I Can Do That: Lap Desk

From the August 2011 issue #191
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Portable productivity with a nod to steampunk style.

By Mag Ruffman

The glorious thing about being self-sufficient is that you can usually figure out ways to create what you need.

My latest need arose after a bad case of Burning Thighs Syndrome, a malady caused by sitting on the couch typing on a laptop computer. With my quadriceps performing as heat sinks for the laptop’s toiling battery, I had the hottest legs in Canada.

I switched to writing longhand in a thick journal that never overheated. But to raise the book to a comfortable height for writing I’d have to pile up cushions on my lap, thereby creating a new thermal emergency.

My solution was this perky lap desk, a well-ventilated little unit that adjusts to serve the user’s purpose and thigh thickness.

Oaken-hearted

Start by cutting your desk surface to length with a circular saw (or Japanese-
style handsaw if you want perky rear deltoids). By the way, you might be tempted to use pine, but I learned the hard way that pine turns to mush around the insert nuts and the side pieces end up with hip dysplasia. Plus if you drop it on concrete, the side pieces shatter. Just sayin’.

Using a hole saw, create a grid of holes in the surface for ventilation. To accommodate a computer mouse, leave approximately one-third of the surface unviolated by the holey grid.

To make the desk surface appear thinner and more elegant, create a subtle (1⁄8″) chamfer on the top and bottom edges of the desk using a block plane.

Get Jiggy With It
Next, cut out the side pieces using a jigsaw fitted with a scrolling blade. If you don’t like my curvy design, sketch your own version right on the wood. Once you’ve jigsawed one half of the side piece, you can use the offcut to trace a symmetrical match for the other half.

Scrolling blades tend to scoff at perpendicularity so go slowly to prevent warbles and lumps in your finished side pieces. If you get them anyway, use a rasp to take out the wows. Or you can create The World’s Cheapest Drum Sander by gluing sandpaper to one of the cutouts from the desktop holes, and mounting it on a bolt with lock nuts. Install the stem of the bolt in a drill press or a cordless drill and watch this small sanding cylinder erase your jigsawing sins.

Use a contour-sanding flap-wheel to quickly soften all of the edges on the side pieces. A simple sanding sponge works too if you enjoy the meditative aspects of corrective sanding.

Next, sand the desk surfaces lightly, along with the inside walls of the ventilation holes.

Then drill three height-adjustment holes in the side pieces using a drill bit that’s just a hair bigger than the size of the post on your clamping knobs.

Black to the Future
Ebonize the pieces, if desired. Ebonizing is fun, cheap and permanent. And because the stain penetrates the wood fibers and creates a chemical reaction with tannins in the wood cells, it doesn’t wear as easily as a surface stain.

Oak has a naturally high tannin content but you can accelerate and deepen the effect by pre-treating the bare wood with a concentrated mixture of boiled black tea (for a greenish-black cast), or red wine (for a blue-black tint).
Once the liquid has penetrated and is fairly dry, add a coat of ebonizing “rusty nail” stain (drop a handful of old steel nails, bolts and assorted trail mix – the rustier the better – into a jar of white vinegar. Let it fester for at least two days with the lid off). Enjoy the drama of chemistry as the wood instantly turns deep black. For a deeper hue, add a second coat of beverage followed by more ebonizing stain.
While you’re ebonizing, make sure to treat a piece of oak moulding that you’ll glue onto the desk surface later to act as a ledge that keeps books and computers from slipping off. Sand the moulding before staining to remove any goop or tool marks from the mill.
When it dries the oak grain will be hairy and splintery, so lightly sand all surfaces with #150-grit sandpaper.

Gloss-eyed
Next, give all pieces a clear coat. (I like acrylic driveway sealer because it’s crazy-indestructible.)
The clear coat might raise the grain again, so lightly sand after the first coat dries then apply a top coat. (Acrylic driveway sealer dries a bit shiny so I rub it with #0000 steel wool after it’s cured to bring down the gloss.)

Now glue and clamp the moulding ledge onto the lower edge of the desk surface. If there’s any glue squeeze-out, let it set up a bit before removing it with a scraper.

Finally, drill holes for the insert nuts using a bit diameter that matches the shaft of the insert nut (not including the threads). Drilling into end grain can be a cheek-sucking adventure in steering. Practice on scrap in a vise, attempting to keep the bit plumb. When you do it for real you might want a helper eyeballing the angle of your drill bit and screaming directional cues. Or not.

Finally, use a large slot-head screwdriver to screw each insert nut into the pilot hole until it’s flush with the surface. Then assemble your lap desk with the clamping knobs.

You’ll want to take your new lap desk everywhere including car trips, because most passenger seats lack tray tables – critical for navigational responsibilities and assembling snacks for the driver.  PWM

Download the PDF of the story, which includes the cutlist and patterns.
Lap Desk

Mag is a Canadian woodworker, television producer, writer, comedian and actress. Read her (very funny) blog at toolgirl.com.

Mag’s Additional Tips for the Lap Desk
TIP: Have a reasonable idea of how much your thighs puddle when sitting. I’m 5’5” and weigh 120 pounds and the lapdesk feels very roomy for me. But if you’re beefier in stature you may want to increase the width of the desk surface to ensure quick egress from your lapdesk when you spill a hot beverage or the cat makes hurling noises.
TIP: Hole saws can be a teeth-gnashing gauntlet of despair since they tend to cause tear-out especially on the bottom of the work piece. Invest in a carbide-tipped hole-cutter (www.holepro.com). There’s no tear-out, and the thing cuts like buttah. Also, the slug drops out of the cutter – drops! – without a puncture-wound festival from prying the thing out with a screwdriver.
To make ebonizing stain:
Drop a handful of old steel nails, bolts and assorted trailmix (the rustier the better) into a jar of pickling vinegar. Let it fester for at least two days before using.
To make tea mixture:
Boil ½ cup of loose black tea in 3 cups of water until it reduces to about 1-1/2 cups. Strain the mixture and store it in the fridge or freeze it until needed, since the surface will grow continents of scummy mold when stored at room temperature.

PLAN: Download the free SketchUp plan for the Lap Desk.
ARTICLES: All the “I Can Do That” articles are free online.
Download the complete “I Can Do That” manual.

From the August 2011 issue #191
Buy this issue now
Pages 24-25

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