Simple present I made for my little friend Bogdan, who loves boats, for his 6th birthday. Works on batteries and can be used as a night light.
Step 1: Acrylic Glass Handling
I had some spare pieces of acrylic glass. I put them to fine use in this project. You can easily cut acrylic with a handsaw, as I did here. I cut all of the pieces for the boat and continued to make the drawing on the acrylic. It is easily engraved with a hand held engraver. Prior to make permanent marks you should plan the drawing. You can even draw it on a paper and put behind the acrylic glass you are engraving.
When you have engraved your drawing, glue the pieces together. I used silicone, put a lot an firmly pressed the pieces. If you have some silicone sticking out it is easily cut off after the drying. The silicone can take 24h to dry nicely, so plan to continue the work on your project the next day.
Step 2: Mounting the Stand and LEDs
The stand is made from pieces of wood. You need to sand the wood and round the corners. For mounting the acrylic part make holes and use screws for mounting the glass to the wood. Leave the final piece of wood for later mounting as you will need to put your LEDs before that. You can paint the wood before the assembling but if you like the natural wood color you can leave it as it is. I used some white color spray (that is why my hands are covered with paint).
Put the LEDs to spread light through the glass. You can use hot glue extensively as this side will be covered with another piece of wood. You must draw the anode from each LED as this must be soldered to resistors of 220 Ohm each. You can connect the catodes together and draw this common cathode. In the end you can close and complete the stand.
Step 3: Circuitry
The circuit is very simple. The resistors are hot glued to the back of the stand, as the battery holder and an on/off switch. The LEDs are connected through a 220 Ohm resistor to a source of 3*1.5V = 4.5V which for a LED that has a voltage drop of around 3V gives 1.5V/220Ohm = 7mA. In this design we have 8 diodes which gives all together around 60mA of current. This makes a standard batteries of 1000mAh work 17h. However it is only in theory, because as the battery is emptying the voltage drops and the current drops - the lifetime can be double or even triple.
This can be a good gift for kids as it can trigger child's imagination as it goes to sleep watching the boat float on streams of blue light.