Step 1: Parts Used
1. 5 inches of 0.01" 70 degree Nitinol wire
2. A 5 volt power supply .5 amps (this can be replaced with a usb cable)
3. A small wood box from a craft store
4. Two ring lugs
5. Two 3mm counter sink screws and nuts
6. Two plastic wire ties
7. Some 30 AWG hookup wire
8. Super glue
9. A small piece of balsa wood.
10. A 2K resistor and a TIP31 NPN Transistor
11. A 555 timer kit
Step 2: Assemble the Electronics
Step 3: Make the Nitinol Actuator
2. Wrap the wire around a nail or other metal rod and use a small piece of 30 awg wire to hold the Nitinol wire in place.
3. Heat the Nitinol wire in an open flame. This will reset the memory of the Nitinol and turn it into a spring shape.
4. Remove the Nitinol from the nail and solder a 6" piece of 30 awg wire to each ring lug
Step 4: Prepare the Wood Box
1. Cut a slot in the wire mesh so the screw on slider won't be obstructed.
2. Glue the head of a screw on the underside of the lid. This is were you will attach one end of the actuator.
3. Drill a small hole in the back of the box for big enough for the power cord to fit in.
Step 5: Make the Balsa Wood Slider
2. Glue the head of a screw to the back side of the wood slider. Make sure it lines up with the slot in the mesh inlay of the lid.
When the balsa wood slider is placed in the inlay make sure it slides it back and forth easily with very little resistance.
Step 6: Make the Return Spring
1. Use a straight pin to poke a hole in each end of the wire tie.
2. Put a short piece of 30 awg wire through each end and make a loop big enough to fit over your screws.
Step 7: Assemble Lid Parts
2. Install the actuator on the two screws and bolt them down.
Step 8: Install the Timer Board
2. Feed the power cord through the hole you made in the back of the box and connect it to the timer board.
3. Attach a plastic wire tie to the power cord to prevent it from being pulled out of the box.
Step 9: Adjustments
2. Adjust the pause pot so the slider only moves around every two minutes. I adjusted it faster for the video.
3. Shim the wood slider so it is even with the top of the box.