When ordering caster wheels, besides size and tread material, what makes a cart "easy or awkward to use" is the caster type (mounting), which comes in 3 main kinds. This article explains each type, plus the 4-wheel set configurations most used in practice.
The 3 Caster Types
1. Rigid (Fixed)
The wheel only rolls and cannot steer; it is locked in one direction. Its strengths are robustness and keeping the cart "running straight" steadily. Best used as the rear pair to control direction.
2. Swivel
Rotates a full 360°, so the cart steers easily and changes direction in tight spaces. But with all 4 wheels swivelling, the cart is hard to keep straight.
3. Brake
A swivel caster with a built-in lock — step on it to hold the cart in place so it won't roll away. Ideal for work where the cart must stay still for loading/unloading, or when parked on a slight slope.
Popular 4-Wheel Set Configurations
| Set | Configuration | Best for |
|---|---|---|
| SET A | 2 rigid + 2 brake | Steady straight travel + lockable |
| SET B | 2 swivel + 2 brake | Easy steering + lockable |
| SET C | 4 brake | When every wheel must lock |
How to Choose for Your Work
- Tight spaces, frequent turns: use more swivel casters (SET B)
- Long straight runs: use rigid casters on the rear pair (SET A)
- Parking for loading: have at least 2 brake casters
All 3 types are available in both 4-inch and 6-inch sizes and can be mixed into a set to suit your actual work.