WOOD MATERIALS TECHNOLOGY

4th Edition

Chapter 25Woodturning

Woodturning lathe

For safety, only your teacher should adjust the speed of the lathe – if in doubt, ask

Drive mechanismPulleys inside the lathe Drive speed

There are 2 types of turning:

Turning between centres:

These use the centres shown above. This is also known as spindle turning.

Face plate turning

Used for turning wide hollowed out objects like bowls etc.

Centres support the work while turning

The drive centre grips the end of the piece and it turns the wood with the speed of the motor.

The hollow centre is used when boring a hole through the middle of the piece.

Centres

Drive centre

Live centre

Hollow centre

Banjo & tool rest The tool rest is adjusted when bowl turning

Tool rest

Chuck and faceplatesChuck Faceplates

Woodturning tools

GougesThere are different gouges

− Roughing out gouge− For roughing down in

the early stages

− Spindle gouges− Smaller and more

precise than rough gouge

− For finer work and concave pieces.

Gouges

Gouges are used to make coves

They are also used when turning bowls and dishes

Skew chisel

Used forBeads and ‘V’grooves

Skew chisel with edge swept back

Parting tool

Used to cut beads and make incisive straight cuts into a piece.

Taking measurementsCallipers are used to

– measure the round sections of turned wood

– transfer measurements from a drawing

Wear full face protectionTie up long hair and secure

loose clothingRemove jewelleryAlways get permissionSecure work on the lathe and

get it checkedRotate the piece by hand

before turning on the latheSwitch off the lathe before

making adjustments

Safety

Join the diagonals to find the centres at each end of the piece

Draw a circle in the square Plane down the corners Small saw kerfs can be cut into the

ends for added grip Insert the drive centre Insert the piece into the lathe at both

centres, lining the centres up carefully

Preparing to turn – spindle turning

Lock the tailstock in positionTurn the handwheel to push the

tailstock centre into the workPosition tool rest as close to the work

as possible, setting in at centre height

Spin the work by hand to make sure it does not catch on the tool rest

ProfilesProfiles show the

outline of a turned piece

Profile templates assist in making copies of the same profile

Boring holes on the latheHollow centre put in tail stock

− The piece is secured with a hollow centre in the tailstock

− Hole bored through the hollow centre half way

− Remove auger often to clear shavings

− Reverse piece and repeat the process

Drilling a holeLong hole boring kit

Boring holes on the lathe

Drilling a hole – alternative

Groove two pieces in the centre using a routerGlue the two pieces together to form the blank

Join the diagonals to find the centre of the piece

Draw a circle in the square Remove the corners using a

saw Locate the faceplate onto

the centre of the blank and secure

Faceplate is screwed onto the spindle of the lathe

Adjust tool rest and check the piece rotates freely

Preparing to turn – Bowl/faceplate turning

Spigot and socket joints are used to join two turned pieces

A hole is drilled into one piece

The spigot is turned on the other piece to match the hole

Outside callipers used to measure this

Joints

TIMBER SUITABLE FOR TURNINGBEECH: Fine texture, pinkish buff

CHESTNUT: High quality work resembling oak

ELM: Light brown in heartwood, yellowish white in softwood. Suitable for bowl turning, not to be used with carbon steel blades

SYCAMORE: Whitish with a close-fleck grain. Used for dairy and kitchen implements such as churns, rolling pins and bowls

TIMBER SUITABLE FOR TURNINGWALNUT: Pale buff to dark brown

SCOTS PINE: Matures to rich honey. Ideal for practice

ASH: Pale grey tinged with pink; heartwood light brown. Coarse texture but turns very well for handles of tools, farm, gardening and sporting equipment

Wood turning speeds

Diameter of piece Turning speeds at RPM(General cutting speeds)

0-50mm 3000 rpm

50-100 mm 1500 rpm

100-150 mm 1000 rpm

Quiz

2007 hl

2011 hl

2008 hl

Name the parts of the lathe

TailstockHeadstock

Name the parts of the lathe

Bed

Tool restDrive centre

On/off buttons

– Wear full face protection– Tie up long hair and secure loose clothing– Remove jewellery– Always get permission– Secure work on the lathe and get it checked– Rotate the piece by hand before turning on

the lathe– Switch off the lathe before making

adjustments

State some safety precautions to be followed when using the lathe

Name two woodturning tools

− Woodturning gouge

− Skew chisel

Beech− An attractive hardwood− Close grained wood− Free from defects− Finishes well

Scots pine– It is easy to work– Finishes well– Has an attractive grain

pattern

Name two woods suitable for turning. Why are they suitable?

With the aid of notes and neat freehand sketches describe a method that could be used to make another leg identical to the one shown.

− Profile templates are used to make identical copies of turned pieces