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Bruce Wood – Thin Turning

Demo by Bruce Wood (based on an Eli Avisera design)
Report by: Robin de Haan
Meeting: 19 June 2019

Comprises of three pieces: Cup, Stem and Base. The form is like an elongated stem goblet.

Bruce: “First you make a cup then streeetch it out”

Don’t wear sandals. Do wear a face mask. Stop the lathe before moving the tool rest.

Use fine grained wood with a straight grain for the stem, at least 400mm long, greater than 11mm wide.

Block of wood that will form both the cup and base, about 70mm wide, 150mm long.

Round and Prepare Spindle

  • Centre Punch both sides of the block.
  • Mount block between a drive centre in the headstock and a live centre in the tailstock.
  • At 2000rpm, using a spindle roughing gouge, turn round. Start from ends to centre (to prevent splintering ends).
  • Turn to a (70mm) cylinder. Leave headstock end 70mm wide.
  • Turn a large extruding spigot 60mm or larger on the tailstock side (this will become the bottom of the base). Square off the tailstock side. Dimple centre. Move tailstock away for the next stage.

Start the Bottom of the Base.

  • In the same orientation, move the round to 70mm diameter in self centering jaws (Bruce used 70mm ‘Infinity’ jaws).
  • Using a bowl gouge, turn the 60mm diameter end slightly concave (so the base will sit stably), and make a 25.4mm wide recessed spigot (for expanding pin jaws). Add centre dimple.
  • Finish bottom of base with optional pattern and ‘picture frame’ lines.

Start Hollowing the Cup.

  • Put the 60mm (bottom of base end) into the jaws and clamp them closed. Tool rest across end (perpendicular to bed).
  • At 500rpm, using a 5mm drill bit, go in 50mm (to help hollow and locate the ‘bottom of the cup’ depth).
  • At 2000rpm, using a bowl gouge, hollow the cup.
  • After shaping the cup centre hollow, Bruce used the wing of the gouge with a pull cut (‘back cut’) from centre to edge to finish the cup inner surface.
  • At 2500rpm, using the edge of a negative rake scraper (prefer carbide cutter blade), tidy and finish inside. Move tool rest away.
  • At 500 rpm, sand as prefered (Bruce used 120, 240, 320)
  • Bring tailstock up and drill out the cup centre (for the stem socket). Then move the tailstock to the end of the bed to avoid punctured elbows.

Outside of Cup

  • Move tool rest parallel to bed.
  • At 2000rpm, with spindle roughing gouge, roughly shape the cup upper rim to about 65mm in diameter.
  • Mark the cup inner depth (50mm) on the outside with pencil, and where the cup outer curve will reach bead (about 55mm).
  • Starting at rim, cut downhill, with a ‘cyma recta’ ogee curve, to the diameter of the cup bead (i.e leave more than 15mm at centre which will become the cup bead). Aim for about 5mm wall thickness.
  • Finish with a small spindle roughing gouge, measuring wall thickness with calipers as required. Don’t sand yet.

Outside of Base

  • Keep mounted as is on the lathe, at 2000rpm. Mark 30mm from headstock.
  • With a spindle roughing gouge, starting at the headstock side, shape from the jaws a cove (forming the top of the base). Leave centre at 10mm for the base bead.
  • Use a small spindle roughing gouge to finish shaping the surface. Move tool rest away.
  • At 500rpm, sand the surface if the base (Bruce sanded in reverse from 120, 240, etc).

Sand the Cup

  • Using a thumb inside the cup to brace against sandpaper pressure, sand the cup outer.
  • Supporting the outside of the cup, sand the inside.

Shape the Cup Bottom and Part

  • Mark bead and end of cup bottom.Tool rest parallel to bed.
  • At 2000rpm, use a tiny spindle gouge to carefully shape the bead cove down to 7mm.
  • Use a tiny parting tool to cut the cup from the lathe.

Shape the Base Top

  • Take the big jaw chuck off the lathe. Put small expandable pin jaws in. Expand them into the 24.5mm recessed spigot in the base bottom.
  • At 2000rpm, using a spindle roughing gouge, roughly shape the base.
  • Mark the base proportions – including the base bead – with pencil. (Bruce says “I don’t bother to get the dimensions too accurate).
  • Bring the tailstock up. At 500rpm, with the 5mm drill bit, drill out the base centre to 20mm depth (which will become the bottom socket for the stem). Then move the tailstock away.
  • At 2000rpm, with a mini spindle roughing gouge, shape a gentle cove ‘downhill’ from the tailstock side, to the outer diameter of what will be the bead.
  • Use a small spindle gouge to finish shaping the outside.
  • Then use a tiny spindle gouge to shape the bead. Use calipers to measure the bead cove is down to 6-7mm (carefully don’t cut into the socket.)
  • At 500rpm, sand with grit as required to desired finish. “There’s nothing wrong with using sandpaper for some final shaping”, Bruce says.
  • Decorate as desired. Bruce mentions a ‘texture tool’ will give different results depending on pressure, rpm and angle against surface. Quickly sand over again in reverse with finest sandpaper.

