Three Legged Vase archive

Monday 18 May 2009

Steve Russell turns this lovely vase with three contrasting legs

Gallery

For a new challenge, try adding separate raised legs to your favourite designs. Most woodturners do this by turning an area on the bottom of the form in the shape of the feet they want and then carve away the waste areas, leaving only the feet on the lower portion of the form. You can experiment with different styles of feet, different numbers, as well as how and where the feet join the form.

Or you can take this one step further by experimenting with turning or carving feet from a contrasting timber and attaching them to your hollow form in some way. This approach is more complicated than turning the feet from the same timber, but it does allow you to explore different colour combinations and how they might affect the final form. Freeing the feet or legs from the primary form also allows you to explore different ways of making them. For example, you could turn them on the lathe, bandsaw them out and carve them, or perhaps turn a separate form that the feet will be carved from that will then act as a footed ring. The possibilities are almost endless. I call this type of experimentation 'progressive design exploration', since you take an existing profile and progressively explore the different design variables.

Step-by-step

1 The finished tri-footed carob burr hollow form with cubic zirconia inlaid Madagascar rosewood - 10 1/4in high x 4 1/2in wide �

2 Take a carob burr blank measuring 125 x 125 x 305mm (5 x 5 x 12in). Although the blank may appear to have no visible checking, look for bark inclusions on each end. Since the form will taper on one end towards the bottom, the defects can be turned away. Since this is a high-figured burr, the corners are cut off with a bandsaw. The saved corners can be used later to turn small projects like pens and finials

3 To round over the blank, use a 15mm (5/8in) bowl gouge, ground with a swept-back Irish grind (front bevel angle is 45 degrees). To round over the corners, position the flute at 45 degrees and make gentle scooping cuts towards the headstock as you work your way down the blank. Once the blank is rounded over, use a skew chisel to prepare a dovetail spigot on the bottom of the blank for mounting in your scroll chuck. Make sure the dovetail spigot shoulder is at 90 degrees to reduce vibration when mounted in your chuck

4 Press firmly against the end of the blank to seat the dovetail in the chuck jaws. To obtain the best hold possible, turn the spigot to a diameter that minimises any gap between the individual jaw segments

5 To make hollowing easier, drill out the centre of the blank with a large drill to a depth that is 95% of the desired finished interior depth. Reduce your lathe revs when drilling and frequently clear the shavings to prevent the bit from seizing in the hole

6 To shape the profile, use a 15mm (5/8in) deep-fluted bowl gouge with a swept-back Irish grind. The basic profile will be turned using push-cuts with the flute oriented at 45 degrees. Next, shear scrape the surface using the long Irish wings to further refine the surface and perfect the curve

7 You are now ready to hollow the piece. Ensure the lower section of the base is left thick to reduce vibration when hollowing

8 Here, initial hollowing is performed with a captured boring bar, using a 5mm (3/16in) rounded cutting tip. Make cuts from the centre hole towards the outer edge to open up an area large enough for the cutter head. Once you have expanded the hole, primary hollowing begins. Since most of the shavings do not self-eject during turning, you must stop the lathe frequently to clear the shavings. This not only makes it easier to continue hollowing, but it gives you a chance to check your progress visually

9 To ensure an even wall thickness, you can use the Jamieson laser guide accessory or another stabilised hollowing system. I use a business card to set the laser for a wall thickness on this project to 5mm (3/16in). Power sand the exterior from 240 grit through to 600 using a pneumatic 10mm (3/8in) drill with a 50mm (2in) hook-and-loop-faced foam sanding mandrel

10 Here, I used the Sanding Solution passive sanding head (available from The Sanding Glove) to sand the interior of the hollow form. This head mount can be mounted into standard boring bars and allows effortless sanding inside deep hollow forms with control and precision

11 To complete the exterior sanding, if possible, hand sand with the lathe turned off using a Sanding Glove (available from The Sanding Glove, as before), which features Velcro-faced fingers for use with hook-and-loop abrasives. After sanding, the waste wood in the lower portion of the blank is now ready to be turned away

12 Continue using the 15mm (5/8in) bowl gouge to remove the bulk of the waste wood near the bottom of the form, leaving a small tenon on the bottom

13 If you have one, use a Japanese pull saw to saw off the tenon. This is my favourite tool to use when sawing off the tenon to free the form for reverse chucking

