Most equipment needs both: swivel casters for maneuvering and turning, rigid casters for straight-line tracking — a common setup is 2 swivel plus 2 rigid on a four-caster cart, rather than all one type.
All-swivel setups turn easily but can wander without direction; all-rigid setups track straight but are very hard to steer. Mixing both gives controlled maneuverability.
Any new cart build or caster replacement project — this is one of the first decisions to make, before capacity or wheel material.
Defaulting to all-swivel for maximum maneuverability. Without any rigid casters, long equipment often wanders or crabs sideways under push rather than tracking predictably.
What's the standard mix for a 4-caster cart?
Commonly 2 swivel and 2 rigid, giving controlled maneuverability and straight-line tracking together.
When would I use all swivel casters?
Mainly on equipment that needs to move in any direction with no preferred straight-line path, and typically only on smaller, lighter equipment.