Overview
A side-mount ball-bearing slide has an outer rail fixed to the cabinet side and an inner rail fixed to the drawer side, with a middle rail and ball bearings between. A three-section (telescoping) slide lets the drawer open fully; a two-section one does not. Wikipedia's drawer entry notes that a soft-close mechanism, which slows the drawer's last stretch and pulls it shut, can be built in. It is the standard modern drawer slide for filing cabinets, desk drawers and utility cabinets.
Types and sizes
- Length ladder: 250 to 600 mm (10 to 24 in), in 50 mm (2 in) steps; the drawer should be about the same length or slightly shorter.
- Side space: the gap the slide needs is the figure in the maker's sheet; 12.7 mm (1/2 in) per side is common, so drawer width is the opening minus 25.4 mm (1 in).
- Duty: light (about 25 kg, 55 lb), medium (about 35 to 45 kg, 75 to 100 lb) and heavy (to 100 kg, 220 lb or more).
- Soft-close and self-close are options; push-to-open types exist.
- Slides are sold as a left and right pair, or a universal pair.
- The example library models a 16 mm slide (about 5/8 in) at 300 mm (12 in) with a 30 kg rating for a desk, and a soft-close 40 kg slide for file drawers.
Where it is used
Modern casework: desks, filing cabinets, kitchen and workshop drawers, anything pulled out frequently or loaded heavily. Period styles used wooden runners (Wooden drawer runner), not metal slides.
Choosing and sizing
Add up the heaviest contents, allow a safety factor of about 1.5, and compare with the maker's rating at the length you need. Specify the drawer box dimensions from the slide: width from the side space, length from the slide length, and a back that clears the slide's rear mount. Match left and right.
Installation
- Set the cabinet rails level and parallel, using a spacer block; fix with two screws first, then the rest through the elongated holes once the drawer runs.
- Mount the drawer rails to the drawer sides, flush with the front bottom edge.
- Use the maker's screws (usually No. 6 or 8, 12 mm / 1/2 in long, pan-head) in pre-drilled pilot holes of about 2.5 mm (3/32 in).
- Connect the two sections; check that the drawer closes, the front lines up and the gap is even.
- Use a story stick for the height of all the slides in a bank so they line up.
Wood movement and species
Metal slides ignore seasonal change, but the cabinet sides move: a solid-wood case side can widen in summer and bind the drawer. Use plywood or a framed side (Baltic birch plywood) and allow the maker's side clearance plus 0.5 mm (about 1/64 in). Screws in particleboard (Particleboard) and MDF (MDF (medium-density fibreboard)) strip under repeated loads; use pilot holes and the shortest screws that grip.
Common mistakes
- Drawer box built to the wrong width: measure the slide's side space, not the nominal size.
- Rails not parallel: the drawer binds one side. Use spacers.
- Pan-head screws too long, poking through the drawer side.
- Mismatching slide length and drawer depth.
Related
- Undermount soft-close slide: the hidden alternative.
- Wooden drawer runner: the traditional method for wood drawers.
- Wood screw: pilot-hole guidance.
Suitable for
Fixes into: sheet, engineered, hardwood.
In our designs
Our example designs model this as BallBearingSlide_16x300, SoftCloseSlide_Std.
Sources
Updated 2026-10-03. Sizes and ratings are typical trade figures drawn from the sources above. A load rating is the maker's rating for one product, not a property of the type: check the maker's own sheet, and test a fit on scrap before cutting good wood.