Weekend Projects - Jarrah Burl Box archive

Friday 13 March 2015

Andrew Potocnik creates this charming lidded box with a contrasting lid and finial using a piece of jarrah burl

Gallery

It's difficult to let go of small pieces of treasured timbers, and sometimes even more difficult to find ways of converting them into a final project. Here I show how a small piece of jarrah (Eucalyptus marginata) burl spurred me on to create a lidded form where I constantly questioned how I could use other leftover pieces too good to throw away, and then challenge myself a step further in making a handle different to others.

This box came about as a personal challenge to convert a small piece of highly figured jarrah burl into a centrepiece that featured a contrasting highly figured lid of eucalypt burl.

To finish the piece I opted to turn a thin tapering handle, steam-bent to replicate the curve of the lid's upper form. To combine the box and lid, I turned a collar of timber similar to the lid which presented acouple of small challenges along the way.

STEP 1

The first step in this project is to cut an offcut of jarrah burl to a neat circle using the bandsaw ready for mounting via a three-jaw chuck. Next, cut a spigot, ready for the blank to be transferred to a more practical four-jaw scroll chuck. There are lots of other ways you can mount wood on the lathe, but use whatever mechanisms you have or adapt techniques you feel most comfortable using

STEP 2

Now it's time to turn the form and get the project moving along. I have an old three-jaw chuck that is welcome in times when I need something large to hold. You could simply turn the blank down between centres to suit any chuck you intend to use, but be sure to cut an angled tenon to ensure maximum grip for your chuck's jaws once the blank is reversed

STEP 3

Turn the overall form to shape paying attention to the outer shape and proportion of the inner opening, keeping in mind that a collar will later reduce the opening's size

STEP 4

Use a round-nosed scraper to undercut the form, but you may use any tools you're more comfortable with. The key here is to undercut the form and open up as much volume inside the container as possible, whilst not going through the sides

STEP 5

Once the interior is sanded - I work from 120 grit to 180, 240 then 320 grit - it's time to cut a recess that a collar will fit into. I use a 'granny tooth' scraper for this but you may find a skew chisel or a parting tool better. The key point is to ensure you have neatly cut shoulders and faces on the step you have cut otherwise the collar will not fit correctly

STEP 6

Next, you need to grip a blank of contrasting coloured eucalypt burl in another scroll chuck, ready for turning. To minimise waste, use heat-sensitive glue to attach a thin piece of burl to a sacrificial scrap block which is held in the chuck

STEP 7

Cut a small step into what is to be the underside of the collar, matching the opening that has been cut in the box. Once fitted in place, sand as much of the collar as you can to ease the process

STEP 8

Parted free from its carrier, now glue the ring into position, ready for its final shaping and sanding

STEP 9

To complete the box's base, prepare another carrier to match the inner diameter of the collar and apply double-sided tape around the tenon, allowing the box to be remounted in reverse

STEP 10

Next you need to turn away some scrap wood and shape and sand the underside of the piece with the tailstock supporting the wood

STEP 11

With the waste stub sawn away, relying on the grip of double-sided tape, use your left hand to support the box and gently turn away unwanted wood and create a concave surface. Beware: this is a small piece that requires little trimming so the tape does its job. Anything larger and I'd be using an alternative such as heat-sensitive glue or a chuck opened in expansion mode

STEP 12

For the lid of the vessel, take another piece of highly figured burl, again attached to a sacrificial carrier. Turn a tenon and the underside of the lid-to-be undercut so that it will not sit too high up from the body of the box. Sand the project through to 320 grit and remove from the carrier

STEP 13

Make the carrier into a jam-fit carrier using Vernier callipers and a granny tooth scraper to get just the right fit

STEP 14

Pressed into place complete the top of the lid of the vessel and cut a fine 'V' groove about 5mm inside the edge to create a border and a visual break in the surface. I used a skew chisel here, but a diamond pointed scraper could achieve the same result

STEP 15

To prise the lid out of the carrier use some padding - in this case worn out sandpaper - and a chisel. Work your way around the piece levering a bit at a time as the lid is quite thin and brittle

STEP 16

For the handle, turn a piece of dark desert timber so that it flares at the chuck end, almost like a trumpet shape, then sand and cut free. Dome the broad end with a skew chisel and then hand sand to remove evidence of how it was gripped

STEP 17

After filing and sanding two opposing flatter areas soak the handle in water and bend to shape using a luthier's bending iron. It's a form of steam bending and as the heat dries the wood out, it needs to be dipped in water, repeating the process until the wood becomes pliable enough to achieve the curve you're after. I use the heat given off by the iron as it cools to dry the wood. Leaving it just next to the iron, I can get on with the next stage

STEP 18

Turn a small bead and sand; this acts as a spacer between the handle and lid

STEP 19

Use a 1.5mm drill bit to create a small hole through the bead. You now get an idea of how small the bead is. Hold the drill bit in a pair of pliers

STEP 20

Drill a corresponding hole in the lid and handle and join all three with a 1.5mm brad and cyanoacrylate glue

STEP 21

The completed jarrah burl box should look like this


Briony Darnley

Tagged In:

Andrew Potocnik , Weekend Projects


Information

Time taken & cost:
Time taken: 5 hours
Cost: £16
Tools required:
Rolly Munro hollowing tool
Spindle roughing gouge
12mm gouge
Undercutting scraper
Skew chisel
Parting tool
Granny tooth scraper
Spear/diamond pointed scraper

Handy Hints

1. I turned a wooden bead for the spacer, but you can use any material. I have previously used glass beads, but you could try stone or any other material
2. With small fiddly items such as the lid, bead and handle, I like to finish all components before assembling them. They are hard enough to hold as it is, and it is even more difficult to get into nooks and crannies when they are assembled
.3 I like to use contrasting timbers for visual effect, but you could easily use one species or colour throughout the entire project
4. To glue the collar into place I take the work off the lathe, stand the chuck upright and place something heavy on the collar so it sits flat in its recess and bonds tightly
5. To give lids a bit of lift and definition, cut edges back on a slight angle rather than leaving them vertical. About 90 degrees to the top curve works well

Diagrams Click an image to enlarge