The Stem
“It’s good to have fine, straight grain”

  • Take the wood shaft, 400mm long and 11wide. Measure and mark the lower ornamentation first: The 20mm bottom pin, 5mm bead and 30mm taper, and leave at least 5mm for a bottom spigot. Although these are turned last, you will want to know where the bottom taper begins as you finish rounding the stem.
  • Mount the shaft through the drive centre, preferably using a small pin chuck (or can be mounted in the middle of self centering jaws (or pen turning chuck?)) with most of the length right through the drive centre hole, and only 40mm protruding.
    Stem Cup Pin, Bead and Top Reduction Taper
  • Measure the cup pin hole (Bruce’s was about 24mm long and 5mm wide). Mark depth on shaft.
  • At 2000rpm using spindle roughing gouge turn a pin exactly as wide as the cup hole. Measure pin with calipers periodically (don’t take too much off “You can’t put wood back on”). Test using the cup to see if it fits (spin lathe by hand, while placing cup to pin).
  • Mark bead depth. Turn the top the the stem bead with tiny spindle gouge. Finish with skew chisel.
  • Pull shaft another 30mm out of drive centre. Mark the taper depth.
  • Complete bead bottom and cove with spindle gouge.
  • Use spindle roughing gouge to turn the reduction taper from 10mm bead diameter to 5mm stem shaft diameter.
  • Sand bead and taper to finish.
    Stem Shaft
  • Install ‘French steady’ into tail stock. (Detailed guidance better obtained elsewhere!) Put the French steady waxed string into the cove between stem bead and taper. The waxed string should be looped around the French steady mounting pins to provide support in all directions while not impeding spin. Bruce “Not too tight or the string will melt.” Question “Why not use a 5mm bearing in the tail stock?” Answer “That’s not how it’s done”.
  • Pull the shaft another 50mm from drive centre. Turn to 5.1mm diameter. Bruce used digital calipers to check 5mm diameter while the lathe was spinning.
  • Skew to finish to 5mm using hand support on the other side to counter chisel force. Measure often with calipers.
  • Bring another 50mm of shaft out of the drive centre. Gentle use Spindle roughing gouge and then skew to round. Bruce: “Work down 1mm at a time.”
  • Sand the previous 100mm. Remember to use hand support.
  • Pull more of the shaft out to where the start of the bottom taper is marked (see step 39), about 40mm.
  • Spindle roughing gouge to 5.1mm then skew, with hand support. Sand with hand support.

Stem Bottom taper, Bead and Base Pin

  • Pull shaft another 40mm out of drive centre for the stem taper and base bead. (The stem may flex quite a bit across the 250mm mid length.)
  • Spindle roughing gouge to turn taper from 5mm to 10mm, and round 5mm more for bead. Skew to finish.
  • Spindle gouge to turn cove and bead. Sanding.
  • Use a spindle roughing gouge to shape the base pin down to 5.1mm, and a skew to finish. Check with calipers. Test against the goblet base. Last sanding.
  • Part with a parting tool.
  • Put together
  • Now do it again with a 3mm stem!

Cam Cosford – Goblet

Club Meeting: 5 June 2019
Report by: Murray Wilton

Cam’s subject was actually a segmentation goblet with angled lamination, but the process of planning and preparing the materials and tools was well illustrated. Starting with the story of his first introduction to SAWG and woodturning eight years ago, Cam brandished a massive 25 mm bowl gouge he had been persuaded to buy at Carbatec and suggested he might turn a delicate goblet with it. A little like using a chain saw to cut match sticks.

Cam emphasised that goblet-turning is fine work requiring scrupulous accuracy, and that he personally works to tolerances in the 0.00237 range. (How do you measure that?) The point is that for this kind of segmented work even the starting block has to be dead accurate so that the diagonal end measurements are precisely the same. A little outside the tolerance and the resulting patterns will not align correctly.

Contrasting timbers are needed in order to get the best outcome with the final goblet pattern. Cam was using maple inserts in a block of dark wood (not sure what it was).

As with all projects it is important, Cam teaches us, to start with a plan drawn to scale. The first task is to cut four slots in the bowl end of the goblet block using a drop saw. To prevent the cut intruding into the stem of the goblet Cam has devised a jig which keeps the block sufficiently far from the saw backstop to prevent this happening. All meticulously measured of course. The wedge shaped cuts are to take the maple lamination inserts.

