Lidded Bowl with Finial from Half a Log

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Lidded Bowl with Finial from Half a Log:
Andy Coates looks at a commonly made object and deconstructs it to make something more interesting.

Andy Coates looks at a commonly made object and deconstructs it to make something more interesting

Once in a while you obtain a log of something special. It might be the grain, colour, or species that makes
it ‘special’, but whatever it is that distinguishes it, you are often presented with a conundrum; use it immediately in the excitement of acquisition, or save it?
I have a laburnum (Laburnum anagyroides) trunk that qualifies as a log, and as such it is not something I would be comfortable using recklessly. As much of the wood as possible ought to be used to get maximum use from what is becoming a rare commodity.
There is something I regularly turn that is perfect for a project with such constraints: a lidded bowl from a single blank, where even the finial comes from the same block of wood. I prefer to use a wood with some character, striking or at least obvious, grain and for preference some distinction between heart and sap wood; all these add to the finished object. Due to the method used to produce the lid the grain will align upon finishing and if you can manage to incorporate the sap/heartwood boundary, even better as this adds to the visual dynamic considerably. This is also a useful methodology for expensive exotics as it reduces waste dramatically.
This is also a useful methodology for expensive exotics as it reduces waste dramatically, and negates the necessity for two expensive blanks when producing a lidded bowl. You might also consider it useful for simply making the most of a bowl blank by producing a second blank for a different project; it not only makes financial sense, but also reduces the amount of shaving you have to dispose of at the end of the day.
The coring method I use here is by no means the only method available, but to my knowledge there is no dedicated system for sub-150mm blanks such as is available for larger coring jobs, and whilst not entirely ideal, it is an adequate method which does produce useable secondary blanks. Keep in mind the stresses, on both your body and the blank, take things slowly, withdraw from the cut regularly to remove shavings, and all should go well.

Tools
• 10mm long-ground bowl gouge
• 10mm parting and beading tool
• 2mm parting tool
• 10mm long-ground spindle gouge
• Modified Robert Sorby slicer
• Hot-melt glue gun
Materials
• Half a 150mm log, 190mm long
• Abrasives 180–400 grit
• Cellulose sealer
• Danish oil
• PPE: Facemask, gloves, dust mask/respirator

Drawings and how to resize them
To enlarge or reduce the size of drawings right click on the image to download it and then go HERE to watch a video on how to use paper with a grid to do exactly that.

1. Mark out the disc on the half log. If you have a log with heart and sapwood try to ensure you include the sapwood in the disc. Then mark as many square blocks as you think you can achieve (they’ll always come in handy). Take care cutting them on the bandsaw. You need a disc and two small blocks 25 x 25 x 65mm

2. Mount the disc on a screw chuck held in the four-jaw chuck. Using a long-ground bowl gouge rough the disc down to a cylinder and then clean up the face of the blank. Be wary of removing the sapwood at the headstock side edge of the blank. Aim for a finished disc diameter of approximately 160mm

3. Using a 10mm parting and beading tool, clean up the first 10–25mm of the inner face at the headstock side of the blank. This will provide a reference surface for shaping the bowl. Mark 6mm in from the finished surface to provide a rough marker or finished rim thickness. The actual rim of the bowl will come out around 4mm

4. Begin removing waste from the tailstock-side corner of the blank, working down to produce a tenon for your chuck. If you have a revolving ring centre use it to mark the centre of the blank as a reference for later. Ensure the tenon is accurately sized

5. Begin shaping the bowl, working from the rim mark you made earlier. The shape is a long slow ogee with a sharp return to the base. Set the shape in the upper half and carefully sweep the curve back towards the foot. Leave the last section as waste to support the next stage

6. When you have the shape set, use a sheer scraper to refine the shape and surface. You will return later to complete the last section. Abrade the exterior shape to 600 grit, seal with three coats of cellulose sealer, de-nibbed between each coat

7. Remove the blank and re-mount in the chuck jaws. Clean the face surface up and make flat using a push-cut to centre. Mark and cut a recess 50mm diameter and 5mm deep to suit a set of O’Donnell jaws. Make a pencil mark about 20mm in from the rim

8. Using a ‘slicer’ type tool (I use a modified Sorby slicer), begin to core the middle from the blank. Aim to take a cone from the 20mm mark that will conclude approximately 10mm above the ultimate base of the inner bowl (see diagram). Cut slowly and withdraw to clear shavings regularly

