Cut the template to a fraction over its fi nished size and sand back the edges

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Ethelbert Barker
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I PROJECT Oval coffee table BY DUNCAN ROSE An oval

coffee table she wanted without success, so she

The brief was for a low oval table supported by a

$the template to a fraction over its fi nished size$ and sand back the edges Rub-joint the cherry

together securely 4 5 6 Once the glue has dried

chisel 20 The Woodworker January 2010 www.

1 I PROJECT Oval coffee table BY DUNCAN ROSE An oval commission Working with wood allows you to turn ideas into reality. I had a customer recently who had hunted for the coffee table she wanted without success, so she asked for my help. The brief was for a low oval table supported by a central column, with little ornamentation. Less is more sometimes! Draw the ellipse profi le on a sheet of MDF using the pin and string method (see overleaf) Cut the template to a fraction over its fi nished size and sand back the edges Rub-joint the cherry boards that make up the top and clamp them together securely Once the glue has dried hard, trim off the squeezed-out glue with an old chisel 20 The Woodworker January and sand the top fl at. I m using my belt sander fi tted to a sanding frame Use the template to mark out the oval and rough-cut it to shape on the bandsaw

I started with the dimensions she specifi ed, and presented several CAD drawings so she

She wanted softened edges to the top, and four legs splayed asymmetrically to give more

This makes the job a little more diffi cult, but it looks better aesthetically and

I also showed her some fi nished wood samples, and she picked North American cherry (Prunus

This is an attractive, fi ne-grained wood that s easy to machine and is also good for

Yesterday s back Recent press coverage has suggested that yesterday s classic furniture is

This coffee table is in the style of Ercol, a company founded in 1920 in High Wycombe by

Ercol s design ethic was (and is) similar to that of the Shakers.

Quality was very, very high and the aim was to produce pieces that were beautiful and

2 I started with the dimensions she specifi ed, and presented several CAD drawings so she could select her preferred leg and column styles. She wanted softened edges to the top, and four legs splayed asymmetrically to give more stability than the usual three legs could provide. This makes the job a little more diffi cult, but it looks better aesthetically and certainly adds to the stability. See fig 1 overleaf for details of the construction. I also showed her some fi nished wood samples, and she picked North American cherry (Prunus serotina). This is an attractive, fi ne-grained wood that s easy to machine and is also good for turning. It glues well and gives an excellent smooth fi nish. Yesterday s back Recent press coverage has suggested that yesterday s classic furniture is enjoying a renaissance. This coffee table is in the style of Ercol, a company founded in 1920 in High Wycombe by Lucian Ercolani to make furniture in solid wood, and which is still in private hands today. Ercol s design ethic was (and is) similar to that of the Shakers. Every single piece was to be useful. Superfl uous decorative detail was non-existent. Quality was very, very high and the aim was to produce pieces that were beautiful and affordable. Making a start My fi rst step was to make a template of the exact oval top profi le. I drew an ellipse outline on a sheet of MDF using the pin and string method, photo 1. See the panel overleaf for full details of the geometry involved. I then rough-cut the template to within a few millimetres of its fi nal size and sanded it back to the line, photo 2. The Woodworker January

I PROJECT Oval coffee table Fig 1 Front elevation End elevation OVAL

Top 1 940 500 22 Column 1 275 66 66 Rails 2 376 32 22 Leg blanks 4

View from bottom 7 8 9 Then pin the template to the top and cut the

over the top edges with a bearing-guided cutter Finish the rounded

up the column blank by laminating together three 22mm thick cherry

com Turn the column to the two diameters shown in the drawing on page

3 I PROJECT Oval coffee table Fig 1 Front elevation End elevation OVAL TABLE CUTTING LIST All dimensions are in millimetres Part Qty L W T Top Column Rails Leg blanks You will also need a small quantity of 14mm hardwood dowel View from bottom Then pin the template to the top and cut the profi le cleanly on the router table Remove the template and round over the top edges with a bearing-guided cutter Finish the rounded edge to a smooth curve with some careful hand sanding Make up the column blank by laminating together three 22mm thick cherry blanks 22 The Woodworker January Turn the column to the two diameters shown in the drawing on page 25. Leave the top square Prepare a paper template with 60 and 120 angles to mark the leg positions

A Ellipse plot 398 398 500 All measurements in millimetres 940 DRAWING ELLIPSES You can draw an ellipse in several different ways.

The pin distance is calculated as follows: Pin separation = (w² - h²), where w is the longer diameter of the ellipse and h the shorter diameter.

You ll find the function on most calculators For this project, where the width and height are 940mm and 500mm respectively, the pin separation works out to 796mm.

Tie a piece of string around the two pins and fit the tip of a pencil inside it. Alter the length of the loop until the pencil lead just touches the tip of the vertical axis at A.

