Monday 9 July 2018
A few years ago I was asked to make a trophy for the Small Business Awards in my home town and I instantly thought of a technique I had seen in a very early issue of Woodturning magazine. This technique involved turning a pattern of concentric circles on a board of timber, cutting into strips and reconstructing to create a 'randomly uniform' pattern. I remembered that some of the examples had steel rod to space strips of timber from the main body â€“ similar to the piece featured in this article.
The trophy was a smaller version of the piece shown and instead of the added end sections, I attached a base with two steel rods. This led to me experimenting with other variations and soon I had several pieces decorating my lounge wall.
The original pieces I saw were made from mahogany (Khaya ivorensis) with only turned pattern for decoration. I experimented with different timbers and used embossing powders to add another dimension to the piece. The embossing pens, powders and heat gun were left over from my card making days so it was useful to be able to use them on my turnings. Other decorative techniques could be used to create your own unique wall art. I still have a selection of sketches for further pieces, which I am hoping I will someday find time to make.
For the main body of this piece you will need to prepare a square board of ash (Fraxinus excelsior) that measures 342mm wide x 355mm long x 19mm thick. The piece I prepared was made from three strips glued together. I suggest using an orbital sander to work through 120, 240, 320 and 400 grit abrasives until you have the desired finish. For the end pieces you need to prepare two strips of timber 42mm x 395mm x 19mm thick. Next, sand the piece to the required finish, spray with ebonising lacquer and then you can put it to one side. These will be attached to the finished main body using steel rod a little later in the process. Mount the square board on the lathe. I used a vacuum chuck but you could also attach a sacrificial chucking point to the back of the board using either Cyanoacrylate adhesive or hot melt glue. Starting at 20mm in from the outer edge, draw five concentric circles approximately 32mm apart
Use a 10mm fingernail-profile spindle gouge to create beads on the marked concentric circles, but take care to make them all the same width and depth otherwise you will throw the design out. Alternatively you could use a bead former for this process – the choice is yours
The next step is to take a 2mm parting tool and create a flat section at either side of the beads you have made
Sand the beads but take care not to spoil the profile. Here I folded the abrasive to create a triangular section the same size as the bead. This enables you to sand more effectively. Work through grits 180, 240, 320 and 400
After covering the lathe with a dust sheet or something similar, spray the timber with ebonising lacquer
Once dry, cut coves between the beads and make sure the flat sections cut earlier are of a uniform width. Use a 6mm (1â„4in) standard grind bowl gouge for this. Sand the coves working through the grits as before, taking care not to damage the ebonised sections, and coat the clean timber with acrylic sealer to protect it from the next process. If you are using a vacuum chuck then take care not to cut these coves too deep
Using an embossing pen â€“ available from craft shops â€“ draw around the flat section next to the bead. It is advisable to do half a circle at a time so the embossing ink does not dry before you are able to coat with the embossing powder
Coat with silver embossing powder and shake off the excess. A soft bristled brush is useful for removing the powder residue
Use a heat gun to heat the embossing powder until it bubbles
When all the flat sections have been embossed you can cut the board into strips. Firstly, cut through the original glue joints and then divide the sections evenly. I cut 12 strips from this size of board
At this stage use a thicknesser to clean up the cut edges
Lay all the pieces in the correct orientation and start to move them around until you have achieved the pattern you are looking for
For the positioning of the steel rods take the two end pieces and mark the centre, measure 50mm to the right and 50mm to the left of centre and draw pencil lines across both pieces using a 90 degrees square. Repeat this process for the larger end sections prepared earlier
Set a mortise gauge to half the thickness of the timber and make a mark on each of the reference points
Use an engineering vice to hold the timber square and drill a 5mm hole to a depth of approximately 12mm. Using a brad point drill bit here will make the drilling position easier to align
Use Titebond to glue the strips together. Here I am using a jig to aid with the gluing process. I have attached two lengths of wood to a board of MDF to create a raised 90° corner. Use a piece of newspaper to prevent the strips from being glued to the jig
Clamp strips of timber across to the top and bottom to stop the pieces from lifting when they are clamped tightly together. Use a damp cloth to remove any excess glue and leave to dry. Drill a hole large enough to receive a brass wall hanging bracket and screw in place
Cut four 5mm (3â„16in) diameter steel rods approximately 50mm long. Glue them into the holes drilled in the main body and the longer length end strips. Epoxy resin works well for this. Use spacer blocks to ensure that the gaps between the board and end strips are of a uniform size
After several coats of finishing oil the wall art is ready to hang