|Live edge table|
Publish On 08-03-2009 , 23:30
Live Edge Table
This table is being built for a new house set in among a lot of trees. The owner's requested a natural or organic design that was not too formal. I had saved two pieces of this ambrosia maple with the live edge for almost two years and this seemed like a perfect piece to design a small, hallway table around.
Below is the initial sketch I made of this table. Because of the live edge, I wanted to incorporate some curves in the uprights and the bottom stretcher. There will be a through tenon with a tusk wedge on the stretcher and the uprights will also be through tenons into the top with wedges. Some of the final details have not yet been decided. On pieces like this where there are no absolute dimensions and details, I often make decisions as the piece progresses. The approximate size will be 48" W X 14" D X 32" H.
Ambrosia maple is a regular maple tree (in this case, hard maple) that has been invaded by the Ambrosia beetle. The beetle bores holes in the tree while it is still wet and carries in a fungus. The fungus is used as nourishment for the beetle, but it also causes the dark streaking around the small, bored pin holes. The dark streaks set against the lighter maple heartwood gives an interesting color contrast. The kiln drying kills the beetles and fungus.
A live edge plank means that the outside (bark) edge of the tree remains intact. How much remains is up to the builder. Some species do not hold the bark well and it easily falls off, leaving a wavy edge with the sapwood. Often times, as in the case of cherry, the contrast of the light colored sapwood and the darker heartwood, gives a nice "natural" look. In the case of this Ambrosia maple, the heartwood is light, but with cherry colored streaks. Therefore, the base for this table will be made from cherry.
Flattening the top
Because of the width of this plank (approx 14") it could not be flattened on my 8" jointer. I could have ripped it in half, jointed the two pieces, then edge glued it, but I did not want a seam. Therefore, it is necessary to flatten one side with hand planes then run it through the planer to flatten the other side. Using winding sticks and a straight edge, mark those areas that are high. Start with a scrub plane and working at a 45 deg. angle to the grain, take off the high areas. Moving to a #5 jack plane, and still skewing the plane, clean up the plane marks. This plank has some "squirrly" grain because there is a lot of wave in it, so I finished up with a #5, low angle jack plane going with the grain to avoid tearout.
Because the live edge on the top is slightly wavey and naturally chamfered, I thought the other three edges should have a look to compliment this edge. Using a block plane, I undercut (reverse chamfer) each of the edges starting about 1/4 " down from the top. I then put a very small chamfer on the top edge. This result has three facets on the ends and back edge which I believe looks more appropriate than a square edge. (If possible, use a low angle plane on the ends). If the plane is sharp, there is no need to sand. The facets from the plane will add to the organic look and the oil will penetrate the wood better .
Each plank leg will be approximately 12" wide, therefore I need to edge glue two pieces together. As I said earlier, cherry is my choice for the base to this table as it will coordinate nicely with the reddish streaks in the maple top. I think one of the most important parts in designing pieces is the matching of wood when edge gluing. Because most of us don't have the luxury of finding 12" wide cherry (especially if you need to take off the light colored sapwood), edge gluing is necessary. It was helpful that all the cherry came from the same tree, but it is still important to take the time to match color and grain at the seam. Below are the rough cut pieces layed out and marked for the plank legs and stretchers.
And below are the legs after flattening and squaring the edges. They are now ready to glue up. Notice the markings to keep the grain alignment and the proper pieces together.
Joinery for Legs
Once the legs have been glued up, cut them them square to length and width. When determining the length, don't forget there will be tenons on both ends for the feet and into the table top. Now, layout the locations of the mortises in the bottom of the table top. Don't forget the legs will be shaped later so leave wood at the edges for removal.
The mortises into the table top and legs are most easily cut with a router set up with a fence and are cut about 5/8 " deep. The mortise in the center of the leg goes all the way through and will accept the tusk tenon. I also cut the mortise into the foot blanks and through the ends of the stretcher, but used a horizontal mortiser for this operation as it is quick to set up and ideal for this. Use a chisel to square up the corners of the mortises.
Because the tusk tenon will wedge the through tenon into the sides of the legs, it is necessary to chisel a slight angle into this mortise. To do this accurately, it is necessary to use a small jig as in the picture to angle the side wall to about 5 degress. The tenon will then also be cut to this angle and fit snugly into mortise. The picture shows the angle marked on the cheek of the through tenon.
This detail of the tusk tenon shows a possible shape. As long as it fits well in the mortise, the shape of the wedge itself can be varied to your taste. The wedge is made from bubinga to have some strong contrast to the cherry leg.
Below is a dry assembly of all the parts. It is clear that the leg design changed somewhat from the original sketch. As I progressed through the shaping of the legs, it seemed better to have a more simple shape to match the overall organic scheme. You can also note the chalking of the feet. I wanted to see the rest of the piece before deciding on the foot shape.
Below is the finished table. As you can see, there were some changes in the design as I progressed through the piece. The plank legs do not have the wedge cut from the center as in the drawing. I wanted to put a stretcher under the top at the top of the legs and center it, so this prevented the first design. I also did not run the legs through the top with tenons. I decided the grain of the top should not be disturbed with end grain from the legs.
The table has 5 oil/varnish coats of varying ratios of tung oil/urethane.