Before I start, I must tell you that this is my first ever instructable and I am 15 years old so I would really like to hear some feedback and constructive criticism from you guys. ALSO, PLEASE COULD YOU VOTE FOR ME IN THE BATTERY POWERED CONTEST AND THE POCKET SIZED ELECTRONICS CONTEST. BIG THANK YOU!
In this instructable, I am going to show you how to make a simple yet effective miniature engraver and drill out of some common items you have probably lying around in your house. --- Yes! This means it can be virtually FREE!
Due to the restriction of the amount of power on the tiny motor that is used, the engraver works better than the drill. To overcome this problem you could use a larger motor with a higher voltage but you would probably have to choose a thicker drill bit as it will have a thicker shaft.
Because this product is so small, it can be taken with you virtually anywhere and be put to use.

MATERIALS:
> Small motor with a relatively low voltage. Also the shaft should have the same diameter as the drill bit and inside of wire casing.
> 2 pieces of wire that are approximately 30cm long.
> Small switch.
> 9V battery clip.
> Wire casing - the same diameter inside as drill bit and motor shaft so they fit snuggly.
> Drill bit - the same diameter as motor shaft and inside of wire casing.
> Pen lid - Preferably on from a BIC pen as thay have only one hole at front.
> 3 1.5V AA Batteries
> Triple AA battery holder with 9V battery clip
> Solder wire
OPTIONAL:
> String
> Tape
> Piece of pen grip
> Piece of plug pin protector

TOOLS:
> Soldering iron - Be carefull as it can burn you and dony inhale the smoke, do it in a well ventilated area.
> Knife

Below is the finished product

Step 1: Soldering the Circuit

Whilst soldering I tried not to make any "Cold" joints and tried to make sure that they were strong however, i feel rather let down on my soldering quality on the switch. Therefore I recomend that you use a clamp to secure the switch and wire as this will make it easier.

Step 2: Attaching the Drill Bit

Whilst attaching these parts, you want to make sure that the wire casing is stiff and not bent otherwise it will cause the drill bit to spin un-evenly. Also, make sure it is a REALLY TIGHT FIT BETWEEN THE SHAFT CASING AND DRILL BIT otherwise it can fly off and CAUSE INJURY.

Step 3: Putting It All Together, Making It Look Pretty and a Result

First I got the pen lid and cut off the clip as it was unnecessary and would be in the way when using the device.
Then I took the whole motor assembly and inserted it into the cap. I then used a dowel to push the motor in to tighten and secure it in place. Hot glue can also be used.
After that I cut a piece off a plug pin protector, put a slit down one side and then put it over the switch contacts to protect then and make it all look neater.
Also, as there were loose wires which are prone to breaking, I took a long piece of string to neaten it all up and support the wires.
To hold the string in place I taped it to the 9V battery clip. On the other side I tied a knot and then stretched a part on a pen grip over the lid, then I tucked the string underneath it.