Swivel Casters

Swivel offset (also called lead distance or caster offset) is the horizontal distance between the vertical pivot axis of the swivel and the centerline of the wheel axle. When you push the equipment, the wheel trails behind the pivot point -- just like a shopping cart wheel. Proper offset ensures the wheel self-aligns smoothly to the direction of travel. Too little offset causes shimmy and instability at speed. Too much offset increases the turning radius and requires more effort to steer.

A brake locks the wheel to prevent rolling. A swivel lock locks the swivel raceway to prevent rotation, effectively converting a swivel caster into a rigid caster. A top-lock brake does both -- it locks the wheel and the swivel simultaneously. Use a brake when you need the equipment to stay put. Use a swivel lock when you want rigid (straight-line) tracking during transit. Use a top-lock when you need complete immobility.

A precision raceway uses hardened steel races (the channels the balls run in), uniform hardened ball bearings, and tight machining tolerances. This results in smooth rotation under load, consistent performance over time, and resistance to flat-spotting or galling. Economy casters may use stamped (unhardened) races that deform under heavy loads, leading to rough swiveling and premature failure.

You can, but steering becomes difficult. A cart with four swivel casters can turn in any direction, which is excellent for tight spaces but makes straight-line pushing challenging because the casters do not track a consistent direction. The standard recommendation is two swivel and two rigid for general-purpose carts. All-swivel configurations work best in tight quarters where the cart only needs to move short distances.