivel configurations.
Constructed with a high-strength steel housing and a durable polymer wheel, this caster is low-profile and high-performance. It is designed to be mounted to the rear of a robot chassis (working alongside front swivel wheels) or used in industrial furniture where back-and-forth motion is the priority.
Technical Specifications
| Feature | Specification |
| Wheel Diameter | 38mm |
| Wheel Width | ~14mm to 18mm |
| Overall Height | ~45mm to 50mm |
| Load Capacity | 25kg – 35kg (Per Wheel) |
| Mounting Type | Fixed Top Plate |
| Wheel Material | Polypropylene (PP) / Nylon |
| Housing Material | Pressed Steel (Zinc Plated) |
| Supplier | Pro Tronix |
Key Features
Directional Stability: Unlike swivel casters, this wheel is locked in one orientation, providing a steady guide for straight-line travel.
Low Profile: The 38mm diameter keeps the center of gravity low, which is crucial for preventing tip-overs in top-heavy robotic builds.
Floor Protection: The non-marking wheel material is safe for use on lab floors, tiles, and hardwood.
Corrosion Resistance: The zinc-plated steel frame is designed to withstand humidity and light industrial environments.
Common Applications
4WD/6WD Robot Bases: Used as tracking wheels to ensure the robot doesn’t drift sideways during long-distance travel.
Under-Bed Storage: Perfect for sliding drawers or bins that only need to move in a single linear direction.
Mobile Workbenches: Paired with swivel wheels at the front to create a “shopping cart” style steering geometry.
Small Industrial Trolleys: Providing a durable base for slim-profile parts carts in workshops.
You can see our available mechanical and motion components from here: Motors & Mechanical | Pro Tronix



