Hybrid Box archive
Tuesday 30 November 2010
Inspired by various techniques, Andrew Potocnik creates this stunning hybrid box which can be left natural or coloured
Attending a collaborative event several years ago, I witnessed techniques employed by a range of woodworkers ranging from engraving, to painting, to turned forms. Impressed with each technique I returned home and engraved, turned and painted until I came up with a combination that made me feel I had combined other people's techniques into something I felt was my own, resulting in my "hybrid bowl" series. Since then I've tested variations in dimensions, sizes and decorative techniques until I created something I felt was my design, not just a copy of other people's work.
Working on another series of 'hybrids,' a new development dawned on me - converting the bowl into a hybrid box.
The initial concept was of two bowls facing each other top to top to form a mirror image, almost like a clam. This looked great as a form, but it wouldn't work as a box, because the overall form would be too heavy once picked up and opened. The base needs to be quite hollow and the lid needs to be light when you lift it from the box. No matter how you view the final form, there are times when initial inspiration will not allow the final design resolution to work. There needs to be negotiation between that imagined in the "minds eye," method of creation and how the final item feels and functions. There are many things to think about, and many problems that arise are only resolved through trial and error. Making the piece over and over, combined with careful reflection, should lead to a fully resolved final product.
Tools used Round-nosed scraper, French-curve scraper, domed-end scraper, granny-tooth scraper, 'V' point scraper and bowl gouge
Firstly, take two blanks of red gum (Eucalyptus camaldulensis). Press the bandsawn blank against a scroll chuck using the tailstock to hold it secured so it can be roughed down. In effect, this is a pressure chuck but the jaws of the chuck need to be extended as far as they can to spread the pressure load over the blank. The tailstock has to be absolutely secure with no creep along the bed, or the hold pressure will fail
Next, turn a spigot on the tailstock end of the blank then remove the blank. Reverse it and grip the spigot in your scroll chuck, and clean up the exposed face of the blank
Use a pencil to mark out the outer edge of what will be the hollowed out section. I also like to create a break between the hollowed section and the area that will be decorated by leaving a small, slightly angled band, so the outer edge of this part will need to be marked, too. Once marked out the initial hollowing can be done with the 12mm (1/2in) bowl gouge, followed by a round-nosed scraper to refine the interior form of the bowl
Once the hollowing has been done the outer band is defined with a sharp 'V' groove cut with the long point of a point scraper or skew chisel. To check the angle quickly I use the edge of my scraper to ensure the edge sits below the overall outer rim of the bowl. Once happy, sand it and the hollow to a fine finish, ensuring to retain the crisp detail. If not, you run the risk of creating forms devoid of definition that simply curve from one plane to another
With dimensions, angles and sanding out of the way you can begin to add texture to the rim of the box using a rotary burr. I use a ball-ended cutter, but by using different shapes of cutter you can create various patterns. I used to use a hand-held Dremel but I now have the motor unit suspended with a flex-drive attached, so it is lighter and easier to manipulate. To get rid of the furry frayed bits of wood left by the burr, clean the surface with a brass wire brush
To complete the underside of the box I like to use a jam chuck. To make one, fit a blank of the same wood as the bottom on to a scroll chuck. The jam chuck then becomes the lid of your box. Once the jam chuck blank is fitted on the chuck mark the size of the tenon needed - this will eventually be the mating spigot of the box lid - and turn the waste wood away with a gouge and then trim it to the exact diameter using a homemade 'granny tooth' scraper. The idea is to make the tenon slightly flared so the box can be wedged into place. The key is to not make the base of the tenon so wide that the rim of the bowl cannot push tight against its base and, in turn, run truly
Use a bowl gouge to remove the bulk of the waste timber and clean up the outer edges of the bowl blank and the jam chuck. You can bring up the tailstock for support for this part
Use a bowl gouge to shape the bowl's exterior and removal of the spigot. Refine the form with a scraper until it sweeps from the edge down to a base of about 30mm (1 1/8in) diameter...
..then where the spigot used to be, create a slight hollow and use a scraper to refine it
Incise a 'V' cut about one-third of the way down the outside curve. Use a 'V' scraper to cut it. This is a definition line and a carved pattern is added up to this mark
Now use the rotary carving tool to carve a similar pattern to that previously cut on the top face. When completed, gently lever it free of the carrier with a chisel and add some padding so the tool will not mark the finished surface. Then, sand and clean up the piece and gently lever it off the jam chuck
Now use a bowl gouge to shape the meeting face of the lid. Don't remove the tenon previously cut for the jam fit, instead refine it with a point tool and create a hollow - as you did with the base form earlier. After shaping the hollow you need to cut a couple of 'V' grooves for decoration. Don't be scared to make these grooves bold, otherwise they'll just look like scratched afterthoughts and will serve little purpose
Sand the top face, hollow the spigot and then carve the outer rim of the lid
Now you can reverse chuck the lid by holding it in a jam chuck or in a set of jaws, but don't grip too tightly or you will mar the spigot. Bring the tailstock up for support and turn the bulk of the timber away and rough-shape the lid
Now refine the top shape of the lid. Remove the tailstock and use a scraper to finish the curve and add a 'V' groove - again, the point to which the carving will go. After this you can sand down to 320 grit. Some feel they should sand well beyond this grit, but unless you're working with incredibly dense timbers from arid areas of the world, you shouldn't bother. Bottom line: check the surface of your wood and decide whether you need to go finer
Now carve the piece up to the incised 'V' cut and then...
...use a bronze brush to clean up the fuzzy edges of the carved detail
To finish it off you need to apply a finish. I usually apply a tung oil-based product such as a Danish oil, but in this case, I have used a polyurethane-based product. I like the patterned effect. You can now alter this piece further by applying some colour
Once the oil/preciously applied finish is fully dry you can set about applying colour. I have found that Jo Sonja's paints work very well on wooden surfaces. Depending on your location and personal preferences, experiment with what's available in your neck of the woods. There are many products available and I continue to explore and refine those that suit me. To apply paint I use a flat broad brush followed by a sea sponge. Both should be available in local art supply shops
Painting the textured surface begins with laying down a base colour with a brush. I find it's best to begin with the darkest hue before working through to the lightest, which you'll apply least of later in the process
Next, you need to dapple the next colour on using a sea sponge...
...followed by another lighter hue of whichever colour you choose
The final application of paint highlights the high spots of the textured wood. Using my finger, I like to apply an iridescent paint to protruding surfaces of the carved surface which, in effect, takes the embellished surface back to where it all began, i.e. the carved pattern