14 To reverse turn the form, use a homemade cone chuck turned from Corian and mount on a machined steel bar which is adjustable for different-sized forms. The bar is held in an ordinary Jacob's chuck during turning

15 Once your form is reverse mounted, turn the waste wood on the bottom away, leaving a small tenon. Use a handsaw to cut the tenon in half, being careful to support the form. The bottom nub can be removed by hand sanding, or if possible, use a small high-speed rotary tool, such as a Proxxon with a 25mm (1in) sanding disc to smooth and blend the bottom

16 To explore different leg curves, use a flexible plastic French curve. This allows easy experimentation with different shapes to find a pleasing curve. Once the curve of the feet is determined, trace this onto the face of your leg blanks. Apply a small amount of epoxy into the waste area on all three leg blanks before cutting

17 The three legs are rough cut, but still need final shaping. The ends will be tapered from the top of the leg to the bottom. Much of the thickness shown will be removed as the legs are shaped. To remove the marks from the bandsaw, use an oscillating spindle sander. This makes quick work of the initial contouring. The legs are still glued together at this point (in a small waste area). This guarantees that all three legs will be identical when shaping is complete

18 The top of each leg needs to be relieved to match the curve on the outside of the form. Use a small profile gauge to transfer the curve onto the top of each leg. If possible, use a Foredom tool with a tapered carbide bit to shape the back of each leg where it will meet with the body of the hollow form. To finish, use a spray lacquer that dries quickly and is easy to buff when cured. Apply five coats of lacquer 30 minutes apart and allow the piece to dry fully before buffing

19 Here is my homemade reverse chucking cone centre. The end of the metal rod is drilled and tapped to accept sanding mandrels. This jig can also be used to sand the very bottom centre of projects easily

20 Mount the piece in the jig and prepare for drilling the leg pin holes. A large aluminium cone is also attached to the front of the revolving centre to prevent damage to the bottom of the form. Using the lathe indexing plate, mark, using tape, the three leg locations on the surface. A Kel McNaughton Ornamental jig is mounted in the banjo and will be used to guide the placement of the drill holes

21 Use the large Foredom hand piece to drill the 1.5mm (1/16in) pin holes for the legs. Apply acetone with a cotton bud to a small area around each drilled hole to remove the finish for a better adhesive bond

22 Place a small wooden jig on top of a pin rest located directly on the centre line, to test fit each leg against the side of the form before drilling. Then, drill 1.6mm holes into the side of the form followed by pin holes into the back side of each leg using a standard drill press X-Y vice. Once installed, the pins are invisible, since no drilled hole will show through on the front of the leg

23 To ensure that each leg is positioned correctly on the side of the form, the first leg's curve is traced onto a wooden jig. Apply a small amount of epoxy to each pin before installation. Once installed, each leg's curve is aligned with the original tracing as the epoxy cures. The three legs are now installed and the epoxy has been allowed to fully cure before removing from the mounting. Attach all three legs with blind fasteners - you could choose to stop at this point if you want a blind fixing

24 To enhance the look of the legs, inlay two 2.5mm cubic zirconia presets into the top of each leg - if desired, or use studs. These presets require a 2.6mm diameter drilled hole that is 1.85mm (1 7/8in) in depth. I use precision electronics drills made from solid carbide to ensure the best possible fitting of the preset into the drilled hole. To secure the presets, use a gap-filling cyanoacrylate adhesive. Fit the bottle with a tiny extension tube as this will make it easier to apply a single tiny drop into each hole

25 To install the presets, use a pair of fine point tweezers. Once both presets are installed, wait 5-10 minutes before rotating the index wheel to the next leg to ensure the glue has set


Woodworkers Institute

Tagged In:

hollow form , Steve Russell , Contrasting , Vase , Three Legged

Glossary Rollover a term to view its definition

Bowl Gouge , Scraper , Skew Chisel

"For a new challenge, try adding separate raised legs to your favourite designs"

Materials Used

- A light-coloured carob burr blank (Ceratonia siliqua) for the body of the vase form
- Three feet made from a dark block of Madagascar rosewood (Dalbergia Madagascariensis)
- Two 1.6mm x 5mm chrome- plated steel pins (to attach feet to the body)
- Six 2.5mm cubic zirconia presets in solid 18ct white gold mounting (for accenting)
- Presets require mounting hole 2.6mm diameter x 1.85mm deep

Further Information

Signity presets are available in over 23 countries, please visit www.enlightened.swarovski.com

Diagrams Click an image to enlarge