Friday, August 21, 2009

The Harry Potter Style Wand Project

View Video Instructions via this link:
http://www.youtube.com/watch?v=KKiKYfGPeGk
Parts List:
Plastic M&Ms mini candy container tube
3/8" X 12" wood dowel rod
18 gauge speaker wire
Radio Shack switch [part number 275-1571] http://www.radioshack.com/product/index.jsp?productId=2062546
Ultra bright LED
(2) 1.5 volt LR44 button type batteries (or equivalent)
hot glue
heat shrink tubing
paint
gold leafing

Step 1: Drill a small, centered, hole (large enough for the metal leads of the LED to fit through) at one end of the dowel rod. Drill another small hole at an angle from the side of the dowel rod that meets up with the first drilled hole. This allows the LED to fit into the end of the dowel rod and the leads to slide out the side of the dowel rod. These leads are then connected to the speaker wire. [Important Note: make sure the two LED leads are insulated from one another so they don't short across - use some small heat shrink tubing]

Step 2: Cut the speaker wire so that it wraps in a spiral around the length of dowel rod and add some extra length so that it will fit into the M&Ms candy container. The M&Ms container is going to be the handle of the wand that contains the switch and the batteries so allow enough wire for the switch and battery hook up.

Step 3: Solder the end leads (long lead is the positive, short lead is the negative) of the LED coming out from the side of the dowel to the speaker wire. Insulate any exposed area of the wire/leads with heat shrink and test with the batteries to insure a good connection. [Important Note: only use (2) 1.5 Volt batteries for a total voltage of 3 Volts. If the voltage is too great, the LED will fry - unless a resistor is used] LED Note: Current only flows in one direction, so if it doesn't light, reverse the wires to the battery - for more information about LEDs: http://www.kpsec.freeuk.com/components/led.htm

Step 4: Prepare the handle (the candy container) for the switch, batteries, and dowel rod. Turn the M&Ms candy container upside down (don't drill the hole through the end with the lid), and carefully drill a centered hole (roughly larger than 3/8") large enough for the dowel rod and the speaker wire to fit through. With the M&Ms container still facing upside down, drill another hole roughly 5/8" down on the side, with a diameter (approximately 13/64") large enough for the switch to fit through.

Step 5: This step adds the normally open, push button switch (Radio Shack part #275-1571) into the circuit. Test once again to make sure the LED still lights before the switch is wired into the circuit. Don't solder yet, test wire the switch between the positive battery end and the speaker wire connected to the anode (positive lead- long end) of the LED. Connect the speaker wire connected the cathode (negative lead) LED to the negative battery end. Test the switch in the circuit to make sure the LED lights up when it's pressed and off when it's not. Adjust the length of wire needed to fit into the candy container handle and trim the wire as necessary (allow a little extra - because it needs some slack as it gets pushed up into the handle) test again before soldering and test again after soldering. Battery Note: I just taped the 2 button batteries together with some electrical tape to make a battery pack and slid them into a plastic ball point pen cap that I cut down to size and attached the wires through it to either side of the battery pack.

Step 6: Now comes the tricky part, the installation of the switch and the dowel rod with the speaker wire into the handle. Take the nut off of the top of the switch. Open the lid of the candy container and feed the switch up inside the handle tube until it reaches the pre-drilled hole (from Step 4). When it's fitted through (it's tough, but you can do it), reattach the nut to secure the switch in the handle. Feed the rest of the wire and battery pack so that it is tucked away in the handle, and close the lid. Take the dowel rod with the speaker wire and feed it through the other hole drilled in the end of the handle in Step 4. Secure the dowel rod to the handle with hot glue. Check to make sure everything is still working and then proceed to the final step.

Step 7: Chose the color of paint for the wand. Paint it and when the paint is dry, use the gold leafing to highlight the speaker wire that spirals around the dowel.

Wednesday, August 19, 2009

The OWI Robotic Arm Project


I purchased the OWI Robotic Arm Trainer Kit on Sunday, August 9th, 2009.
http://www.owirobots.com/cart/index.php

The Wrist Assembly was finished on Monday, August 10th.

Tuesday, August 11th, both the Fore Arm and the Upper Arm Assemblies were completed.

On Wednesday, August 12th, the project was finished by completing the Arm Base, Battery Box, and the Control Box Assemblies.