Saturday, October 30, 2010

Shaker Side Tables: By Turning, Turning (I hope) It Turns Out Right

A long walk with the wife and dogs, a hot cup of tea, Pipeline streamed from BBC Radio Scotland, and an afternoon at the lathe -- pretty close to perfection.  The three shaker tables require three different pedestal profiles but all share the use of sliding dovetails to affix the legs.  This joinery is brilliant, efficient, and the bulk of it can be done while the pedestal is still mounted in the lathe.

As you can see from the profile of the Single Drawer Sewing Stand pedestal, the legs will attach to the slightly narrow portion of the base.  As there will be three legs, they will be aligned at 120 degree intervals around the base.  In this case the sliding dovetails will be 3 1/2" long.  I'm assuming that, if you are building along for the first time, that you are working from a set of plans -- they are readily available on the internet.

Shaker furniture maker, Robert Treanor, has a nice article in Taunton's In the Shaker Style, that demonstrates how you can attach a jig to your lathe that suspends a plunge router above your pedestal and allows you to cut the dovetailed mortices.  A couple of photos of my version reveal its simplicity.

The box attaches to the bed of the lathe, and by adjusting the fence on your router you can align the bit to meet the pedestal at the dead top center.  The clamped stop block registers the correct travel of the router and must be adjusted for each of the three steps in this process.  If your lathe has an indexing system, now is the time to use it.  I know that on my Laguna I must turn four holes to get 120 degrees.  I mark these places (in pencil) on the headstock to save time registering each pass.

Step One: Create flat faces on the pedestal
Using a 1" straight/hole drilling bit, I take a light pass over the place each leg will be attached.  As I will use 3/4" stock for the legs, I need a 3/4" wide flat spot. 

Step Two: Rout out the bulk of the waste with a 3/8" spiral bit
With my set up, I rout to a depth of 1/2".  A quick way to set the correct depth is to set the router atop the jig, release the plunge mechanism and drop the bit down to touch the pedestal on the flat spot.  Now, adjust the depth stop mechanism -- with a 1/2" setup block between the stop.  Now when you fully plunge the router it will be 1/2" below the surface.   When you begin routing, hog out the material in a number of passes until the router is fully plunged.

Step Three:  Cut the final dovetail with a dovetail bit
I use Lee Valley bit "16J1755(5/8" by 14 degrees)  When plunged 1/2", the neck of this bit just just reaches the 3/8" width of the spiral bit.  As it is important to have the dovetail's depth match that of the spiral bit, I make a mark on a board and install  the dovetail bit to this depth.

I double check the depth when a place the router on top of the jig, and make the final pass.  Remember, you will make only one pass, at the final 1/2" depth, for each dovetail mortice.  This is possible because you have removed the bulk of the waste with the spiral bit.  The result will look like this:

Next, I'll work on the other profiles, template rout the legs, and cut the dovetail tenons to match these mortices.  Oh, and shoot me any questions if any of this doesn't make sense

Monday, October 25, 2010

Shaker Side Table: Variations on a Theme

It seems that the Shaker aesthetic has never left us.  Grabbing just a handful of my hoarded stash of Woodwork Magazines results in a dizzying array of articles on Shaker design, techniques,construction, and finish.  And like any truly elegant form, it has survived endless adaptations and "improvements" with most of its dignity intact (Shaker entertainment units excepted.)

Sadly though, Sister R. Mildred Barker's fears have come true.  "I would like to be remembered as one who had pledged myself to the service of God and had fulfilled that pledge as perfectly as I can -- not as a piece of furniture."  It seems that the beauty of their creations has outlived the integrity of their lifestyle

But just as it is impossible to separate the music of The Clash from the punk ethos of the '70's, or the fierce cave drawings from early hunter-gatherers, the stark furniture of this radical, short-lived movement opens our minds to the Shaker emphasis on simplicity and fitness-for-purpose.  Good words to use when designing furniture.

We're lucky to have several outstanding interpreters of Shaker design who are very willing to share their expertise on the subject.  At the top of the list is Christian Becksvoort, whose book The Shaker Legacy: Perspectives on an Enduring Furniture Style pays homage to the history, theology and output of this surprisingly varied sect of believers.  I will be building three tables -- the Sewing Stand (pictured above), the Round Stand (below left), and the Two-Drawer Sewing Stand (below right).  While Becksvoort's book does not include plans or drawings, the excellent In the Shaker Style: Building Furniture Inspired by the Shaker Tradition does include some measurements, but due to my contrary nature, I am using these as a reference, not as a template.

Speaking of Templates:
Because of the Spartan design, every element becomes very important -- none more so than the curves and proportions of the legs.  Both the Round Stand (RS) and the Two Drawer Sewing Stand (TDSS) feature sinuous flattened cyma-curved legs, dovetailed into the post.  A simple method to create the dovetails while the post is on the lathe is woodworking's worst-kept secret, and I will cover it later.

For now, the challenge is to draw the profile of the legs and cut them out by hand or machine (When you see photos of clean-cut, smiling' Shakers standing next to their industrial-age machines, you won't feel that you are violating their spirit by firing up the router.)  I have never been happy with the "Draw Spunky" approach of looking at a small drawing on a grid, drawing a larger grid to scale, and then attempting to draw the design to scale on the grid.  I never seem to fair the curves properly.  "Hey, wait a minute, fairing a curve reminds me of that boat-building class that I took."  "How did we fair curves?"  "With a spline." "Right."

So my hybrid approach is to draw out the leg via the grid, cut it to shape (which may or may not be perfect), cut some 1/16" thick splines and hot glue the splines to the template.  If you have a light hand you can follow the cyma-curve but not reproduce the little bumps and flat spots that come with trying to sand the template to shape.  The result looks something like this:

Right off the bat you notice how the spline avoids the little imperfections and fairs the curve.  Just make sure that you secure one end of the spline and ease it into place, holding it lightly, and then securing the other end.  Hold for a few seconds and you are done.  I also have a 1/2" block at the end with a lip that fits into the dovetail portion of the leg and references the piece. Also note (on the center template) that I ran the splines off the end.  That allows you to rout off the end cleanly.  And make sure that you use proper template routing techniques.  Entering your cut on endgrain will make the piece explode.  I don't usually have problems if I climb cut, but be sensible and hold on.

The legs for the Single Drawer Sewing Stand (SDSS) are of the cabriole/snake leg variety and I will work on that, as well as the three pedestal designs in the next post.

Friday, October 22, 2010

Wow, That Was A Long Break

So here's the problem with building guitars -- you start playing them.  It seems that one thing led to another and my time in the shop started to give way to time with the axe.  The things that I did build were either duplicate pieces to round out a set, or items in the same motif that didn't provide enough interest.  I also had some major landscaping projects and an exterior spiral staircase walkway that is in process.

But enough excuses!  I'm back in the shop and have several projects on tap that should spark some conversation.  First, I'm looking at building three shaker tables of differing styles, (all with turned pedestals, some with drawers) doing some steam bending, and continuing to increase my knowledge of Japanese furniture design.

Above you see my new Mike Wenzloff Carcass saw (rip) designed to hand-cut larger tenons (for doors and larger shoji.)  The kit was pretty straightforward and, as you can see, I chose to go pretty simple with the handle carving.  Anyway, thanks for hanging in there, and I'm looking forward to a good season of furniture building.