Chopping Holes in the Table

One of the best things in life is a wife that says, “Why don’t you take the day in the shop today,” on Valentine’s Day. There’s not much else I can say about that. I’m a lucky guy.

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After consideration, I decided to stick with lyptus for the secondary wood. I haven’t tried to cut dovetails in it yet, but it can’t be much worse than the hard maple I started with. All the pieces are cut and dimensioned, including two 1/4″ panels for the drawer bottom. The lyptus machined extremely well, and I like the way it looks with the mesquite. A few pieces still have to be cut to final length, and they will actually be cut to fit the openings to ensure that they’re tight.

The first step in cutting the joinery is cutting the legs to length, and establishing the top and bottom angles. At this point, the legs are identical blanks – same size and dimensions. But that’s about to come to an end, and this is where you have to start being really careful. I can’t overemphasize this: label your parts clearly. Each leg is different. The two back legs have one mortise in the front, and two on the inside, facing each other. The front legs have one mortise in the back, one on the inside, and a second 1/4″ square mortise towards the top for the front drawer support. Because the legs are angled outward front and back, the placement of each mortise is crucial. If I get two of my legs switched, I’ll ruin a leg by cutting a mortise in the wrong place. That means squaring more wood, and cutting and gluing up another leg blank.

The legs and other mesquite parts are labeled in white crayon. It’s much easier to read than darker pencil lines against the dark wood. Each leg is labeled on its outside front- or back-oriented face, with it’s left/right position, and an arrow pointing out the top. It’s extremely easy to cut something on the wrong end of a leg, which is just as disastrous as the wrong face.

The first angled cuts (on the top and bottoms of the legs) are made by hand, with the guide block I discussed previously. I want these cuts to be fine and as free of splinters as possible, so the cuts are made with a Japanese dozuki saw – an extremely fine crosscut saw. Its teeth are somewhat fragile, and can’t be resharpened. I was a little concerned about damaging them in the hard mesquite, but they handled it nicely.

The leg and apron joinery is mortise-and-tenon. If you’re not familiar, it’s basically a tab-and-slot system. The holes are called mortises, and can be cut several different ways. My intention for this project was to do as much of the work by hand as possible… but that resolution just failed.

Hand chopping mortises is difficult, difficult, slow work. We get used to the speed and ease of work with power tools, and forget sometimes that centuries of beautiful furniture was cut strictly by hand. Mortises are cut by hand with a mallet and a heavy-bladed mortising chisel. Mine works fine, and I’ve done it before – but never in wood as hard as mesquite. I started cutting a mortise on a test piece to see how it went, and I quickly discovered that I’d be working all week to cut even these small 1/4″ mortises by hand. The wood is just so tough that it becomes an incredibly labor-intensive job. In this case, the ease of work provided by power tools wins out.

The mortises are laid out with pencil marks, with the area to be removed marked with X’s. This is pretty crucial markup, because although the lower aprons are centered on the legs, the upper aprons are offset. The positioning of the offset of the aprons is not specified anywhere in the plans… which means that the lower aprons have to be cut to fit once the upper dimensions are established. These plans have turned out to be rather sketchy, in my opinion. There are several places I’ve found where dimensions aren’t specified, offsets aren’t indicated, and so on. In this case, I’ve worked backwards from the thickness of the aprons, the thickness of the tenons, and made an educated guess about the best offset.

There are several different ways to cut mortises by machine. I use a mortising attachment for my (fairly cheapo) Delta drill press. The cutters are best described as four-sided chisels, with a center auger bit that cleans out the bulk of the waste. Once it’s attached and aligned, it makes short work of cutting the mortise. The drill press cuts downward to the depth set, and the waste comes out the side of the hollow chisel. It takes about eight or ten strokes to cut the mortise, and the sides are pretty smooth. A little cleanup with a file and chisel is all that’s necessary.

The mortises for the side aprons are cut to the same angle as the legs. In this case, there’s not much way to use the guide block I made to align the mortising tool, so the legs are supported by a small piece of scrap wood which determines the angle of the leg on the machine. The scrap is clamped in piece, and the leg slides across it when it moves to maintain the cutting angle.

Side note: Handling the legs and realigning them for the mortises started to get painful. The side edges of the legs are extremely sharp, and the hard mesquite was starting to tear my hands up. Two or three minutes with an apron plane softened the very sharp corners so they were easier to handle – which is a step I was going to have to do sooner or later anyway, and doesn’t affect the layout of the joints in any way.

