Tapered Staved Vessel archive

Thursday 4 August 2011

Carrying on from the last issue, Dennis Keeling produces a tapered staved vessel from various timbers using the bandsaw sledge previously made

Gallery

Following the recent article on how to make a staved sledge and biscuit barrel, this article takes the format further by creating an advanced tapered staved vessel. This time, you will use the bandsaw sledge to produce tapered staves and I'll show you how to produce a lid from concentric segments; this is the Holy Grail for segmented turners.

Tools used: 20mm (3/4in) bowl gouge, hollowing tool, shear scraper, flat-end scraper, round-nose scraper, fingernail gouge and diamond parting tool

Construction

Step 1

Start by cutting the staves to size using the circular saw and cut into tapered segments using the bandsaw sledge that was featured in the previous article. Set the bandsaw to a mitre angle of 11.25 degrees and the sledge taper to 8.5 degrees. It's worth experimenting with some scrap wood to check the bandsaw angle and sledge taper

Step 2

Now cut the 16 olivewood staves on the bandsaw using the sledge. Hold them in position using the toggle clamp

Step 3

True up the faces on the planer thicknesser with the back-plate mitre angle set to 11.25 degrees. Hold eight staves together with gaffer tape to check the angle

Step 4

Cut the ebony separators oversize on the bandsaw and then bring down to the correct thickness on the drum sander. It is easier to glue the ebony separators to each stave separately and let them dry, before trying to glue up the main composite

Step 5

Glue the main composite up in two halves - without the two centre separators - to allow the halves to be trued up before finally gluing the whole composite together. Use plastic separators to keep the two halves apart and elastic bands to hold the staves together whilst gluing. The more rubber bands you use the better, as this will ensure the joints are held tightly whilst the glue dries

Step 6

Flatten the edges of the two halves on the planer, ready for gluing

Step 7

Glue the two halves together with the added ebony separators. An aliphatic glue with an extended open time enables the staves to be glued together without the glue grabbing too early; you can then adjust to the correct shape with the rubber bands. It's better to leave the composite to dry for at least 24 hours to allow the many glued surfaces to dry out. The glue does significantly increase the moisture content of the wood

Step 8

True the top up and glue onto a 200mm (8in) ring of 17mm (11/16in) MDF mounted to a wooden faceplate; this will be used to hold the composite in the chuck for the base to be constructed. Mount the composite on the lathe using the wooden faceplate with the base centred on the tailstock using an MDF cone

Step 9

The ebony segment rings are constructed from 16 segments cut on the bandsaw at a 11.25 degree mitre angle. Clean the edges up on a disc sander and first glue into two eight-segment semi-circles. When these have dried, remove the excess glue, true the edges up on the disc sander and then glue into a circle. Repeat this process for the top segment ring and the segment rings for the lid. After the rings have dried, clean one surface up on the disc sander ready for gluing to the composite

Step 10

Now glue the ebony ring above the base to the composite. Centre it on the tailstock using a flat MDF disc. After it is dry, glue the base disc of olivewood to the ebony ring and also to a wooden faceplate for mounting on the headstock later

Step 11

Now turn the composite round on the lathe with the base now supported by the lathe chuck and the top, with its MDF backplate, at the tailstock. True up the outside of the MDF backplate to act as a runway for the three-point lathe steady. Cut the inside of the MDF disc away with a parting tool to open up the inside for hollowing out

Step 12

Hollow out the inside using a hollowing tool. Even though the staves are straight, it is more aesthetically pleasing to have a curve at the bottom and the top. Remove the minimum amount from the inside at the top and the bottom, and then remove the maximum from the centre of the composite. After getting the inside to approximate size, clean up the inside with a negative-rake side-scraper

Step 13

You can now glue the ebony ring to the composite - positioned on the tailstock using a back-plate. Now leave the glue to cure for four hours. Support the inside with a cone on the tailstock and bring the outside down to size. Initially use a bowl gouge - from the centre of the composite to the top or bottom - to follow down the grain direction. Clean the outside up with a flat end negative-rake scraper

Step 14

The inside and outside can now be sanded - it's better to sand with the grain direction to ensure there are no rotary sanding marks. Break the paper joint to the faceplate with a sharp knife and reverse chuck the vessel onto an MDF cone faceplate with a small steb-centre in the tailstock. The bottom can now be hollowed and finished

Step 15

You can now construct the lid. This consists of four segment rings that have to be built separately and each mounted on MDF faceplates with a paper glue joint

Step 16

Using a diamond shaped parting tool, face and trim the largest ebony ring to size on its faceplate

Step 17

Trim the large olivewood and ebony segment ring to size, just so it fits inside the outer ebony ring

Step 18

Glue the two together using yellow aliphatic glue. Hold them between centres using the tailstock to position and press the rings together. Remove the wooden back-plate on the tailstock by breaking its paper glue joint with a sharp knife

Step 19

Add the inner ebony ring the same way and trim to size using a scraper

Step 20

Flatten the inner segment ring and trim to size to fit into the ebony ring. Glue the two together as before and remove the back-plate after the glue has dried. Now repeat the process for the other segment rings

Step 21

When the lid composite has been fully assembled and glued, turn the inside flat using a bowl gouge and then a flat negative-rake scraper. Adjust the edge to just fit the staved vessel

Step 22

Drill the centre of the lid to accept the ebony knob, which you will need to turn on the lathe beforehand. Separate the lid from the faceplate paper-glue joint and then clean the top surface up before adding the knob. Sand and finish the vessel down to 400 grit before applying three coats of satin lacquer. Rub the parts down between coats with a fine Webrax pad; this will de-burr the wood ready for the next coat of lacquer


Tegan Foley

Tagged In:

Woodturning , vessel , Dennis Keeling , segmented , tapered , staved

About The Author

Dennis Keeling has been turning for nearly 15 years, first as an amateur, and now as a professional turner. He is one of the leading exponents of segmented turning in the UK and is on the Register of Professional Turners (RPT). He has produced a DVD on segmented turning, undertakes one-to-one tuition in his well equipped workshop and demonstrates segmented turning both in the UK and USA
Email: dennis@dkeeling.com

Additional Tools

1. Circular saw
2. Planer thicknesser
3. Bandsaw
4. Stave cutting Jig for the bandsaw
5. Drum sander

Time Taken & Cost

Time taken: 8 hours to make (spread over 5 days for gluing and finishing)
Cost: £35

Design

The staved construction design of the vessel uses 16 tapered olivewood staves with 16 3mm (1/8in) ebony separators. The staves are tapered at 17 degrees
Base: The base is solid olive with a 16 segmented ring in ebony. The top is also a 16 segmented ring constructed from ebony
Lid: The lid is made from a solid olivewood centre with four concentric rings of ebony and olivewood made from 16 segments each
Knob: The knob in the centre of the lid is made from solid ebony
Dimensions: The finished vessel stands at 185mm (7 1/4in) high and 175mm (6 3/4in) wide at the top. See plan and cutting list

Handy Hints

1. Make sure the Olivewood is very dry. This timber is prone to warping and cracking as it dries
2. For this particular project, use a glue with an extended open time; this will allow the segments to be assembled without fear of the glue grabbing
3. Use a solid centre core to the lid otherwise the joints will part
4. Beware, olivewood is very tactile; everyone wants to touch it!
5. With complex projects such as this one, it is worth taking your time and getting it right

Diagrams Click an image to enlarge