Internet version [Naruhodo no Mori] Vol.28

by Yumiko Mori

Vol. 28 April 15th, 1997

Let's use screw drivers

Home science experiments for mothers of elementary school children

Mom: "Kojiro bit again!"
Kojiro is our 4 month old puppy. He is very playful. He bites all sorts of things.
Tae: "What did he bite? "
Mom: "He didn't bite me. He bit an electric cable."
Tae: "Oh, no! It's completely chewed."
Mom: "It's too bad. I've just bought this recently. I have to repair this."
Mom managed to repair the cable using a pair of pliers and a plastic tape.
Mom: "When I was a little girl, my mom often repaired electric cables. In recent years cables are difficult to repair."
Dad: "That's true. Today they manufacture a cable and a socket as a unit, so it's almost impossible to separate them. Perhaps many people never bother repairing broken cables but buy new cables."
Mom: "We have many broken items which I did not throw away; such as a TV remote control, a timer. and a alarm clock. Maybe we can let our children take apart these old machines. This could be fun!"

Toshi, Tae and Satoshi choose what they want to take apart. Toshi chooses a timer. Tae picks a clock. Satoshi chooses a toy and Mom decided to take apart a remote control.
They have started to take apart using screw drivers.
Satoshi: "Mom, can you help me? I can't do it."
Mom: "Screws are very tight. You need force."

Tae: "Which way shall I turn this screw?"
Toshi: "You don't know which direction?"
Tae: "I've found it. It's opposite to clock rotation."

Toshi: "There are more screws inside the box. Oh, I see one screw is loose."
Mom: "You'd better not to touch screws inside."
Toshi: "This is interesting! Now I can see what are inside this timer."

Tae: "Are we putting screws back to where they were?"
Mom: "Yes, you can try."
Tae: "This is a bit tricky. But I finished, Mom!"
Mom: "What's this, Tae?"
There are still parts left on the desk.
Tae: "Oh, no! I have to start over!"

Caution!
I believe the reason why sockets and cord are manufactured as a unit is to prevent short circuit and increase safety.

Materials

Screw drivers (You may need drivers of various sizes and different types (Regular, Philips).)
Broken appliances or toys that have screws

Play with screw drivers

Required time: 30~60 min (depends on what you take apart)

[Planning] Keep broken electric appliances or toys (those with screws) for this experiment.

I don't recommend you take apart still functioning items. You may not be able to put back to where all the parts were.
Toys tend to have small screws. You need small screw drivers.
Never try to take apart big electric appliances such as TV. Possibly very dangerous!

Undo screws with a screw driver. Place screws and the other parts in order, so that it will be easier to put back them properly.

Make sure that the power plug is off.

Rusty screws are difficult to undo. Push screws hard and then turn the screw driver.
If a screw is glued to plastic surface, stick a regular screw driver ((-) shaped head) into the gap and separate the screw from the plastic surface.

An adult should supervise children during the work.

Inspect inside of machines you take apart. Think what role each part plays in the machine.

You may find some useful books, which illustrate mechanisms of various machines.

Put back all the separated parts to their original positions.

Taking apart into pieces can be exciting

I remember that in my childhood I saw my father's hand-made radio. My mother often repaired electric sockets and cords by herself. But now as a parent I've never shown my children how to use screw drivers. No wonder my children don't know how to use screw drivers. When we did this experiment, they were so excited to use screw drivers for the first time. You will not get so nervous if they take apart broken machines. Children may even try to put machines together from parts. Maybe I should try to enjoy repairing as my children did.

Author	Yumiko Mori (Zushi, Kanagawa, Japan)
Illustration	Mitsue Ogata
Translator	Akira Ishihara
HTML format	Muneo Kume