Red Top Workshop

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Simply Done

Here’s a good one. My wife and I recently shared a lovely dinner at the home of close family friends, both authors. Like the meal, the conversation on these occasions is always stimulating, generally hitting every compass bearing before landing, inevitably, on some aspect of furniture. Uncanny! I should disclose here that the interior of this home is like a comfortable gallery, replete with fine Japanese furnishings, original artwork (created by the hostess) and delightful antique wares. Special! And yet a request was made for a couple of new furniture pieces: end tables that could fit alongside modern chairs to help create a book-lover’s niche within the larger space. Now, there’s a lot to be solved in that statement but such is the power of furniture. As the evening progressed we talked enough about wood, dimensions and functionality for me to get an idea of the priority of requirements before saying our goodbyes. Next morning, once the wine had worn off and both parties had time to think more about the possibilities, the collaborative power of email was employed to finalize a commissioned design after only a few rounds of back-and-forth. Fun!

Design

The customers were looking for something both bold and simple. Easy(?). While their remodeled mid-century home retains many original details, the dimensions have changed and I was afraid that a mid-century modern furniture design would appear too dainty in this enlarged setting. Some related forms, Brutalist, Bauhaus, Danish were explored but these seemed either too curvy, too leggy, or both. Asian items would work for this purpose in other homes but they could never compete here. In the end, we decided on a minimalist design related to an example found online. I consider it a good thing to struggle during the design phase. Pondering different possibilities, their modifications and hybridizations, helps to express what is needed from all that is possible. I often jot down interesting, discarded ideas in the hopes I will stumble upon them to satisfy a future Project design. What? it could happen!

These tables will be large, chunky and symmetrical. Sculptural but not sculpted. No hardware, all wood. The design supports two posture options, upright or reclined, and I can imagine either working to satisfy the original request. And, as always, both the wood species and the board specimens are important components of design. Defect-free material with well-behaved grain would be important for imparting dignity and, after consulting my sons who think a lot about this stuff, it was decided that a richly colored wood was best. Other “looks” are possible but, at last, I was visualizing these tables as pieces that could hold their own in the museum.

Materials

Size rules! The thickness of the table is 3 inches - everywhere - and to achieve this mass with readily available materials I needed to either look for extra hefty 12/4 dimensioned planks (12 quarters of an inch = 3 inches) or use two layers of the more commonly available 6/4 material. I opted for the latter. Even then, it would be a trick to take this “rough wood” dimension and maintain a thickness approximating 1 1/2 inch after dressing both sides even and smooth. By the time a rough 6/4 board is fully surfaced at a lumberyard (so-called S3S) it has usually been reduced to 1 1/4 in. thick. The choices were then: use this to make tables thinner than desired; purchase 8/4 stock and create a LOT of sawdust on the way to the desired thickness; or get creative. As to wood choice, I had my eye on African mahogany, given its uniform yet fascinating grain patterns and the potential to achieve a deeply colored finish. Although not genuine mahogany (Sweitenia macrophylla), this wood (Khaya ivorensis) is the most common of the “mahogany type” woods and has been imported to North America in large quantities for over a century. Today, this wood comes from countries on the West African coast (Ghana, Cameroon, Congo, Gabon, Ivory Coast and the Central African Republic). It is lighter in color and a bit more fussy to shape & smooth than genuine mahogany, but clearly the more sustainable and cost effective choice, making it worthwhile to learn the tricks of woodworking this material. Surprisingly, and perhaps because of its foreign source, the rough “6/4” African mahogany was a full 41 mm (almost 1 5/8 in.) thick. This should make surfacing to a final dimension approximating 1 1/2 in. a snap. Sold!

Dimensioning

Not a lot of manipulations would be needed to prepare this Project for assembly. Once the lengths of all 24 parts were marked in crayon along the board surfaces these could be cross cut to size, planed to a uniform 1 1/2 in. depth, jointed square on one edge and then ripped to a final 6 in. width at the table saw. That was the plan, anyway. In the event, the brawny, 8 ft. long boards turned out to be rather unwieldy to work with at the table saw. Their thick bodies consumed the entire saw blade exposed above my cross cut sled causing burn and some kickback as each cut was completed. Not good - not safe. What I needed was a new saw. (Yes!)

As it turns out, I had been contemplating an upgrade of my 10 inch Makita miter saw to the larger, more advanced model for some time. Don’t get me wrong, I liked my old saw, a founding member of the Workshop, but the new model has some irresistible advantages. In addition to chopping, this 12 inch version also has the capacity to slide across the cutting bed allowing one to accurately cross cut boards as wide as 14 inches. In design it resembles an inverted radial arm saw, that 20th century workhorse now relegated to lumber yards and the basements of diehard enthusiasts due to its inferior safety record. Unlike the radial arm design, the blade of the sliding miter saw cuts as you push it away from you, and only reveals the spinning blade as the cut is occurring. Smart! And, of course, all of the tilting miter features are robustly engineered into this saw, too - it’s a Makita.

