Miniature Bat Automaton

This is more of a guide than a detailed set of instructions. The photos will be a mix of shots I took during the making of three slightly different versions of the automaton.

This automaton is made from a mix of things from my stash, or rescued from my recycling. Almost everything could be substituted by something else you can find:

• Toilet roll tube
• Stiff steel wire (a big paperclip from my stash)
• Thin steel wire (from my stash)
• Thin fabric (I used a non-woven cleaning cloth)
• Medium thickness card (I used a mail-order envelope)
• PVA glue

The tools I used were the usual crafting suspects: sharp knife, scissors, wire cutters (which all happen to be on my Leatherman), plus a pencil and a black marker.

Cut the toilet roll tube in half, and then cut one half in half again.

Cut one of the quarters along its length to make a single curved strip of card.

Cut half way along the half-tube on both sides.

The short strip should wrap around the longer tube so that the end of the cuts are just visible above the cut strip.

Start by straightening your big paperclip.

The crankshaft is made by making a series of 90 degree bends.

The easiest way to describe how is to show you the series of photos of the bends...

To describe the bends for the automaton in this build, starting from the end away from the handle...

1. Go about 1cm, turn left.
2. Go just over 1cm, turn right.
3. Go just under 1cm, turn right.
4. Go as far as you did in step 2, turn UP
5. Go about 1/2cm, turn forwards
6. Go just under 2cm, turn Down
7. Go as far as you did in step 5, turn left
8. Go as far as you did in step 2, turn right.
9. Go as far as tou did in step 3, turn right
10. Go as far as you did in step 2, turn left
11. Go about 1cm, turn left
12. Go about 2cm, turn right
13. That leaves about 2cm for the handle.

The actual distances of the parts of the crankshaft change the way the final bat will fly, and they are worth experimenting with, but the two outer sections of the crankshaft need to be further from the centre of rotation than the long middle section of the shaft because the ends of the wings move further than the "elbows" of the wings.

You also need to test-fit the shaft in the base - press the crankshaft into the slots you cut, and give it a few turns to make sure it doesn't jam against the inside of the tube.

You will be fastening thin wire to the ends of the cranks. To stop those wires slipping out of place, and to allow them to turn, you need to cut short strips of paper and curl them around the ends of the cranks.

The strips need to be the same width as the end of the crank, and curled snugly around them so that they do not slip out of place. Smear a little glue on the end of the strip as you roll them in place.

Cut four equal lengths of your thinner wire.

Wrap the ends of each wire around the paper strips on the cranks - one on each end, two on the middle section.

The driving wires need to be guided.

Cut a circle of thick card that fits snugly into the end of the toilet roll tube.

Mark a row of four dots that match the distances between the driving wires.

Pierce the dots with a needle or pin.

Slot the crankshaft into the base, with the driving wires poking out of the top of the base.

Thread the driving wires through the holes in the cardboard disc - make sure you get them in the right order!

Press the disc into place.

Glue and wrap the quarter-tube (from step one) around the base, just under where the crank shaft sticks out of the base.

Set the base and mechanism aside to dry while you work on the bat.

For reasons that will become clear, your bat needs four wings and two bodies.

Sketch out a shape that you like, and then cut it out to use as a stencil to get matching wings and bodies.

Cut them out, then cut the wings across the "elbow" (in a real bat, I think this is the wrist).

In the centre of one set of wings, pierce a small hole with a pin or needle.

From your scrap of fabric, cut four rectangles that are large enough to cover the joins between the parts of the wings.

Glue them in place on the wing-pieces with the holes in them. Make sure you leave a gap of a couple of millimetres to allow the wings to bend.

Between the wing and the body, glue the fabric on top of the wing, but then bend it down and glue it to the bottom half of the body.

Set them aside to dry.

Trim your fabric with fine scissors (curved nail-scissors are ideal).

Glue the two halves of the body, and press them together.

If you want, you can bend the ears apart before the glue dries, to add a little character to the bat.

Set aside to properly dry.

When the body is dry, thread the driving wires through the holes in the wings.

Pay attention to where the handle is - if you're wanting to watch the bat fly yourself, arrange the mechanism so that the handle is on the side of your dominant hand, then make sure the bat is facing you when you thread the wings onto the driving wires, and that the fabric hinges are on top of the wings.

Bend the tips of the driving wires over by 90 degrees, then glue the remaining parts of the wings on top to trap the bent wires in place.

Clamp, and set aside to dry.

(Because of the small size of the automaton, I found it easiest to glue the wings a part at a time, tips then shoulders, with paper clips as clamps.)

Bats are not normally the colour of cheap card.

Simply colouring the bat with a black marker solves this, although you may need fineliners to get into nooks and crannies.

You could paint the bat, of course, but I don't know what the paint will do to the flexibility of the hinges.