9. As the slicer gets close to centre you will hear a change in the noise, indicating the stub is getting close to parting off. At the this point you can stop coring and apply firm pressure on the edge of the core to snap it out of the bowl. Support the back of the bowl with fingers to resist the pressure

10. Remove the chuck with the bowl still in place and mount a second chuck with medium O’Donnell jaws, or swap jaws if you only have one chuck. Begin to turn a shallow dome on the top and cut a 45mm tenon on the blank. Clean up the edge to a flat surface. Abrade to a finish and seal as before

11. Before you proceed, measure the lid diameter and check its ultimate position in the body of the bowl. It should be around 105mm diameter and leave a bowl rim of approximately 28mm. Reverse the lid in the O’Donnell jaws

12. At the face edge leave a flat 3mm wide, then using a 10mm spindle gouge turn the inside of the lid aiming for a 4–5mm wall thickness. You will cut through the screw chuck hole. Clean up the hole edge leaving a parallel side to it

13. With the tip of the 10mm parting tool cut a V cut at the edge of the flat and scorch it with Formica. Abrade the interior of the lid to 600 grit, apply three coats of cellulose sealer, de-nibbed between coats,
and buff to a high sheen

14. Remove the lid and second chuck (or replace original jaws and carefully remount bowl ensuring it runs concentrically) and replace first chuck holding the bowl on to the lathe. Re-measure the lid diameter and transfer the dimension to the interior of the bowl. You can use a pencil line or a scribed line, but ensure it is accurate

15. Using a small parting and beading tool, cut a slightly dovetailed recess 6mm deep and 3mm wide to accept the lid. The dovetailing provides for incremental adjustment to make a tight fit. At this stage you want a tight fit. With the lathe stopped, keep testing the fit as you go

16. If you are uncertain about completing the lid unsupported you can apply four small spots of hot-melt glue around the rim of the lid, or conversely bring the tailstock up for light support, but this will restrict the turning, and will need to be removed for the last stage

17. Using a 10mm spindle gouge complete the shaping of the top of the lid. Take light cuts with a freshly ground tool, working from the centre towards the rim to avoid ‘popping’ the lid out. Leave a raised boss in the centre and when the screw chuck hole is revealed clean the inside face to match the previous cuts

18. When the lid is completed, abrade and seal as for previous sections. I added another V cut and scorch mark at the edge of the boss. Now use a 10mm spindle gouge to complete the bowl rim, sweeping the convex curve down to the recess edge neatly. Abrade and seal as before

19. Remove the lid from the bowl. Now hollow the interior of the bowl using a 10mm bowl gouge. Be careful to leave the 3mm internal recess. Aim for a smooth, continuous curve that ends in a curve and not a flat. Sheer scrape, abrade, and seal as before. Adjust lid fit with abrasive if required

20. Bring the toolrest around to the back of the bowl. Using the spindle gouge, for ease of access, complete the shaping of the last portion of the bowl. Sweep the ogee in to produce a pleasing flow from the rim.
Keep checking wall thickness as you work

21. Work down to terminate at a raised foot, 50mm diameter. At this point the foot can be deeper than required to provide access. Sheer scrape the surface you have turned, abrade to 600 grit, and seal with three coats of cellulose sealer

22. Remove the bowl from the chuck and mount a soft-faced jam chuck. Remount the bowl using the mark left earlier by the revolving ring centre to centre the bowl on the jam chuck. Turn the tenon away and clean up the surfaces

23. Reduce the depth of the foot to 10mm, and turn a shallow concave surface on the base. Abrade and seal as previously, ensuring the two surfaces are blended flawlessly

24. Mount one of the small square blocks in some pin or engineering jaws. Turn a finial 30mm long and 14mm diameter. Put a 2mm tenon on, to the diameter of the hole left by the screw chuck after you cleaned it up. Abrade and seal as previously, then part off

25. Mount the second small square in the engineering jaws. Turn a small 15mm diameter button with a 2mm tenon to the diameter of the screw chuck hole. Abrade and seal as previously, then part off

26. Using CA glue fix the button and finial in place, ensuring the grain direction is aligned. You will notice that despite being essentially upside down, the grain in the lid will align almost perfectly. This is a pleasing
by-product of coring the lid in this way. Now you can oil the whole thing and sign the base

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