Grass-Seat Chair - Canadian Woodworking Magazine

Furniture Project: Nakashima's style reflects the unadorned beauty of wood and other natural materials

grassseatchair_lead

Grass-Seat Chair



Illustrations by James Provost 

Chairs are among the most complex and challenging woodworking projects to build. However, with patience and careful workmanship, it is well within the scope of anyone possessing intermediate level woodworking skills.

George Nakashima (nakashimawoodworker.com) had a seminal influence on what has been called Modern Style Furniture, a direct descendent of the Arts and Crafts movement that was popular in the first half of the 20th century. The two styles shared the philosophy that beauty in design came from simple lines, little adornment, functional utility, and especially, allowing the natural beauty of the wood to show itself. This meant little or no paint was used on these pieces, but rather stains and finishes that highlighted grain and other wood features. One way in which the Modern Style differs from Arts and Crafts is the belief that mass production would bring their utilitarian designs to everyone. The Arts and Crafts focus on the individual craftsman and hand production resulted in much lower output, higher prices and ultimately those pieces being available to the few, rather than the many.


grassseatchair_illustration1

grassseatchair_materialslist

George Nakashima was an influential Japanese-American modernist furniture designer in the mid to latter part of the 20th century. His early work designing wooden buildings in Asia and the influence of far eastern philosophies led him to a life of design that tried to reflect the unadorned beauty of wood and other natural materials in his work.

I came to his designs the same way he did; through Arts and Crafts, which makes sense because the Modern Style shares the same appreciation of simple beauty. During general reading on the topic I saw and fell in love with this elegant chair. No plans were available, so armed with only basic dimensions and two black and white photos, I scaled all the chair’s measurements. I used hand tools almost exclusively to build this chair, but a machine made chair would still be true to the original designer’s philosophy, and take much less time to build. Nakashima often used cherry and walnut in his work, but I chose mahogany.

The Seat Frame
Start by milling the seat frame pieces (A, B, C) close to size, and then hand planing them to final size, ensuring that all surfaces are flat and square. Notice the subtle angles on the underside of the front frame sections; hand plane this to around 10º before you cut the full width ½" tenons on piece B. The frame is angled inwards from back to front by just a few degrees, so you will need to cut the tenon shoulders on front and rear frame pieces (B, C) parallel to the side (A) pieces, not at right angles to the tenon face.

There are 14 holes that need to be drilled into the frame. Four of these holes are on the edge of the frame, six are on the top of the frame, and four are on the bottom of the frame.

Mark and drill the four ⅝" holes into the edge of the side frame (A) pieces. The woven seat will be anchored to the frame through these holes. The holes for the side rail spindles (G) are set at complex angles and are a different diameter from the back rail spindles but are the same diameter as the back rail spindle holes. The holes are ⅝" at the base (slightly smaller than the ¾" diameter of the spindles shoulders) and drilled at 15º out and 15º forward. I made a 15º jig to lay on the drill press table and added the second (complex) angle by adjusting the drill press plate itself.

As mentioned the holes for the back spindles (H) are ⅝", and are set at a simple 10º angle, tilting back. I also added corner braces (J) and you can make them now and test them for fit – remember, the angles of the seat frame are not square, but I cut the braces square and then used a small block plane to trim them to fit snugly into their respective corners. I pilot drilled and countersunk them, and set them with wood screws.

On the underside of the frame drill the 1" holes for the legs. Test fit the frame assembly, but don’t glue it together until everything else is ready.


grassseatchair_illustration2
Jig for drilling 15° holes

Legs and Spindles
There are four legs and eight spindles to be made. You’ll find it helpful to make a couple of patterns (balsa wood is a good choice) and use them as a guide for shaping the legs and spindles. I used a drawknife and spokeshave on a shaving horse to make the legs and spindles. You could also turn them on a lathe. Aim to fit the legs and spindles snugly in their holes, but if you have a circular tenon cutter (leevalley.com) this will give you a tighter fit, faster, and the result will be stronger.

The legs (D, E) are narrowest at the bottom, which means the widest part of the leg (the belly) is slightly above the midpoint. This means that the tapering is a bit more gentle from the belly to the bottom of the leg than from the belly to the top.