4 A Ellipse plot All measurements in millimetres 940 DRAWING ELLIPSES You can draw an ellipse in several different ways. I used the pin-and-string method with its simple formula that determines the pin separation for a given size of ellipse. Centring this measurement on the width axis gives the pin positions. The pin distance is calculated as follows: Pin separation = (w² - h²), where w is the longer diameter of the ellipse and h the shorter diameter. You ll no doubt remember the square root symbol from your schooldays! You ll find the function on most calculators For this project, where the width and height are 940mm and 500mm respectively, the pin separation works out to 796mm. First draw the width and height axes of the required ellipse as two lines intersecting a 90, as shown in the drawing. Next insert two pins, each 398mm from the centre point along the width axis. Tie a piece of string around the two pins and fit the tip of a pencil inside it. Alter the length of the loop until the pencil lead just touches the tip of the vertical axis at A. Keeping the string loop taut, draw the ellipse out by moving the pencil round the curve in a clockwise direction. 13 Make a box jig with a slot in the top to hold the column while you rout the dovetails 14 Align the column with each marked leg position in turn positioned uppermost in the jig Preparing the top Next make up the panel that will form the table top. I converted four boards of 26mm sawn cherry, fi nishing them 22mm thick. To keep the top stable, arrange the boards with alternating end grain, and place any unattractive surfaces on the underside. Rub-joint the boards with glue and clamp them together. I used a combination of sash and four-way pressure clamps, photo 3. Each end joint was kept aligned with a clamp. After about an hour, remove any excess glue using an old chisel, photo 4. Once the work is totally dry, sand the top smooth, photo 5. Cutting the oval I cut the oval profi le on the top using the template and a bearing-guided straight cutter in my router table. First use the template to mark the profi le on the top, and rough-cut it on the bandsaw to within a few millimetres of the line, photo 6. Then pin the template to the underside of the top and use the cutter in the router table to make a clean cut of the profi le, photo 7. Routing the end grain round the points of the ellipse can tend to scorch the wood. You can minimise the risk by using a moderate cutter speed, taking multiple smaller cuts and keeping the work moving while you re cutting it. Once you re happy with the fi nish, remove the template and round over the edges on the table top. I used a 9.5mm radius bearing-guided round-over cutter in the router table, photo 8, and fi nished off with some careful hand sanding, photo 9. Shaping the column The column is turned from 66mm square section cherry. I made the piece up by laminating three 22mm thick pieces of colour-matched stock together with PVA glue, photo 10. The table top will be attached to the column using a pair of parallel top rails. Mark the extent of the column top section, keeping it square to accept the top rails. Then turn the rest of the column to the 15 Cut each socket in the leg using fi rst a straight cutter, then the dovetail cutter 16 Cut a notch in each side of the square top section to accept the two top rails The Woodworker January

I PROJECT Oval coffee table 17 18 19 Cut slotted holes in the two top rails to take the fi xing screws for the table top Glue and temporarily screw each of the top rails to the notches in the column

securely while cutting its dovetail Glue the leg dovetails into their sockets. I clamped them in opposing pairs dimensions shown in fig 2.

Cunning dovetails The legs attach to the column using the traditional interlocking dovetail method.

I created a paper template and used it to mark the 60 and 120 positions on the column, photo 12. and clever jigs Cut the four dovetail sockets on the column, either by hand or machine.

The box grips the column securely when it s held in the bench vice and provides a fl at surface to guide the router while cutting the sockets.

Cutting in stages With the column in the jig, align the leg positions with the column leg marks uppermost, photo 14.

5 I PROJECT Oval coffee table Cut slotted holes in the two top rails to take the fi xing screws for the table top Glue and temporarily screw each of the top rails to the notches in the column Remove the screws and drill out the holes to accept pegs of 14mm diameter dowel and sand them smooth using a combination of power and hand sanding I made another simple jig to hold each leg securely while cutting its dovetail Glue the leg dovetails into their sockets. I clamped them in opposing pairs dimensions shown in fig 2. The shoulder between the 66mm and 62mm diameter sections will hide the joint between the top of the leg and the column, photo 11. Cunning dovetails The legs attach to the column using the traditional interlocking dovetail method. Mark the leg positions on the column base with careful reference to the square column top (see fig 2 again). I created a paper template and used it to mark the 60 and 120 positions on the column, photo 12. and clever jigs Cut the four dovetail sockets on the column, either by hand or machine. I chose the latter, as I like to make jigs for repetitive tasks. This jig is a simple four-sided box with a slot cut in the top to give access to the router cutter, photo 13. The box grips the column securely when it s held in the bench vice and provides a fl at surface to guide the router while cutting the sockets. The top edge of the jig guides the router with the help of a pair of router side fences. A block on the jig top will stop you cutting into the column shoulder accidentally. Cutting in stages With the column in the jig, align the leg positions with the column leg marks uppermost, photo 14. I initially roughed out the four dovetail sockets with a 6mm straight cutter, followed by a single pass with the dovetail cutter to create the fi nal shape, photo 15. I also used the jig to cut a fl at along the top of the sockets for the leg shoulders to buttt against. Adding the top rails Next, cut two notches in the square top section of the column, photo 16. These help to locate and strengthen the top rail joints. Cut and shape the two rails. Then use the router to cut slotted clearance holes in them for the screws that will attach the top, photo 17. The slots allow for any wood movement across the grain due to humidity changes. Glue the rails to the column. Drill clearance holes in them and drive in a couple of screws to keep each one in position while the glue dries, photo 18. Driving the dowels When the glue has set, remove the screws and enlarge the holes to accept lengths of 14mm diameter dowel, photo 19. Spread glue on the dowels and inside the holes. Then drive the dowels in immediately, photo 20, before the water in the glue can swell the wood. Use the bench vice as a clamp to force the last portion of the dowel into place. When the glue is dry, you can either trim the ends of the dowels fl ush or leave them to project as a feature of the design. Shapely legs Prepare the four cherry leg blanks and mark each one with the required profi le. I used a paper drawing of the leg, fig 3, and transferred the outline to each blank with carbon paper, photo 21. Make sure the grain direction runs the along the overall length of the leg for maximum strength. I was going to make an MDF template and use the bearing-following method to rout them to shape. But I felt somewhat less than safe handling the small legs while cutting end-grain using my current router table set-up. So I did the job on the bandsaw instead. Cut out the legs almost to the marked profi le, photo 22, and sand them smooth back to the mark, photo 23. Traditionally, pedestal table legs are tapered slightly towards their feet. This feature isn t really necessary on this table, but if you want it now is the time to do it. Routed dovetails Next, cut the leg dovetails to fi t the column sockets. Again this can be done by hand or machine. I used the router with a simple support jig held in the bench vice. The jig allows the work to be securely clamped 24 The Woodworker January

