The tenons, as I said yesterday, go into the mortise like a masculine ‘plug’ into a ‘feminine’ socket — were you thinking sex? Maybe I was thinking electricity, or the flow of water through a garden hose. One way or another, the energy has to come from somewhere, and go somewhere, always.

The tenon is indeed a plug. The board comes from the sawmill already in one state of play. You can leave it as is, and nail or screw one board to another. That will leave both unsatisfied, and then the resulting connection is only haphazard. Sooner or later, the fasteners will fail, and the joint will come apart.

When the tenon is properly shaped, though, it has two narrow and two wide cheeks — the faces that will be inside the mortise — and a shoulder, or broad shelf, where the head of the tenon meets the body of its own board… and which will rest up-side down on the lips of the mortise, the flesh of one board fully married to the the other. Shall we, to the marriage of two sticks of pine, admit impediment?

Indeed we do. The tenon is shaped first by a saw with many teeth. This is no lips together, teeth apart situation — we want lots of teeth to bring the tenon to the rough shape of the mortise we intend to fill, but with a smoothness that cannot be achieved through rough handling. The hole cannot be made larger; the tenon must be trimmed to shape and accept that it must be smaller and move correctly, or the mortise will reject it. Under ideal circumstances, which rarely prevail, the tenon is cut so that it barely needs any trim with a chisel to fit smoothly into the hole which was prepared for it. There’s no extra room in there, of course: if the tenon tries to force its way in, the mortise will crack and the wood will break and likely the tenon will crack. There’s no space for extra girth here. The tenon must be conformed to the shape of the mortise it intends to fill.

And so the chisel must pare away what does not serve. Little by little, the tenon must creep up on the mortise, so as not to startle it

And, perhaps, the tenon’s end must be trimmed true, as well, using a shooting board and trimming plane. Because it’s all about the mortise, not the tenon — the tenon has to accept that it has to be the correct shape for the mortise, not the other way ’round.

And maybe it was always thus? Maybe it has always been the case that the tenon has to abbey that it must be trimmed and shaved, cleaned up and orderly, not for its own sake, but for the sake of the place where it wants to fit and be accepted.

When we speak of the poetics of the tenon, of course, the tenon looks masculine and strong. It’s not as thick or girthy or perfectly dimensioned as its parent board, but it’s easy to make it look shapely and ready to slot in at speed. There’s something decidedly strong about it: it’s square to itself, it’s fully realized, and it’s hefty. Fresh off the saw — or the pen — it feels like you’ve got the geometry right, and everything about it should fit perfectly. As the kids say, 10 out of ten, no notes. Perfect.

In reality, though, the toothy saw or the liquid pen rarely gets the dimensions right the first time. Saws drift. Elbows and wrists and shoulders put too much force into the cut. The plane of the teeth drifts off the cut line. This part of the tenon is too thick, that part too thin. This part of the poem is too terse, that part too wordy. What feels square and well-made, turns out not to be. A word must be shaved here, a syllable there. What Anglo-Saxon two-syllable word can go here, instead of a three-word Latin mouthful, or a four-syllable folderol of Greek-origin pedantry? Can one-sound word go where a syllable is too much?

Or are two syllables just enough?

Little by little, the twist is corrected so that the poem can be offered to its mated reader, a sound-shape to pull into itself like lips and tongue sucking on a hard candy. To bite is to break something — a tooth, a tenon, the wall of a mortise, a heart. The fibrous bits of wood must be pared away, we have to create a shape worth pining for, whether in stout oak or ash; the birch of this must be made a mouthful, no matter how small the morsel. But every part of it must be smooth. It must be as tasty as it looks.

But that requires that the meat of the tenon be properly squared up, pared down to the proper size, and made smooth. If metered, there can’t be any rough spots; if rhymed, there can’t be any dubious matches or knobby patches. If blanked, it must be trimmed to match expectations. Nothing here can be out of place, if it’s to be seated easily; and it has to match what the reader expects, or the joint will break.

Nothing can feel forced — but the excellence of the match is in recognizing that it is the tenon which must fit the mortise exactly, and not the other way ’round. The paring and the planing and the shaping comes from the masculine part of the joint, not the feminine part. If the tenon is too big, the poetry of it will snap the mortise; if it’s too small, it will rattle around in its hole.

Let the thing be shaped exactly to the mortise’s needs, and even give it a final trim off the end, 1/16″ of an inch, no more — so it doesn’t bump the floor of the mortise.

Time to do a little trimming, I guess.