Tea House Table – Dovetails

Hello and welcome to my blog!  This post continues a series in which I’m building a low table and chair to be installed in a tea house.  Significant progress has been made on the prototype and final chairs, and now they have been put aside to complete the table top.  The table height will ultimately be determined by comfort at the finished chair height and so in order to prepare for that fitting the table top needed to be completed.

The table top section, having spent a few weeks in the shop acclimatizing, was ready for jointing and thicknessing work.  I started the work cutting cross grain to remove the crowned section of the top.  Normally I work a board long grain from the rough, but this piece being both wide and crowned, the work went easier crossgrain.

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The work progressed through to a smoothing stage. While, I know for certain that I will have to refresh the finish after the joinery is cut, I couldn’t help but find out what this mahogany could offer. The shavings are reflected from the finished table top.

Next I trimmed off the sides, followed by trimming the ends square and removing the coated edge.   Generally on rough cut lumber the last 1-2 inches should be removed as it typically hides cracks caused by ends of the board drying faster than the center as the wood is cured.  The green coating that had been applied to the ends prevents those cracks from traveling down the board while it dries.

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Next, the edges are trimmed up with the jointer plane.  I’m using the jointer plane for this to take advantage of the chip breaker, which will keep any grain reversals from tearing out.

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Finally the ends are squared using the same jointer plane.

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On the original design of this table top I had cut dovetailed grooves which received supporting battens, those channels were plugged with ebony and visible from the sides of the table.  In this design I have moved to a new approach.  My new design calls for a rabbet to be cut around the outside perimeter of the table top.

Considering the amount that needed to be removed I cut this edge with the router table, then cleaned up the resulting rabbets with a shoulder plane.

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The resulting edges were carefully chamfered with exception to the bottom edge of the rabbeted surface.  That edge will meet up with the dovetailed batten and so only a very small chamfer was applied to remove the sharp edge.

The exposed end grain surface will be sealed, likely with wax emulsion.

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Next I begin fitting the battens.  Once the dovetails are established I’m simply working a very slight taper into both the batten and the housing so to ensure that the batten will tighten up in the final few taps of assembly.

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The battens, now assembled are tested by pulling on them to ensure that they’re properly seated.  They will help to ensure that the table top moves through the seasons without significant cupping.  For now, the batten ends are left proud.

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The table top is further supported by breadboard ends.  These ends, unlike traditional breadboard ends, are turned up onto the sides to function similarly to the edges of a tray.  This is done more so for its visual effect than for practical purpose since the table top will not be readily removable.

Having made these ends previously I had saved a cutoff to use for future layouts.  This table top is significantly thicker and so some changes needed to be made, but it was helpful to have a template on hand.  I drew the shape onto the edge of a board in preparation for resawing.

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The resawing is done with a Disston rip saw.  Many may wonder why I would rip by hand when a bandsaw is readily available.  In this case it is actually quicker to rip the board by hand than to setup the saw to cut at an angle, requiring me to make a new throat plate for the saw.  Four minutes of ripping and the job is complete.

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I began the process of building the table top weeks prior, and stopped right after cutting the breadboard ends.  Leaving these aside while working on the chairs allowed them more then enough time to readjust after having been resawn.

The boards were then prepared, working the main sides flat for use as a reference.  They’re stacked up upon one another here to level the main surface for planing.  The main surface was then used to reference gauge marks, one side being much thicker than the other.

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Next, the dovetails were cut in, this process is easier done with a wide surface, giving me something to reference off of.

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Then I moved onto cutting the shape.

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Once the shape was roughed out by sawing, I moved onto a series of planes referred to as maru-ganna, more specifically uchimaru-ganna which is a hollow shape.   The opposing shape, which would be the round shape, is referred to as Sotomaru.  The flat surfaces were trimmed up using a ko-ganna with a relatively long sole.

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The battens were then test fitted and continued to be tuned until I found their shape to be appealing.  After which, I marked a center line in preparation for cutting a dovetailed pin, which would retain them in place.

Previously these battens were held in place using only the taper built into the assembly, however having a minimal taper on this table I needed a more assured method of retaining their position.

Shown here, I am cutting a mortise for the dovetailed pins.

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The batten was then reinstalled and the table top marked.

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I sawed along the marks, then chiseled out the remaining waste.

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The resulting cutout was ready to receive a tapered pin.  Please note that while the dovetailed pin is actually tapered in both width and thickness it is only the taper in width which will engage the assembly.  Tapered sections tighten up to form a mechanical lock when applying pressure against end grain.  When tightening against side grain they’re instead working to split the board they’re installed into.

The taper in thickness is made to accommodate a varying thickness in the batten and trimmed back to ensure that it simply presses lightly against the batten sides at the same point when the pin engages the end grain with heavy pressure.

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Next a wedge was sawn to appoximate size then fine tuned with a nagadai kanna.  This kanna has a flat sole ahead of the blade and relief after the blade, allowing it to reference to small parts being used in a shooting board arrangement.

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The pin was then installed and the bottom trimmed into a chamfered form.  This form is very commonly seen on Arts and Crafts furniture, such as the furniture designed by Architects Charles Sumner Greene and brother Henry Mather Green, known simply as Greene and Greene.   The Greene brothers were famously detail oriented, one of those details being the chamfered edges of exposed ebony pins.

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Now that the underside is trimmed to a chamfer, the exposed side on the top face will be trimmed flush.

After the final few plane strokes were taken, the edge grain was nicely exposed leaving a dark contrast to the surrounding edge grain.  As mentioned previously the table top will need to be disassembled and again finish planed prior to final assembly.  That will be done near to the final stages of the build, removing any and all shop wear from the process of building the table.

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I hope that you have enjoyed following along, and I look forward to your comments.

2 Comments

  1. Brian,

    Your writing is almost as poetic as your chair and table are beautiful. I think the finished product will remind me and others of a Japanese Maple. The Maple can look incredibly fragile, yet as everyone (who owns one) knows, it is wonderfully strong and almost sensuous to behold.

    Like

    1. Hi Jim, Thank you for your wonderful comment! It is very much appreciated. It is even amazing to me as I cut parts such as the spindles to find out how strong they become as the form emerges. A very enjoyable process.

      Like

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