The leg spindles (F) add strength to the chair. They are shaped similarly to the legs but on a smaller scale and the curvature is symmetrical from front to back. You will need to drill holes in the legs for the leg spindles. The spindles are parallel to the side frame pieces and therefore their corresponding holes in the legs are drilled at 15º. Because the legs go into the frame at an angle, and the spindles go into the legs at an angle, you have to cut the tenon shoulder on the leg spindles at the same 15º angle (parallel to the frame).

If you turn the leg tenons on a lathe (recommended as the better fit will strengthen the chair greatly) the tenon shoulder (where the leg meets the tenon) will of course be perpendicular to the long axis of the leg. Because the leg is fixed to the chair frame at a 15º angle the shoulder of the tenon (the part that should be flush with the bottom side of the chair when the leg is inserted) will not be parallel to the bottom of the chair, as it would be if the leg were coming straight down. So, you will have to trim a bit off the shoulder (by hand) to add the 15º angle and ensure a nice looking fit. This problem can be avoided if you cut a tapered mortise and fit a tapered tenon (i.e. with no shoulder), which depends on what type of drill bit you are using.

The back legs are ¼" shorter than the front legs to give the chair a slight backwards tilt – a subtle but very effective design element. I made all four legs the same, initially, then just trimmed the feet of the back two legs.

The back and side spindles (G, H) are narrowest where they join the back rail (I); the belly, however, is not quite at the midpoint, but slightly below. Therefore, the tapering is more gentle from the top to the belly, and a bit more acute from the belly to the bottom. The legs should fit snugly into their holes but not too tight. If you pound them in you risk splitting the side frame – remember, snug but not tight!


grassseatchair_illustration3
Trim leg tenon to fit

Assembly
Final sand all the parts, and then glue and assemble the seat frame. Ensure the frame is still flat after tightening the clamps or the chair will be a rocker whether you like it or not. Optionally, you can use drawbore pins to secure the tenons. The frame is very strong, especially with the corner braces, yet remarkably light. Next, test fit the leg spindles into the leg holes and the legs into the frame. It is a bit tricky; the leg holes face in towards each other so that, as they slide in, they will also close on the leg spindle. It’s not hard but you have to loosely insert the leg spindle, and then cinch it together as the legs go into their holes. Once you have tested the fit, and are satisfied all is well, add a thin coat of glue, and fit the parts back together, and clamp. When they are all tightened and the glue is dry, it is quite solid.
 
Back Rest
I made the curved back rail (I) by laminating seven ⅛" x 2 ¾" x 40" pieces of mahogany to produce a finished piece that was ¾" x 2 ½" x 39". To form the arc for the back rail I made a simple jig that consisted of two parallel rows of ¾" holes drilled into a 36" square piece of chipboard that was 1 ½" thick (two sheets screwed together). The dowel holes, spaced 3" apart, were drilled in the shape of the arc I wanted for the back. Three-quarter inch x 6" dowels were glued into the holes. The 3" spacing is an arbitrary distance I decided on; the main thing to consider is that you need enough dowels to provide a smooth arc, with the strength to hold the wood to be bent, but few enough that you can fit all of your clamps between them to compress the wood while it is in the jig.

After spreading glue on all the faces of the laminates (except the two outside faces), quickly stack and push them in between the rows of dowels. Apply small C-clamps (3" or 4" sizes work well) about every two to three inches to provide sufficient compression. Make sure that there are no unsightly gaps. Leave the sandwich in the form for 48 hours or as long as necessary for your glue to harden. You can then hand plane or joint the top and bottom of the back to 2 ½" in height. Slightly round the top edges of the laminate stack so as not to expose too much of the laminations from the front and back.

The back is also tapered in both dimensions as it curves toward the front of the chair – the height narrows to 2 ¼", and the thickness gradually to ⅜". These tapers can be done with a hand plane, rasp or sandpaper, but should be done after the back comes out of the jig so that you don’t have to worry about the pre-shaped pieces coming out of alignment as they are setting.

Using the same jig that you used to drill the seat frame holes, make the corresponding holes in the underside of the back rail. It’s a bit tricky to get the two sets of holes aligned correctly. I tapped the back spindles (H) into the seat frame, placed the back rail over the spindles, and then marked the location where each spindle met the underside of the backrest. Remember that the holes in the backrest are facing backwards and in - the complements of the holes on the frame (drilled out and forward) so they are in effect the reverse.
 
