Drawer Slides Demystified

Like a hovercraft, drawers mounted to today's metal slides glide in and out of their openings as if floating on a cushion of air. But slides come in many different types, and determining which to buy can be confusing. Here's how to pick the best one for the job.

Drawer slides have two mating pieces. The drawer profile attaches to the drawer and slides into or rests on the cabinet profile, which attaches to the cabinet. Ball bearings or nylon rollers allow the parts to move smoothly past each other.

One of the first considerations when choosing a slide is whether you want it visible when the drawer opens. Some visible slides come in various colors (white, ivory, brown, or black) to help them blend better with light or dark drawer boxes.

To conceal slides otherwise visible from the front, add a false front to the drawer box, or build a drawer front with a lip wider than the box.

Drawer slides further differ by how far they allow a drawer to open.
Overtravel slides utilize a telescoping design that lets the drawer extend beyond the cabinet. Use them when overhanging countertops get in the way of drawer access. Make sure the cabinet location provides room for opening the drawer fully.
Full-extension slides also telescope, allowing the full length of the drawer to clear the cabinet. Choose these when you need easy access to the rear of the drawer, as in a file drawer.
⁷⁄₈ -extension slides allow the drawer to extend ⁷⁄₈ of its length—a good compromise between ³⁄₄ - and full-extension.
³⁄₄ -extension slides, as you might guess, allow the drawer to open ³⁄₄ of its length. Choose this type of slide when unblocked access to the entire drawer matters little, or where space limits how far a drawer can extend.

Typical light-duty slides have weight ratings up to 75 lbs, medium-duty up to 100 lbs, and heavy-duty for more than 100 lbs, below.

Longer slides have more robust construction than shorter ones of the same rating. For example, an 18" slide rated for 100 lbs will be stouter than a 16" slide with the same rating. A shorter slide has leverage to its advantage.

With decisions made on type, extension, and weight rating, determine the right size slide for the project.

Taking accurate measurements ensures you buy slides that work in your cabinet. Follow these tips to make sure everything goes smoothly:

Slides come in lengths from 10" to 28". A too-short slide prevents the drawer from opening fully, and one that's too long won't fit in the cabinet. To determine the proper length, measure the interior depth of the cabinet (behind the face frame, if there is one) and choose a slide the next size shorter than that measurement.

Because the thickness of drawer slides and the width of the drawer opening are fixed, best practice is to build the drawer box to fit the difference between the two after assembling the cabinet. For example, most roller slides and side-mount ball-bearing slides require ¹⁄₂ " of mounting space on each side. To use these in a 12"-wide drawer opening, build the drawer 11" wide.

For shallow drawers or a pull-out tray, buy a slide no taller than the drawer or tray.

For frameless cabinets, just screw the cabinet profile to the cabinet side, parallel to the cabinet bottom. On face-frame cabinets, the front of the slide attaches to the face-frame stile, photo below. To align and secure the rear of the slide, manufacturers provide brackets and standoffs that fasten to either the side or back of the cabinet. You can also create your own standoffs from wood scraps.

Use the exact type of screw called for or provided by the manufacturer, as screwheads that stand too proud can prevent slides from moving smoothly. Many slides come with multiple holes and slots to allow fine-tuning drawer position and accommodate a variety of mounting options, photo below.

Also, handed slides must mount on a specific side, photo below; unhanded slides mount on either side.

Now that you know the options, simply consider all installation requirements and pick a slide that best suits the project.

Manufacturers provide several options to add a touch of luxury to a drawer slide's operation.
Soft-close slides slow the drawer as it closes, ensuring that it doesn't slam.
Self-closing slides take the concept further and pull the drawer closed with just a gentle press on the drawer front.
Touch-release slides do the opposite—with a touch, the drawer pops open; useful for sleek cabinets without pulls.
Progressive movement slides provide a smooth glide because all segments move simultaneously, instead of having one segment reach the end of its travel before it begins pulling the next along.
Detent and locking slides hold in a set position until pushed, preventing unintended movement—ideal for small appliance stands or cutting boards.