Glossary

Bottom roller

A wheel fixed under a tracked sliding gate. It runs along the V-track or inside the U-track and carries the gate's weight.

A bottom roller is a steel or nylon wheel in a bracket that bolts or welds under a sliding gate's bottom rail. The wheel shape matches the track: a V-groove for a V-track, flat with side flanges for a U-track. A gate usually runs two of them, one near each end.

Residential bottom rollers come in 75 to 120 mm diameter. Heavier commercial gates step up to 150 to 200 mm. The bigger the roller, the more easily it crosses dirt, sticks, and minor track obstructions without binding.

Bearings are a wear point. Sealed ball bearings in good rollers last 5 to 10 years before they want replacement. Cheap rollers with bushings will go in 2 to 3.

Related terms

V-trackA steel rail with a V-shaped top, set into the ground. The gate's grooved wheels sit in the V and roll along it. The common track for a tracked sliding gate.
U-trackA steel channel set into the ground with the open side up. The gate's wheels run inside it. Another option instead of V-track for a tracked sliding gate.
Top roller (guide roller)On a cantilever gate, a pair of rollers fixed to the post. They hold up the cantilever rail and let the gate slide, and they carry the gate's weight.
Sliding gateA gate that slides sideways to open, instead of swinging out. Picked when there is no room out front for a gate to swing.

Used in these CAD60 models

Battened Sliding GateParametric sliding gate with a rectangular hollow-tube frame and vertical battens face-fixed to the front. Supports optional tail extension for motor automation and optional L-piece top rail.
Slatted Sliding GateParametric sliding gate with a rectangular hollow-tube frame and evenly-distributed slats. Supports vertical or horizontal slat orientation, optional tail extension for motor automation, and optional L-piece top rail.