20 21 22 Apply glue to the dowels and inside the holes.

to transfer the outline of the leg profi le to each leg blank Cut

56Ø 66Ø 142 275 5 5 56Ø 26 Use the leg assembly to mark the

22 156 View from bottom Fig 3 200 233 83 All measurements in

6 Apply glue to the dowels and inside the holes. Drive in the dowels before the wood swells 32 Fig 2 Use carbon paper to transfer the outline of the leg profi le to each leg blank Cut the four legs out to almost their fi nal size on the bandsaw Ø 66Ø Ø 26 Use the leg assembly to mark the positions of the fi xing screws and drill pilot holes 73 62Ø View from bottom Fig All measurements in millimetres 11 All measurements in millimetres The Woodworker January

I PROJECT Oval coffee table 27 28 29 Apply three coats of Osmo hardwax oil.

against a vertical surface, while also providing a stable horizontal surface for the router, photo 24. Dry-fi t the legs to the column and check their fi t.

Final assembly Now you can glue the legs to the column. I found that a cheap artist s brush worked well for spreading the glue evenly inside the column sockets.

Once the glue is dry, repeat the process to attach the other pair of legs.

7 I PROJECT Oval coffee table Apply three coats of Osmo hardwax oil. Wipe off the excess and sand between coats After 24 hours, apply some paste wax with a synthetic pad and buff it up Oil and wax the leg assembly in the same way, then reattach it to the table top against a vertical surface, while also providing a stable horizontal surface for the router, photo 24. Dry-fi t the legs to the column and check their fi t. Number the legs and corresponding sockets to avoid fi tting problems later. Then remove them, round over their edges and give them a thorough sanding. Final assembly Now you can glue the legs to the column. I found that a cheap artist s brush worked well for spreading the glue evenly inside the column sockets. I glued the legs in place in opposing pairs. They were clamped tight to the column using pairs of blocks on each leg, which were then pulled together, photo 25. Once the glue is dry, repeat the process to attach the other pair of legs. Centre the leg/rail assembly on the underside of the table top and mark through the slotted holes in the rails to indicate where to drill pilot holes for the fi xing screws. Drill the holes using a depth stop so you don t overshoot, photo 26. Drive in the screws I used 50mm No 10 roundheads to check that everything locates correctly. Then unscrew the top again, ready for fi nishing. Oil and wax Keep the top clear of the workbench during fi nishing by nailing three or four pins into the underside. I applied three coats of satin Osmo Polyx rapid oil with a brush, then wiped off any excess with absorbent paper, photo 27. This product gives a quickdrying, low sheen and durable fi nish. Sand gently between coats with fi ne wet-and-dry abrasive to keep the fi nish smooth. Invert the table top on fabric pads and treat the underside, then apply thrtee coats of oil to the leg assembly too. After allowing the oil to harden for 24 hours, apply a coat of paste wax using a synthetic pad, photo 28, and buff it up with a clean, dry cloth. Finally reattach the leg assembly to the table top, photo 29, and the job is done. FURTHER INFORMATION Osmo Polyx hardwax oil Osmo UK The Woodworker January

Gambling queen. This tournament-sized backgammon. I PROJECT Backgammon table

Gambling queen. This tournament-sized backgammon. I PROJECT Backgammon table I PROJECT Backgammon table BY DUNCAN ROSE Gambling queen This commission was placed by a customer who knew exactly what he wanted in appearance, dimensions, functionality and style; a backgammon table