A Contemporary Mobile File Cabinet

A few years ago I built some office furniture for a local internet consulting company, and recently they called me back: Not only had they survived the dot-com crash, but they needed some mobile file cabinets. I had already developed a unique look for their computer workstations: birch surfaces surrounded by rounded-over solid cherry edge-banding. The style was crisp, clean and a nice fit for the company’s bright and airy office.

My clients had a few ideas in mind: They planned to move the cabinets around so that people could share files, and they wanted to wheel the cabinets underneath their desks to be easily accessible without occupying extra floor space. Locking casters and the ability to hold letter-size hanging file folders would also be nice. These guidelines created a set of dimensions to work from, and the fact that these cabinets are mobile also dictated that they be finished on all sides so that they could be enjoyed from all angles.

In terms of materials, we ruled out solid-wood panels because of their inevitable cross-grain expansion and contraction, and laying up the veneers myself would’ve been prohibitively expensive.

Fortunately I was able to locate some nicely figured 3/4″-thick birch plywood, and this allowed us to keep the look we were after without spending a fortune or sacrificing durable construction.

Cutting and Edge-banding the Cabinet Parts
First inspect the edges of the plywood, because the joint between the solid-wood edge-banding and the plywood panel needs to be crisp. Although it is tempting, you can’t assume that a factory edge is up to snuff, and a quick glance may reveal numerous dings, dents and scratches. I often end up ripping 1/2″ off of each factory edge. To minimize tear-out on cross-cuts, I use a sharp plywood blade and a zero-clearance throat plate. Feeding the panels more slowly, good-side facing up, also helps keep the cuts free of tear-out.

Once your panels are neatly trimmed to size, it’s time to mill some edge-banding. I use cherry because I like the color that it darkens to, but substitute as you like: I’ve also used walnut with pleasing results. I simply plane the cherry to 3/4″, then rip it into 1/4″ strips. Precision is critical, as inaccurately sized strips will either overhang the plywood panels and need to be trimmed, or they won’t cover the edge entirely and you’ll have to make new ones. I usually mill some extra stock in case I notice a defect in one of the strips that wasn’t evident beforehand. The cut list calls for 12 strips, which allows for one extra.

I own a few clamps that are designed for attaching solid-wood edge-banding, but they end up gathering dust for several reasons. To edge-band a number of panels requires more clamps than I’m willing to buy, and some clamps seem to lack the clamping pressure that I’d like. I also hate lugging heavy, clamp-laden panels around the shop while I wait for glue to dry. My solution is probably not original, but it is highly practical: I use blue painter’s-grade masking tape. It is quick, inexpensive and lightweight. You can even stack a series of panels on top of each other to use space efficiently. And because an ounce of prevention is worth a pound of cure, I use just enough glue to create a tiny amount of squeeze out, which I then wipe up.

Because the edge-banding may overhang a bit, I use a router with a flush-trim bit to carefully remove the offending cherry; a careful touch with a random-orbit sander will remove any glue residue left over. The side panels need to be edge-banded on all four edges, and the top and bottom panels get edge-banded on their front and back edges only. The back receives no edge-banding at all. As a word of caution, veneered plywood is notoriously unforgiving when it comes to sanding. I’ve learned the hard way that there is no adequate method for repairing sand-throughs in the top layer of veneer, so work carefully to ensure that you’ll have to do a minimal amount of sanding.

Assembling the Cabinet
I use biscuits here because they are strong and reliable. In addition, they are invisible once the cabinet goes together, and I didn’t want any filled nail holes or plugged screws interfering with the lines of the piece or interrupting the flow of the grain.

I assemble the cabinet in two steps: First I sandwich the back between the top and bottom, and once the glue there has set, I sandwich that assembly between the sides. For the first step, I clamp the three parts together and line them up precisely. After marking the locations for biscuits, I pull off the clamps and cut the slots. After dry-fitting, I glue it up and wait a few hours. For the second step, I place one side panel flat on the table, inside facing up. I position the top-back-bottom assembly correctly on top of that, and finally place the remaining side on top of it all. With a couple of clamps holding the parts snugly in place, I mark the biscuit locations, then repeat the process I used on the first half of the cabinet assembly.

With a roundover bit in a router, I ease each edge, which softens the sharp lines of the cabinet. By routing the edge-banding after the cabinet is assembled, the inside corners of the edge-banding flow together smoothly, and the eye is swept through graceful little curves that add a fine detail to the finished piece.

