Fitting drawers to a case in the traditional “wood-to-wood” way has always been a challenge. And even when a drawer is fit perfectly, there’s no guarantee that it will operate smoothly over the long term. The combination of wood movement and wear can easily undo a lot of careful work.
The introduction of metal drawer slides changed things. Drawer slides make fitting and installing drawers easier, they’ll open and close with less effort, and slides offer long-term reliability. For many heavy-duty, high-use, or general utility applications, they’re a real blessing.
MANY CHOICES. Today there are many types of slides available that are each designed to meet different needs. The trick is choosing the right one for a particular project. This really isn’t all that difficult. For use in furniture, you can generally narrow the decision to a choice between several basic styles. Then it’s just a matter of deciding on a few specifics.
THE BASICS. In our shop, we always choose ball-bearing type slides for our projects, as shown above. This type offers an effortless slide and is very durable. The slide consists of two or three nesting sections. The single section is always attached to the drawer while the remaining assembly is attached to the case (see Easy Installation below). The sections nest together compactly when the drawer is closed and then telescope out when the drawer is opened. The drawer and case parts can be separated for installation of the slide or removal of the drawer (see detail drawings above).
MOUNTING STYLES. A major distinction in slide types is how and where the slides mount to the drawer and case. The drawings directly above illustrate the differences.
Side mount slides are the most commonly used type. The drawer part of the slide is mounted to the drawer side, usually near the mid point or lower. This type of slide requires a standard 1⁄2 " clearance between the drawer and case at each side. So you sacrifice 1" of usable space. This dimensioning has to be taken into account when building the drawer.
Bottom-mount slides are similar to side-mount slides with one difference. Mounting tabs are incorporated into the drawer part of the slide that allow you to fasten it to the bottom edge of the drawer side. The advantage is that positioning this part is easier and the mount is more solid. However, this arrangement requires approximately an extra 5⁄8 " top-to-bottom clearance in addition to the 1⁄2 " required at each side.
A center-mount slide is installed beneath the drawer. (Only one slide is used). The drawer part is fastened to the drawer bottom or a cleat, while the case section is mounted at the center of the drawer opening. The benefit is that the slide is hidden and only minimal side clearance and top-to-bottom clearance is needed. A drawback is that they don’t provide near the support of two slides mounted to the sides of the drawer. They’re recommended only for light-duty applications.
LOAD CAPACITY. This leads us to the next subject. All metal slides carry a load rating. This is the combined weight (the drawer and its contents) the slides can handle when the drawer is opened.
Good quality side-mount slides start at a rating of 75 lbs. Slides with ratings of 100 lbs., 200 lbs., and up are available. However, a 75 to 100 lb. rating is more than adequate for most furniture and cabinetry. As I mentioned, centermount slides have a significantly lower load rating — 25 to 35 lbs.
ACCESS. Another feature that you’ll want to consider is the amount of drawer extension the slides allow. The range is shown in the photo above.
On the low end of the cost scale you have 3⁄4 -extension slides. This type allows the drawer to be pulled out of the case about 3⁄4 of its depth. So access to the back of the drawer may be inconvenient. (Note that center-mount slides are only available in 3⁄4 -extension.)
For a little more money, you can purchase full-extension slides. These slides will open to the full designated length of the slide. For example, an 18"-long slide will extend 18".
In some instances, an even greater degree of extension is welcomed — such as when a drawer is beneath an overhanging top. Here, you may want to use overtravel slides. This type is designed to extend about 1" beyond the overall length of the slide.
You probably won’t want to use metal slides on every drawer project. But it’s nice knowing that when you do decide to use them, there’s almost certainly a slide that will meet the need.
Easy Installation: Drawer Slide Mounting Aids
Metal slides work great on cabinets with face frames — with one minor catch. When installing the case part of the slide, you need a way to bridge the offset
between the face frame and the case side. Wood spacers are one option. But slide manufacturers offer some handy, ready-made solutions that are worth a look.
The upper photo shows inexpensive, easy-to-install plastic spacers that can be used to fill the gap. Once positioned in the case, the slide is screwed to the spacer. The lower photo shows another strategy — an adjustable bracket that fits over the end of the slide and mounts to the back of the case.
