The Coffee Table Base

Once the top was shaped, flattened and sanded, it was time to tackle the base. The base of this table consists of only four parts. The legs and bottom rail are half-lapped together, which is a pretty simple joint to cut, normally, but in this case the legs are canted out at a 10 degree angle. Cutting the angled joint is still pretty straightforward, but requires an extra jig, and some thoughtful planning.

The secret to a well-fitting joint is to do all the angled milling operations with the same table saw blade setup.  After setting the blade to 10 degrees, I first trimmed the top and bottom faces of the legs. Next, without moving the blade, I cut the angled half-laps in the bottom rail. To do this, I used a crosscut sled. You can also see in the photo how the rip fence and a stop block defined the limits of the cut as the material is nibbled away. That meant that I could cut both sides with only a single setup by just flipping the rail, yielding two dadoes exactly the same size and perfectly symmetrical.

 

While the blade was still tilted, I also cut the front and bottom parts for the leg dadoing jig. This jig was used in conjunction with my normal 90 degree crosscut sled to cut the mating dadoes in the legs. Stop blocks again defined the limits of the cut, and allowed me to cut both legs with a single setup. The same sled setup was also used to cut the dadoes for the upper rail.

The ragged edges left by nibbling with the table saw were cleaned up with a chisel, and with all the joint halves cut using only two setups, there was no doubt that the joint would fit properly.

Now that the joinery was cut, the various parts could be shaped. First, the bottom rail's upper half was given a parabolic arched profile. Using a paper template, the shape was drawn onto the rail ends, and the majority of the waste material removed with a couple of passes on the table saw. The profile was then refined with a plane, scraper, and sander. By leaving the lower half of the rail square, the joint was fully maintained.

Shaping of the legs was done in two steps. First, the outer edges were curved to give a softened trapezoidal outline. This was done on the band saw, and then faired with a belt sander.

Next the sides of each leg were given a thumbnail profile. This was done by first laying out a center line down the face and relief lines on each side, then using a compass to lay out the curve.

Then it was back to the plane and sander to fair it all out. The base was now complete and ready for finishing.

A Monumental Coffee Table

Well, its a new year and its time to get back to the too-ignored blog. So here goes.

Currently in the shop is a very substantial coffee table, made from 3" thick slabs of Claro walnut. 

Unfortunately, unlike the rendering, the actual top slab has some significant checking going on, so first order of business was to get that under control. This is an air-dried slab, so its moisture content is only down to about 12%. That means it'll experience more seasonal movement than a fully dried piece would, but the big crack can be stabilized using butterfly keys (a technique popularized by the great George Nakashima). The first step was laying out a pleasing arrangement, which I did with paper cut-outs of various sizes.

After the layout was set, the butterfly keys were milled from 4/4 wenge stock using a simple band saw jig.

Once the keys were milled and inlaid into both the top and bottom surfaces, the edges were shaped. The curves were rough cut with a jig saw, then faired using a hand plane and sanders. You can see the installed butterflies in the photo, as well.

Here's what it looks like with all the edges shaped and faired.

Check back periodically over the next few weeks to see how the base unfolds....

 

Houston, The Behemoth Has Landed!

Well, after much work and luck, the desk has been delivered and assembled. One of the biggest challenges was getting the various components of the desk, a small drawer base, the huge 8' long side case, and the big walnut slabs, to all fit together. Since it bridges the two base cases, attaching the main desktop slab was the trickiest. Its attachment to the small drawer base was pretty straightforward - four solid aluminum posts were screwed to the underside of the slab with hanger bolts, then the case was lined up and bolted to the posts from the inside.

Attaching the slab to the long side case was a little trickier. In earlier posts I described both the battens that hold the slab flat, and the milling of two walnut rounds that support the slab. The trick was to mill shaped dadoes (grooves) into the rounds that would receive the batten and keep the slab aligned. This turned out to be easier than expected using the plywood sled that was used to mill the rounds in the first place.

Each round was remounted into the sled after it was marked with alignment marks so that the sled acted as a straight, constant edge that could be indexed against the tablesaw fence.

Then, with the alignment marks still intact, the rounds were lined up with each other and with the center of the case, so that they could be attached in line. Aluminum pins were then installed to maintain the alignment of the rounds and the batten, and to keep the batten from shifting.

