TURNING A MOULD

Now it is possible to shape the mould with a chisel. Wear a mask over your mouth to avoid inhaling the dust. Beware of loose clothing, which may become caught in the rotating mould.

 

Turning a stator mould on an electric motor

 

Cut a smooth surface on the inner edges of the stack (diagram 1 7).

The surface tapers at about seven degrees.

The overall diameter at the outer edge is 380mm

The diameter of the flat face is 360 mm.

The corner inside is smooth (slight radius) not sharp.

 

THE SHAPE OF THE STATOR MOULD

7

Turn the inner disk down to 1 30 mm diameter on the face (see diagram 1 8), with a taper. The corners are rounded as before.

 

0

SECTION

IT

HOLE

Place a coil against the face of the mould and check that it fits comfortably - if not, then the hollow must be made a little larger, or the centre disk a little smaller. In the end, the coil's centre must be at 250 mm from the mould centre. Remove the mould from the lathe or motor.

19.HOLES IN THE MOULD

Drill four holes in the central part which are used to separate the two moulds (diagram 1 9). Screw some small pieces of plywood onto the underside of the mould to make 'feet'.

Stator Inner mould

• Cut disks with diameter 370mm

20 degrees

20. INNER MOULD

SECTION

20deg

325 368

HOLE

\

45

Sawing flat faces on the inner mould

Drill a 12mm hole at the centre of each

Glue them into a stack (diagram 20), using a 1 2mm bolt to

centre them.

The stack is at least 45 mm thick, better 50 mm.

Turn a 20 degree taper on the rim, and round off the corner,

so that the diameter reduces from 368mm to 325mm.

Check that the outer mod fits over the inner mould, with a 6mm gap all around the edge. Then remove the inner mould from the faceplate.

Draw 2 lines on the larger face of the mould, 340mm apart (diagram 21)

Cut two flat faces, as shown in diagram 21