CC Hint No. 1 To prevent the saw blade gripping the timber at the end of the cut and damaging it, always turn the saw off before lifting the blade from the work.

The 10 mm maple inserts are then glued into the cuts and allowed to dry before turning begins. They must be tight as or, in Cam’s inimitable words, “they will wobble round like a how’s your father in a shirt sleeve”!

With the bowl end of the goblet already turned and mainly finished with the Beale system, Cam demonstrated how to finish the stem of the goblet. He uses a jam chuck in the goblet bowl end at the tailstock, and mounts the base end of the stem in a chuck. He set the lathe speed at 800-1000 mm (and couldn’t understand why the lathe wouldn’t start until he realised that Terry S had mischievously turned the switch off while his back was turned). During the demo he occasionally leaned on the speed control dial and inadvertently changed the speed, causing more mirth among the spectators. Using a 55 degree bowl gouge (10 mm, not the 25 mm giant tool!) Cam started working carefully on the stem.

CC Hint No. 2 When working on north-to-south grain timber always work from each end towards the middle to avoid going against the grain.

As the stem became slimmer, Cam’s work became increasingly careful, taking off small bites of timber (more like dust than shavings) to avoid a disastrous jam and a ruined masterpiece. Eventually he got it down to his planned 5 mm diameter and finished with sandpaper.

The final task is to part off the goblet at the chuck end and finish with whatever polishing is called for. If the goblet is to be used for actual wine, finish the inner bowl with polyurethane or lacquer.

For an 8-year veteran, Cam works like pro with four times that much experience. In between the usual banter and good humour, the audience were attentive and went away knowing they had been present at another SAWG class. Many thanks Cam, and we hope you will soon put on the promised class in segmented turning!

Bob Yandell – Cake Stand

Club meeting 29 May 2019
Report by Earl Culham

Bob showed members two examples of the cake stand he intended to make; a single platter on a pedestal, and a two tier platter with a central supporting column. The demonstration would be how to make the two tier version.

Bob commenced by emphasising the need to attend to the basics i.e. plan your project. A little planning will make the project run smoothly. He suggested that the platters could be made from recycled cupboard doors or old cabinet sides. The central column was to be held together by a threaded rod so that the cake stand could be disassembled for storage.

When planning platter sizes, remember that a standard cake size is 250mm but can range from 200-360mm.

The central column included the base, a central spacer and the top which could be turned to your preferred shape e.g. as a handle.

Bob had prepared his support column by drilling a hole through his base, centre spacer and top for the threaded rod. A recess was drilled in the bottom of the base to take the jaws of a 50mm chuck and later the assembly nut. The platters had been cut to round on the band saw and a centre hole drilled to take a spigot.

Once the base had been shaped, the next task was to turn the first platter to round. Bob fitted the base to the platter using the spigot and using the tail stock, pressed the platter against a large disc mounted on a faceplate. With the lathe running at a slower speed, this was a quick and effective method of holding the work for finishing.

The centre spacer was turned to shape and the same method of using tail stock pressure for holding the second platter would have been used. However there was a technical problem and the project was not completed.

Thanks Bob for a well planned demonstration.

Terry Scott – Pens

So the plan was to have a hands on night, where each member of the club made a slimline pen.

As there have been many new members since the last attempt at something similar, Terry started with a “short” demo. Of course Terry the proceeded to try and get everything he could about how to make a pen into the demo, here is a quick report of the major points.

Blank – 20mm square cut slightly longer than tubes

Mark to keep grain aligned

Drill a 7mm hole for the tube – alternative methods of drill press with jig or on lathe using pin or pen jaws were discussed

With lathe option about 500rpm. Make sure you align the lathe head first.

Rough up the outside of the brass tube with some sandpaper

Put potato plug in end of the tube to prevent glue going in.

Glue into blank with superglue

Mill ends of blank – don’t use vice as may stretch brass tube.

Put the blanks on a pen mandrel with bushes to match pen kit.
Mandrel saver (live centre) presented as an option instead of default knurled nut.

Turn lathe up fast as you are turning a very small diameter.

Cut from the centre out with spindle roughing gouge.

Skew for finishing cuts

Sand through grits -240 320 400

Use U-Beaut EEE-ULTRA SHINE to get a high polish.

Terry the used SHELLAWAX GLOW to finish.

Take the matching pair you have just turned – keeping the grain aligned. Terry suggested if turning a lot of pens to make up a board with 4 inch nails to keep them together.

Assemble pen – taking care to put mechanism in correct distance into the pen to have the point protrude the correct distance and allow it to retract.

Terry then gave a quick demo of the disassembly process if you want to refinish a warn pen or replace some parts.

The crowd then went to the lathes and the real fun began. Many people taking home a successful first pen.

Thanks Terry.