Seat Construction
The texture and colour of the sea grass seat beautifully compliments the wood in this chair and helps to make this chair look, as well as feel, friendly, inviting and comfortable. As rustic and simple as the seat looks, it can actually take a long time to get right – trial and error is the name of the game. I’d advise getting everything you need for this section ready, then place yourself in front of the TV and put on a favourite movie – or series!

The sea grass seat should be added after the legs, but before the side spindles and back, as it is a tricky job and you need all the clear space you can get. Part of the difficulty in weaving the seat is that the sea grass is very bulky, and to avoid splicing more than necessary it is best to work with as long a piece as you can, which means you are passing a huge ball of rope over and under the chair. Fortunately, the seat does not have to be super tight to be strong and comfortable, and that fact makes weaving the seat a lot easier.

I purchased Standard #3 (6⁄32") sea grass in 250’ rolls. Start the front-to-back weaving first. It’s a good idea to tie the grass to a chair leg to start, and then begin to weave over and under the back and front frame pieces in a figure 8 pattern. Hand tighten front to back every 3 or 4 rows – though not too tight, as it will be too difficult to thread through the cross over (side-to-side) pieces later. A bit of looseness won’t affect the strength, look or comfort of the finished seat, but even so, getting the correct firmness is a bit of an art. Push the grass together laterally every four or five rows to keep it looking solid. Weaving the seat uses a lot of rope; one circuit is about 40 (generous) inches, and with 64 circuits on this chair, that is about 220 feet of rope. I am being very generous with the lengths here because, while sea-grass is generally very strong, it occasionally has weak points and an unexpected break while doing a bit of tightening can add a couple of feet to the required length after splicing. A roll of sea grass is about 250'. Don’t measure out and cut a 220 foot length – it’s better to make as big a bundle as you can handle, perhaps ⅓ or ¼ of the total. Try to strike a balance between ease of work and number of splices. Don’t worry about splicing if you haven’t done it before; just open up spaces between the braids and thread the piece to be attached back and forth for about a foot and test for slippage by pulling – when you can’t pull them apart you have spliced the two ropes. Of course, make sure your splices occur on the underside of the seat so you can’t see them.

Once you have completed the front-to-back weave, you will have two loose ends (the start and the finish) at opposite sides of the seat. These can be left tied to a leg until the cross ropes are in, and then they can be tied off to them.

Once the seat is done you can start with the side-to-side pieces. I used two separate pieces, one piece for each pair of holes. One trip around the seat is about 48 inches and you need four circuits for each hole; so that would be two pieces of about 16 feet each. I also add another four feet to each piece to accommodate any splicing that might be done in case of a break We all know it is easier to snip off a few extra feet at the end than to come up a foot short and have to splice. This is not the time to be frugal! The result is that you start with two 20-foot pieces of rope.

To start, tie a large knot in the grass or tie it to a small piece of wood to prevent it from passing through the side hole, but leave a 6" to 8" tail to tie off later, and begin the threading from the inside of the seat frame. The figure 8 weaving you did back-to-front definitely makes it tricky to thread through the side-to-side pieces because you have little room to work with. The rope has to pass through the ‘V’ tunnel made where the front-to-back rope crosses itself and this is tight. (Only one pass of each circuit needs to pass through this space, the return pass can just go across the bottom of the seat if you like.) As the drilled holes in the side frame begin to get busy with sea grass after a couple of passes, it can be difficult to push the rope through them. One solution is to wrap some soft but stiff wire round the end of the rope and use this to thread both down the tunnel and out the hole; then you can pull the grass through the hole a bit more easily. Once you have the two side-to-side sections done, you can begin to tighten them more seriously, by pulling them. When you are done, you should have two pieces of rope facing each other, and they can be spliced together as tightly as you can.

At this point you will still have two loose ends (tied off) that you left after weaving the seat. Pull these tight and splice them in to a parallel piece where they lie, or you can tie them off to the cross pieces that lie perpendicular to them.


grassseatchair_1
Rope tied off

grassseatchair_2
Rope passed through seat frame

Finishing
I used a Russet Amber aniline water stain followed with several coats of Tried and True semi-gloss varnish oil (leevalley.com). The stain seemed to virtually disappear as it dried, but the application of the oil brought it to life beautifully. You could also finish this chair with varnish or polyurethane.

I never tired of working on this chair, and every time I see it in our house, I get a thrill. If you choose to make one (or a set of six), I hope you will not only think it is as beautiful as I think it is, but also know that you have a small but important piece of western design history in your home.