Highlighting shadow and texture: Making a wall light

Words and photos: Andrew Potocnik
Illustration: Graham Sands

Many of the pieces I make rely on the fall of light and how forms and the texture inherent to wood can be be highlighted. Receiving a prompt to make a light finally hit a trigger to get the ball rolling.

A few simple sketches and notes were enough to keep my mind ticking over a number of days, maybe weeks. Then, as the idea evolved, I needed to source suitable material and arrange it to create the base, and then work out how to apply the texture which was to be integral to the overall effect of the piece.

All of this sounds fancy, but as a maker of one-off pieces who is not reliant on constant income derived from production work, I have the freedom to explore ideas, and in turn write about what I learn as I make. After all, I spent most of my working life teaching wood in a secondary school environment where problem solving was part of the day-to-day aspect of helping students achieve success in the projects they conjured up...or stuffed up!

So where to begin? Material! Searching through my stash of bits and pieces I cannot bear to throw out, along with bits I pick up as something of a bowerbird, I realised the oregon stair treads I’d scored from a neighbouring nature strip would tick all boxes – size, grain, available and free!

I first drew a full size sketch (fig.1) on some packing cardboard, something I don’t often do, but in this case in order to establish the overall dimensions my lathe could handle, and to ensure I had suitable material on hand.

Fortunately, a couple of trial cut pieces showed that when machined clean, there would enough for this project (photo 1). I cut a series of wedge-shaped pieces which were planed straight and smooth along their edges, then glued together with two-part epoxy glue using a simple rub joint (photo 2).

I was conscious of the fact that my machining wasn’t perfect, so the glue would act as a gap filler, and knowing that these joints would be subjected to heat later in the making, I couldn’t use thermo setting glue, which could loosen and de-laminate.

Once assembled, I cut the disc to a circle on the bandsaw, and attached it to a carrier fitted to a faceplate (photo 3), which would be fitted to my lathe. Turning a disc of about 750mm requires a solid base so the relatively thin 35mm disc had ample support so it doesn’t flex as it’s turned.

Fitted to the lathe, the outside edge of the disc was trimmed to a true circle, the face flattened and then trimmed down to an interior thickness of about 15mm (photo 4).

To achieve the final textured surface I was after, I made sure this tapered area was as flat as possible, so I checked it regularly with a steel rule (photo 5).

The centre of the disc needed an opening with straight sides to accept a half doughnut shape form, so a beading tool was used to leave a small shoulder at the base of the cut (photo 6).

To begin the half doughnut, a 75mm thick x 270mm diameter x disc of oregon was mounted to my lathe and turned down, leaving the centre stub in place. The pencil line you can see in photo 7...

shows the top and middle of the curve, which was gradually refined and sanded smooth (photo 8).

You can also see that the centre area was trimmed to a become a tenon that enabled me to reverse the form (photo 9), and mount it in a scroll chuck so I could shape the underside of what is really just a hollow sleeve

Once the base was trimmed to size, it was time to test how well it fitted into the oregon disc (photo 10)...

before the sleeve was parted free of the carrier and its exterior surface sand blasted to make the wood’s growth rings stand out (photo 11).

A couple of coats of Black Japan were applied to darken the exterior (photo 12), while white paint was applied to the inner portion to help reflect light out onto what would be the textured surface of the oregon disc.

As I’m not a licensed electrician, I used a strip of LED lights which can be bought as a complete set- up with a power pack and all wiring ready to plug in. The meter long strip allowed me to wrap it around the sleeve twice (photo 13). The black socket plugs into a wire that travels to a transformer which is then plugged into a power point. Too easy.

To begin routing the face of the oregon disc, I first needed to make a sled which would allow a small laminate trimmer to travel in a sweeping motion (photo 14).

A V-shaped cutter would then create a groove that starts as a narrow point, gradually entering the wood deeper end making the groove broader, before narrowing and exiting the board (photo 15). The sled consists of two 12mm thick pieces of MDF, with a 3mm thick section glued in between. A centre line and a couple of extra marks on a strip of masking tape enable accurate positioning of the sled on the board. 

After what seemed an eternity of positioning, clamping, routing, and then repeating the process over and over again, I had numerous grooves radiating out from the centre of the board to give some interesting grain patterns (photo 16).

To reduce the strong circular appearance of the disc, I cut a series of lines a small distance in from the edge on my bandsaw (photo 17).

Returning the assembly to the lathe, each of the cuts was widened and rounded to run into the routed grooves using a rasp (photo 18). This portion didn’t need to be smooth as the next step was to scorch the edges and face of the disc. Using a butane gas torch, the wood was burnt but I didn’t apply too much heat so the disc would not buckle, or the glue soften and delaminate.

The scorched surface was then brushed back with a stiff bristled nylon brush to expose the now highlighted grain and growth rings (photo 19). I didn’t want this surface to darken, so it was left bare without a finish.

The final component of the light was a disc that was to fit into the middle of the doughnut sleeve. A piece of 19mm thick jarrah was mounted on the lathe and turned to match the opening in the sleeve. Vernier calipers ensured an accurate fit (photo 20).

Lastly, I created some beads, flats and a couple of rebates, which were filled with gold leaf and cyanoacrylate glue (photo 21). Two coats of oil finish were applied before removing the disc from its carrier. The three components were then assembled with a hook added to the back, and the project was complete. Now to connect the wiring, turn on the switch and see what happens... And I was a happy vegemite!

First published in Australian Wood Review, issue 124, September, 2024.

Andrew Potocnik is a Melbourne wood artist, teacher, author and regular contributor. See www.andrewpotocnik.com