Once everything was lined up, the slab covering the back half of the case could be positioned and attached, then the doors and drawers reinstalled, and voila.

As you can see, there's a second set of aluminum posts that support a floating frosted glass shelf, as well as aluminum drawer and door handles, which tie the whole piece together. For a little extra flair, the panels on the fronts of the cases are veneered with custom cut pieces of figured walnut. In the end, this desk, which has both natural and tailored design features, as well as both rustic and sophisticated detailing, comes together as a unified whole with a one-of-a-kind presence.

A Statement Desk

My newest commission is a large desk utilizing substantial slabs of walnut. The design is in the final phases of tweaking, but the slabs are already in hand. They came from Jim Baker in Gilroy, who specializes in large scale tree milling. They were then flattened and dressed on an impressive 5' x 22' CNC router by FrameCom, also in Gilroy.

The main desktop slab measures over 3' x 7'! This is the smaller of the two pieces. They should look great with a little sanding and some finish. Stay tuned for more as this piece develops.

Stylish Bench from Walnut Slabs

One of the great things about making wood furniture is that sometimes you get the chance to let nature do most of the work - then all you have to do is add a little bit here and there, and you get a great looking piece. This bench is just such a case. The walnut slabs, sourced from an orchard in the San Juan Bautista area, are the real star. All I had to do was add a little styling in the form of legs, and voila. It got a great response at the Marin Art Festival, and now is available for purchase. It measures roughly 70" long x 35" high, x 28" deep.

This is a look at the back and leg structure.


As you can see, the material speaks for itself.

Designing for Movement

Even though its been dried and milled, solid wood lumber still experiences expansion and contraction with changing environmental conditions. This movement must be taken into account when building furniture because if seasonal movement is restricted, the internal forces brought to bear can cause cracking and splitting. The challenge with this piece was to come up with a joinery system that would allow the spare design, just two slabs and two leg assemblies, to be strong and rigid, while still allowing movement of the slabs. Because the grain orientation of the seat and back supports are perpendicular to the grain of the slabs, simply doweling, tenoning, or screwing the pieces together would not allow the slabs to move, and result in failure. The answer that best suited this project was to attach one edge of each slab with a mechanical fastener (aka, a screw), and the other edge with a form of sliding dovetail, known as a blind keyhole dovetail. In this type of joint a dovetail-shaped tenon fits into an elongated sloped-sided mortise - the dovetail shape keeps the slab firmly snugged to the leg structure, but allows the slab to expand and contract by sliding along the tenon.

This is a picture of one of the mortises. You can see that half the mortise is square in profile, to allow the tenon to be inserted, while the other half is dovetail-shaped.

This photo shows one of the back supports. You can see the attachment screw near the top of the support that is the fixed attachment point, and below it the hard maple dovetail tenon that will slide into the blind mortise. To the left you can see the other leg assembly already attached to the back slab.

This next photo shows the similar arrangement for seat slab attachment. You can see that the front of the seat slab will be fixed, with the rear of the slab allowed to move in and out.

Here is the fully assembled bench (upside down) showing the slab-to-leg assembly attachments.

Stay tuned for more images of the final, finished piece. Thanks!

New Bench Project

With the Marin Art Festival coming up fast, I wanted to create a new piece to show at the festival. I've had a couple of matched walnut slabs from an orchard near San Juan Bautista for a few years, and have thought from time to time that they would make a great bench. So, this seemed like the time to get off the stick and make that happen. I'm going to keep the slabs in as raw a form as possible, in other words, not hiding the worm holes and checks. To counterpoint that roughness, and give the piece a little sophistication, I'm going to use wenge for the sculpted leg structures. Although I wouldn't be so bold as to suggest that my work is at their level, I think of this as a sort of a Kagan meets Nakashima design. Hopefully, I can get it done in time!

Here's a picture of the slabs and the leg blanks. You can see the final leg form from the plywood template. The slabs will be attached to the flat seat and back surfaces. Notice the great colors in the slabs that have been preserved by letting them air dry, rather than kiln drying. The only down side to air drying is that the moisture content of these pieces is only down to about 9%, which is a little high for furniture. So, I'm going to have to design joinery that will allow for extra movement.