Once the side mortises are cut, the mortises for the back apron are cut into the back legs, on an adjacent side; then the lower mortises are laid out and cut. The 1/4″ square hole for the drawer support is cut using the same technique. Since the lower apron and back apron are parallel to the legs, the scrap support to establish the angle isn’t necessary. Once the mortises were finished, I examined the chisel used to cut them. Surprise, surprise… it’s completely trashed. All four chisel points are dull. That means it’s going to have to be resharpened before it can be used again. I don’t have a sharpener for these – it requires a cone-shaped sharpening tool to get the inside of the chisel. Looks like I’m going to have to order one. This is tough wood.

The lower aprons have a 1/2″ x 2″ through tenon, secured with pins in the front and back. It also has to be cut at the angle of the legs, so I decided to use the 1/2″ mortising chisel on the machine to cut those as well. That’s where things started to go wrong.

Problem #1: It’s too flippin’ tough. The 1/2″ chisel won’t cut through the wood like the 1/4″ chisel does. It jammed… it tried to smoke and burn the wood… it took forever to get just the first of the four cuts made for one of the two aprons.

Problem #2: Because this mortise goes all the way through the wood, it needed to have some support for the back when the chisel came through. I should have backed up the wood with another board, to prevent tearout. When the chisel finally came through, it tore out a piece about the size of my thumbnail adjacent to the chisel. Fortunately, it won’t show – the tearout was all in the area that will be cut away for the through tenon. But I’m going to have to watch that; it’s a mistake I’ve made before.

Problem #3: When the wood started burning, I saw a tiny hot coal go into the dust collector. That’s bad. The odds of it starting a fire in the dust collector bag are very, very small, but I won’t take chances. I don’t think I want to explain to the wife-unit how I managed to start a huge, explosive dust fire in the attic on Valentine’s Day. But that’s okay; I needed to empty the bag anyway.

The second and third problems can be solved – by slowing down on the cuts and not trying to rush the machine, and by backing up the wood to prevent tearout. But the best solution, I think, is going to be to cut these through tenons with a coping saw. I’ll have to be careful, and cut a little shy of the line and clean it up with a chisel to ensure a tight fit for the stretcher.

In one of my classes at Woodcraft, Howard Hale told a story. He had been to a homestead museum in the Northeast, and it had a preservation of an 18th-century woodworker’s shop. In one of the displays was the craftsman’s diary, and the page it was opened to had this entry:

“Cut three mortises today.”

Circled above that, was this notation: “Good day!”

It’s easy to forget how much hard work was involved on operations we think of today as pretty easy. I cut twelve mortises today, by machine, and I still feel like that was a good day.

Next: Finishing the mortises, starting the tenons, and back to the top (again).

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Labor

To me, the joinery and detail work is the most fun part of any project.  The dimensioning of lumber? Well… not so much.  It is, however, necessary – and kind of gratifying when you have the pile of dimensioned lumber in front of you.  But it’s just straightforward, repetitive work jointing, planing, cutting, trimming. It’s also extremely loud.  The alternative is to dimension by hand and plane to thickness, but there’s a rational limit to the time I have if I’m to finish this project in my available time. Angus doesn’t like the planer or jointer noise, and as you can see, he’s glad this part is over.

As you have probably seen, cutting into the wood sometimes reveals its beauty.  But it can also uncover problems.  For example, this crack – known usually as a “check” when it appears in the end grain, as it does here – was internal to the board. It didn’t appear until the board was cut.  It has to be cut away to prevent the board from splitting later.  It could  be glued together with superglue, and would probably be strong enough.  But I’d rather remove it and not take the chance.  Fortunately, I have stock to spare for this project.

At this point, all the mesquite lumber is cut, sized, and squared.   That leaves some poplar for the drawer frame, and the secondary wood for the drawer itself. You’ll probably notice that most furniture uses different wood inside the drawers and for the drawer sides than the rest of the piece is made of.  Traditionally, that’s called “secondary wood”, and refers to a a less-expensive wood used for parts of the piece that don’t readily show. It also saves on the consumption of less-sustainable woods (such as mahogany, which is typically harvested from old-growth forests).

To me, it’s also about how the primary and secondary woods look together.  The original Stickley table from the plans was white oak and maple.  This one is mesquite, and it makes the maple look bright yellow next to it.  My first choice for secondary wood was sassafras, but I’ve decided that it’s too light and soft for this project. I’ve settled (for now) on a sustainable hardwood called Lyptus.  It’s harder and denser, and I like the way the two woods look together.

This also creates another challenge.  There’s no plywood faced in Lyptus to use for the drawer bottom.  Which means resawing the lyptus into 1/4″ panels, and making a slatted drawer bottom.  I may yet decide to back off and go with maple, since I can get maple-faced plywood… this is going to be a lot of additional work for the inside of a drawer. Stay tuned.