Drawer slides differ by manufacturer. The majority of them install similarly, and there are two common types: under-mount and side-mount. Under-mount, or bottom-mount, slides are concealed when the drawer is extended, while side-mounted slides tend to support more weight. Another type, with a single center mount, is used on cheap cabinets and provides less stability. Full-extension versions of bottom- and side-mount slides allow the drawer to pull completely out of the cabinet. These install similarly to standard slides.
Cabinets with face frames use bottom-mount slides. Bottom-mount slides are forgiving, meaning that they adapt to a wide variety of styles and measurements. With allowable tolerances of 1/2 inch between the drawer and face-frame, bottom-mount slides are ideal for replacing older wooden slides as new additions to older cabinets without existing slides, or as a component in new cabinets.
Side-mount slides are manufactured by companies such as Blum -- makers of Blumotion slides -- Accuride, KV Hardware and Knape and Vogt. Side-mount slides are typically used on frameless, or what cabinetmakers sometimes refer to as European-style, cabinets. Side-mounted slides are close-tolerance, meaning that there can be little variation in the cabinet, and no more than a 1/8-inch gap between the top of the drawer and the top of the cabinet opening.
There are two types of slides that encompass most versions; ball bearing and nylon roller. Ball bearing slides are the more expensive, and they operate more smoothly than roller slides. The installation of both types is the same.
Left and Right Designations
The instructions for installing slides are basically the same for bottom-mount and side-mount -- the difference is the location of the slides. Identifying the parts is the first step. Open the package and separate the slides into four pieces. One end of each slide should be marked or stamped with the letters DR, DL, CR or CL. The slide stamped DR is for the right side of the drawer; DL is for the left side of the drawer; CR, right side of the cabinet; and CL, left side of the cabinet. The stamped letters are typically on the front of the slide -- that is, the end facing the front of the drawer.
Using a drill/driver and the screws provided with the kit, screw the slide marked DR, to the bottom right of the drawer. The slide should fit flush and behind the drawer front. Use the oval-shaped screw holes, one in front and one in back. Center the screw in the oval-shaped hole. Screw the slide marked DL to the bottom left of the drawer the same way. Screw the slide marked CR to the horizontal rail on the right side of the cabinet drawer opening using two screws, centered in the oval-shaped screw holes in front and back. If there's a horizontal rail in back, the slide attaches to it -- if there's no rail in back, the slide utilizes a boot that attaches to the back of the cabinet. Repeat screwing the CL slide to the left side. Fit the slides on the drawer into the slides on the cabinet, and slide the drawer into the cabinet.
Side-mount slides screw centered to the side of the drawer. Using the designated marks -- DR, DL, CR and CL -- screw the slides to their respective locations on the sides of the drawer and on the sides of the cabinet. Depending on manufacturer, the use of a square may be necessary to level the cabinet slide horizontally before screwing it to the side of the cabinet. Some varieties of side-mount slides screw to the side of the drawer flush along the bottom -- instead of centered.
Center-mount slides contain only two slides -- one for the drawer and one for the cabinet. These slides are typically only marked "C" for cabinet and "D" for drawer. Some versions, depending on how the drawer is built, call for a wooden support to be installed for the cabinet guide or for the drawer to be modified by cutting a notch on the bottom for the slide. Center-mount slides screw to the drawer and cabinet centered in the opening. Oval-shaped screw holes may or may not be available for adjustment. Center-mount slides are very forgiving, and some sideways movement is to be expected.
Jigs and Spacers
Some manufacturers provide plastic jigs that make the job of installing slides more user-friendly. If they're unavailable, homemade spacers can be used to fit slides to cabinets and drawers, speeding up the job, and making drawers fit more consistently and operate more smoothly.
The key to smoothly operating drawers is in the adjustment -- the oval-shaped holes provide the adjustment. If drawers are sticky, rub, grind or are too loose, loosen the screws and tap the slides in the direction needed so that the drawer moves in and out smoothly. Models of side-mount slides may have cam-operated levers that are operated with a screwdriver to lift or lower the slides. When the drawers operate smoothly, add the remaining screws to all the screw holes in the slides.