Pegged oak office desk
Through-tenoned and pegged office desk in solid English pippy oak
This is the first of a family of three desks, each closely related to its siblings but with subtle variations in style. It's going to follow the design that I tested with the earlier pine desk, but will take on board a number of changes I made as the prototype progressed.
The main feature is the three-way joint that's repeated, with structural variations, 22 times within the desk frame. It's made up of a bridle joint and a housing joint that are pegged together with a through tenon. That produces a remarkably strong and visually striking composition.
You can see pictures of the completed piece here.
Scroll down for progress on the project
The pippy oak, from Perton Wood in Staffordshire, has been in store for a year and once the 10-ft-long boards are in the workshop they need to be cut to a manageable size. Here's where heavy machinery comes in useful. First I cut one side roughly straight on the bandsaw.
I straighten out that rough edge on the surface planer, and finally 'rip' along the opposite edge on the table saw. The whole process creates a lot of waste. The log has been de-barked in the sawmill, but you're still left with ragged waney edges that have to come off.
After the initial conversion, the boards go back to the surface planer where I skim the front and back by a few millimetres. This helps condition the wood to the workshop's humidity. I leave it stacked like this for about three weeks to stabilise it before any more processing.
The first major job is to make the desktop. The top will highlight the timber's characteristic 'cat's paw' figure, so the boards need careful selection. About three-eighths of the entire log is pippy; another three-eighths silver rays; and the remaining quarter plain or mixed.
Once the top is prepared I start on the underframe. There are 22 compound joints to cut, most of them connecting three components. Precision is critical and I work to tolerances of a quarter-millimetre. The basic essentials are a sharp 2H pencil and a high-quality rule.
With the pencil marks in place, I need to gauge the various mortices, tenons, housings and bridles, using a standard 19.5mm setting on my antique ebony and brass mortice gauge. The time spent on the mark-up process makes up close to 10 percent of the whole project.
A few of the joints are double housings, which involve cutting notches on opposite sides of the timber. I start with five sawcuts, then carefully chisel out most of the waste along the grain - rather than across it - to make sure the vulnerable edges don't crumble.
To clean up the floor of the housing I use a hand router plane. Unlike an electric router it's silent and pretty much dust-free, and it takes seconds to set up. You can insert different cutters depending on the size of the job and whether you're working across or with the grain.
Once you've reached the right depth, you'll need to clean up the 'shoulders' (the vertical sides of the joint). I've got a tiny Clifton 400 shoulder plane which fits snugly into a 40mm wide housing and shaves off just enough wood to make everything dead square.
There are also lots of mortices to cut. I chop these with a registered mortice chisel, a wide, heavy-duty tool which can stand a lot of whacking with a mallet. But I start by boring out most of the waste with an old-fashioned hand-operated brace and a sharp auger bit .
The joints are individually test-assembled and trimmed for an exact fit. They all work essentially the same way: a bridle (the piece coming from the right) slips over a double housing (going top to bottom) and both are then pegged by a through tenon (pushing in from the left).
Once the joints are finished the next step is to make the panels for the drawer unit. In traditional frame-and-panel construction, they are inserted loose into grooves to allow the wood to expand and contract. I make the grooves with a vintage Stanley 45 plough plane.
Because of the way the joints interlock, most of the grooves in the desk frame have to be 'stopped' - in other words, they don't run through fully from end to end. Using the hand router for stopped grooves instead of an electric router creates amazing curls of wood.
I make the panels for the drawer unit from 120mm wide solid oak and rebate them all round with the plough so they fit in the grooves. I don't sand them: instead, a smoothing plane achieves the perfect finish. The shavings are less than a thousandth of an inch thick.
There are altogether 43 components for the underframe, stacked up here on my bench. Half of them are glued together in a single operation, then the remaining half the next day. It takes quite a bit of planning to make sure everything goes together simultaneously.
Two people have to brush on the glue quickly to avoid it drying out before every part is in place, then the cramps have to go on fast. You end up with a forest of cast iron sash cramps coaxing the pieces into exactly the right position, ensuring every joint links at 90 degrees.
Once the whole frame is glued up I start work on the drawers. The first step is to insert the 'runners' (which the drawers slide upon) and 'kickers' (which stop them tipping when you open them). I also screw in 'stops' at the back to make sure the drawers don't push in too far.
The drawers are made from solid oak throughout, including the bottoms. Once the components and panels are cut out they're jointed with through dovetails at the back and lap dovetails (shown) at the front. I flush them off carefully with a smoothing plane.
If you're careful with your maths the drawers should slide in and out smoothly first time. The fronts are cut from the best quartersawn pieces, so the ray figure really stands out, and I set both drawers in by 11mm to match the rebated panels at the sides and back.
Turned wooden knobs or metal handles wouldn't look right on a piece of furniture like this, so I cut out simple chord-shaped handholds instead. I start with a coping saw, use a rasp to smooth the cut, and finish off with garnet paper held on a shaped block.
Now I can go back to the desktop that I glued up at the start of the project. It takes a whole fleet of planes to smooth it dead flat: a no.6, or fore plane; a no.5, or jack plane; a smoothing plane with first a low-angle, then a high-angle blade; and finally a coffin smoother.
The top fixes to the underframe with 'buttons', little wooden clamps with tongues that slot into matching mortices in the frame. As you screw the buttons in they pull the top tight, but it can still expand and contract across its width as the moisture in the air fluctuates.