Well, I purchased the new saw, mounted it onto a newly constructed bench and it worked great to complete the rough cutting of “6/4” mahogany. The resulting 24 boards (plus a few extras) were then planed smooth on both sides to achieve a uniform thickness of just under 1 1/2 inches. Proper technique would be to “flatten” one side of a board on a jointer before using the thickness planer to make the opposing side parallel and of desired depth, however, the bed on my 6 inch jointer is too narrow to handle this stock and so I used the planer on both sides. The African mahogany boards selected had been quarter sawn at the mill and since this grain orientation resists warp I had the good fortune of starting with remarkably true stock. I think it’ll be okay.

The pattern for this design uses twelve boards per table and the various sized components were marked: A-D. Each piece would be comprised of 2 A’s, 2 B’s, 4 C’s and 4 D’s. Since the lettered parts would be glued side-by side, much consideration was given to match the color and grain patterns for each pair. Anticipating that one table might be used in the upright position and one reclined I also chose what I considered to be appropriate grain patterns for each orientation. Black and red colored Sharpies were used to distinguish between the siblings. Once all assignments had been made, the “best” edge of each board was jointed square and the opposite edge sliced-off at the table saw to a width of 6 1/32 inch. The “extra” 1/32 in. was then trimmed during a single pass through the jointer to give glue-up ready surfaces on 6 in. wide boards. The penultimate dimensioning step was to cross cut the boards to a uniform size = [final length + 1/2 inch] at the sliding miter saw.

It was at this point that I needed to decide how the corner joints would be formed, as the joint type would dictate the order of board assembly. Several alternatives were considered, the main objective being to augment a less-than-ideal “end grain” glueing interface. Even using modern adhesives, fastening boards by glueing to the end grain of wood, a so-called butt joint, produces a weaker than desired bond. This structural weakness is the reason that all of the couple dozen more sophisticated joint types exist. Through one mechanism or another these joints go beyond a sole reliance on end grain glueing. Sparing all of the considerations for/against the unselected options, I decided, in the end, to go with butt joints augmented with mechanical fasteners (screws). It just felt like this piece was too heavy to rely solely on the glued fibers of dead wood, no matter how mingled the joint. But fret not, the screws would be positioned to leave no trace of their existence in the finished piece. Much like the sinew surrounding the joints in our own frame, their cohesive presence beneath the surface will ensure structural integrity. Clever!

Assembly & Finish

Plan in hand, the first step was to edge join the paired 6 inch wide boards to create 12 inchers. 2-3 Biscuits were used within each joint to ensure alignment and strength. It is difficult during this glueing & clamping procedure to exactly align the ends of the boards and so they were assembled as even as possible and then re-trimmed at the sliding miter saw to get a perfectly straight and square 12 inch edge. That’s where the “extra” 1/2 inch mentioned above comes into play. Following this, eight pocket screw holes were drilled into the underside of each “AA” piece in preparation for assembly. The surfaces were then smoothed using a combination of hand planes, card scrapers and sand paper and dry-fit to ensure mutual compatibility.

To assemble, part AA was secured to the two outer leg boards (CC’s) by the use of four pocket screws on each end. This constitutes the only linkage of perpendicular parts. The remaining boards (2 DD’s, 1 BB) were simply laminated, using glue, to the underside surfaces to both provide the desired mass and impart sag resistance along the major beam. Pretty basic, although I was surprised by the challenge of getting all of the boards properly aligned before clamping. Once dried, most of the newly formed “imperfections” could be worked straight and square again by planing/scraping the edges. All remaining features attesting to a handmade origin are (ahem) provided free of charge. Splendid!

The final saw cut was to trim the bottoms of the “legs” at 18 inches in length. Here’s where the sliding miter saw earned its keep as the only tool in the shop capable of handling the task.

From here it was just a matter of smoothing all surfaces with sandpaper and then sealing the wood with finishing products. Following an exploration of various dyes and glazes to deepen the wood’s color it was decided to just leave things alone and let the action of sunlight exert its aging influence over time. After all, the function of most wood stains is to instantaneously achieve the “look” of naturally aged wood. They do this well, but often at the expense of clouding the grain and unnecessarily splotching things up. Stains have their place but not on this Project. However, even when foregoing stains there remain a vast array of finishing options depending on what you wish to accomplish. The objectives here were: 1. accentuate the grain; and 2. impart durability to surfaces that would be used as both table and seat. After a bit of playing around I chose linseed oil to achieve the first goal, and a high grade polyurethane varnish to assure the second. The oil was thinned considerably to reduce viscosity and promote absorption - two applications seemed to do the job. This was followed by three coats of varnish and a final buff.

In their final setting they make a handsome pair.