Step 1: The Materials
an old printer motor,
a piece of PVP pipe with an inner diameter similar to your motors diameter,
an old bit extension,
2x two position 3 pole slide switch (or a single six pole two position slide switch),
an always off pushbutton,
some plastic piece to cover the top of the pipe,
and a gear that has about the same diameter as the bit extension.
Step 2: The Wiring
First: the inverter. It inverts the poles from the power source to reverse the motor.
First glue the slideswitches with hot glue.
Then solder the wires to the plug and then to the middle pole of the slide switches.
Now solder a small piece of wire to one corner of each slide switch.
Solder each small wire to the opposite corner together with another wire (for the motor)
Now solder a pushbutton to one of the wires to the motor and then both wires to it.
Now you're done. Easy, right?
Step 3: The PVC Tube
Mine already had the modifications becouse as I said it was built 2 years ago, but I disassembled it to show you how to make it.
First cut it to leght. It is the lenght of the motor plus 2 or 3 centimeters (more, if you prefer, like for example to put batteries in it).
Now cut a groove to insert your pushbutton wires.
At last drill two holes in it. One for the motor's ventilation (make sure it's aligned with the motor's ventilation hole) and the other to put your pushbutton inside (just to make the pushbutton more leveled with the pipe). Make sure it sits confortably in your hand and that it doesn't cover the ventilation holes, ideally they would be aligned across the diameter).
Step 4: Assembling
1- insulate the electronics with hot glue,
2- insert the motor in the pipe (make sure the motor's ventilation holes are aligned with the ones in the pipe),
3- hot glue the motor in place,
4- pass the pushbutton wires by the groove,
5- hot glue the pushbutton and it's wires in place,
6-hot glue the plug and the inverter in place
7 cover the hole with some package plastic hot glued in place
Step 5: The Chuck
First cut the hexagonal part from the bit extension and keep it (it may be usefel for attachments)
Then drill the remaining hexagonal part (you will know when you have drilled it all becouse they were pressed together and a gap (big) was left after it.
Now with the gear in the motor (dremel from now on) working and a chisel, flathead screwdriver, use it as a lathe and chand«ge the gear's diameter until it is slightly bigger than the space you have created in the bit extension.
Next remove the gear from the dremel and after pouring some super glue in it hammer it into the hole in the bit extension and:
the chuck is made, just put it into the dremel like a regular gear and you now are the owner of an homemade dremel.
Step 6: Attachments
a cutting wheel from a broken bit, a D sized battery terminal and hot glue;
a sanding disk from a lid, a broken bit, hot glue and sanding paper;
a sander from a coffe machine coffee squeezer (I'm sure this is not it's real name, but I don't know it and this is the best description I can give), another broken bit, hot glue and more saanding paper
and finnally bits. They work for any electrocs screw and save a lot of work.
However, I haven't realised yet how can I make a drill bit chuck for this gadget. If anyone knows how, please comment it.