Making the Drawers
I build the drawers out of Baltic birch plywood because it is attractive, stable and inexpensive. If you like, you can mill solid-wood panels for the drawer parts – if you do, dress the stock to 7/16″, as the Baltic birch plywood sold as 1/2″ actually measures out at 1/16″ less. Refer to the cut list for the quantities and dimensions you’ll need here. Once you’ve got the drawer parts cut, rip a groove in the bottom of each – you could use a dado blade here, but for a small number of parts like this, I don’t take the time to change blades: I just make two passes side-by-side for the 1/4″ groove.

For this project, I use a rabbet-dado joint to lock the drawer parts together. It is a strong mechanical joint with plenty of surface area for glue. I sketch it full-sized on paper, then set up my table saw to cut the dado on the inside face of the sides.

I use my miter gauge with a stop attached to make sure the dados are cut at a consistent distance from the ends of the drawer sides. This will take two passes. I then cut the rabbet in the drawer fronts and backs with a similar setup – just change the blade height and move the stop on your miter gauge to correctly position the cut. Test the fit of the joint now while you’re still set up to make changes.

Once the rabbets and dados fit snugly, cut out the drawer bottoms. During glue-up, check that the drawers are square by measuring their diagonals. This ensures that the drawer fronts will line up evenly. If a drawer is slightly out of square, clamp it across the longer diagonal and apply pressure until it conforms. Once the glue dries, it should remain in the correct position.

So that hanging file folders can be easily slid forward and backward in the bottom drawer, you’ll need to make two rails that mount on the top edges of the drawer sides. I mill two 20″ strips of cherry to 1/2″x 5/16″. I then make two cuts with the table saw to create the “L”-shaped piece needed. The piece can then be screwed into the tops of the drawer sides – be sure to countersink the heads so that they don’t stick up and interfere with the movement of files across the rails.

Installing the Drawers
I use 20″ Accuride slides because they’re smooth and reliable. Each drawer requires one pair of slides, and each slide can be separated into two pieces: The larger one mounts inside the cabinet, and the smaller one attaches to the drawer. I keep the slides together during installation, and I use plywood spacers to lay them out evenly. With the cabinet on its side, I insert the lower spacer (4-5/8″ wide), the first drawer slide, the middle spacer (6-1/4″ wide), the second drawer slide, the upper spacer (2-7/8″ wide), and finally the upper drawer slide. Then I simply screw the slides in place with three screws. After flipping the cabinet onto its other side, I repeat the process.

With the cabinet upright on my bench, I push the bottom drawer halfway in and place 1/8″ shims underneath it to establish a consistent and correct height for the drawer. I pull out the slides (it should be a snug fit, but not excruciatingly tight) and line them up with the front edges of the drawer. I screw in the front edges of the slides, and then pull the drawer out all the way. With the shims still under the back edge of the drawer, I screw in the back-ends of the drawer slide. The top two drawers go in the same way, except I use thicker shims on top of the bottom drawer because it receives a taller drawer front to hide the tabs on file folders that protrude above the drawer box.

Trim your false drawer fronts to size on the table saw and iron on veneer tape to all four edges. To attach the drawer fronts, I remove the top two drawers and push the bottom drawer all the way into the cabinet. I then set the drawer front into position, using 1/8″ shims on the bottom and sides to ensure a correct reveal all the way around. I use spring clamps to hold the drawer front in place, then I run screws into it from the inside of the drawer. The middle drawer front attaches the same way, but the top one doesn’t have room to get a clamp around it. I solve this dilemma by dabbing some quick-set epoxy on the back of the drawer front then pressing it into position. Flipping the cabinet onto its back and shimming around the edges of the drawer front assures that it will remain aligned. Once the epoxy has cured, the drawer front can be secured with screws like the others.

To attach the drawer pulls, I make a template from a scrap of 1/4″-thick plywood and cut it to the same size as the upper drawer fronts. I draw lines across the vertical and horizontal centers of the template, and center my pull relative to these crosshairs. Once the holes are drilled on your template, you can place it directly on the drawer fronts and drill through your pre-positioned holes. Using a template like this might seem like extra work but, it saves time and guarantees consistent placement on each drawer front.

Finishing it Up
For an office environment, I favor the durability of oil-based polyurethanes, although if I were building this for my home, I might be tempted by the hand-rubbed feel of the newer gel varnishes. When your finishing process is completed, simply screw on four 2″-diameter wheels (locking casters will keep it from rolling around while you open and shut drawers), and bolt on the drawer pulls.

And now, the moment you’ve been waiting for: Go ahead and fill those drawers with all the stuff that usually clutters up your desk.

While I can’t promise that you’ll be more efficient or productive as you tend to whatever paperwork keeps you away from the workshop, I’m confident that you’ll enjoy the smooth, crisp look of your new rolling file cabinet. And the clean desktop isn’t half bad, either. PW

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Chris Gleason designs and builds contemporary furniture.

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