Intro: Flickering Lantern
I love the look and feel of lanterns outside, but lighting and extinguishing multiple lanterns on a nightly basis is just not practical. So what does any engineer with too much time on his hands do... make it electric. The goal of this project was to light up the back yard using multiple lanterns that can be individually controlled for different lighting effects. While I am still working on making more lanterns, the looks of just one working lantern is spectacular. It provides the backyard with a lovely ambiance every night that turns on / off with its built in timer.
Parts list (for one lantern):
1x Hurricane lantern
1x CAN_D box (LED controller)
10 ft outdoor Cat5e black cable (For wiring from the lantern to the box)
1x 10 watt RGB LED (http://ledhacker.blogspot.com/2011/12/led-candle-light-flicker-with-arduino.html)
1x heat sink (http://ledhacker.blogspot.com/2011/12/led-candle-light-flicker-with-arduino.html)
2x sheet metal screws #2x1/4" (for mounting the LED to the heat sink)
dab of thermal paste (for in between the heat sink and the LED)
1x 2 watt 12 ohm resistor (current limiting resistors)(for blue LED)
1x 2 watt 15 ohm resistor (green LED)
1x 2 watt 20 ohm resistor (red LED)
12" of 1/4" dual wall heat shrink (dual wall has the glue inside to help with the water proofing)
1x stick of hot glue (further water proofing)
6" 14 gauge baling wire (mounting the LED to the lantern)
1x Black spray paint (adds burnt / charred look to the lantern glass)
1x Frosting spray paint (makes the glass opaque to hide the LED)
Parts list (for the backyard)
100' outdoor low voltage lighting wire
100' outdoor Cat5e black cable (for networking the boxes)
1x 70w 12v outdoor power supply (can do 7 lanterns at full power, flickering effect requires about 1/3 of the full power) http://www.amazon.com/Intocircuit-Compatible-Water...
Step 1: Frost the Glass
Remove the glass from the lantern
Wash with soap and water
LIGHTLY spray the black paint from the bottom towards the top to add the charred effect. If too much paint is applied, just use paint thinner to clean it and start again until the desired char level is reached.
Let the black paint dry
LIGHTLY spray the frosting paint to keep it from running. Spray from all directions, and in multiple layers, until you can't see through the glass. Don't worry about getting paint on the outside, paint thinner will clean that right up.
Step 2: Install Wiring
Drill a hole near the top for the wiring to come down (good thing these lamps are hollow).
Drill a second hole in the bottom. This hole needs to go through the base AND through the oil reservoir. The hole in the bottom can be much bigger for easier access to the wiring. The hole through the oil reservoir needs to be right where the support meets the base.
Now for the fun bit, fishing the wire through the lantern. I went from the handle down the support, into the fuel tank (needle nose pliers, wd40, and small screwdrivers were all needed). Once the wire is in the tank it is easy to bring it up through the wick hole.
Push 6~8" of slack sticking out of the lantern to wire the LED to.
Step 3: Wire the LED
Mark and drill the heat sink with a 1/16" drill bit for mounting the LED. Also drill a 1/16" hole through all the fins. This hole will be used later for mounting the LED to the lantern.
Put a dab of thermal paste on the heat sink and use the sheet metal screws (#2x1/4") to mount the LED to the heat sink.
Solder the 3 2W current limiting resistors on the LED (20ohm to red, 15ohm to green, and 12 ohm to blue)
Place enough 1/4" heat shrink on the wires to cover the resistors. Solder the orange pair to the red led resistor, green to green, blue to blue, and solder the brown pair to the positive side of the LED.
Test each color of the LED (I have gotten multiple bad LEDs from ebay) before final assembly. Use any 12V power source and just connect 12v to the brown wire and then ground each of the other wires to test the color.
Step 4: Finish the Lantern
Disassemble the wick holder. I have done a couple of lanterns and every one was a little different. Basically you.want the outer most part of the wick holder and the adjustment rod. Everything else needs to be removed.
The outer shell needs to be opened up to expose more of the LED. (Nibblers work great for this)
Drill 3 holds in the outer shell. Two 1/16" holes for mounting the LED, and a larger hole to mount the rod.
Use 14 gauge baling wire threaded through the outer shell and the heat sink to mount the LED.
Finally use some hot glue to help waterproof the top of the LED.
Step 5: CAN_D Box Code
The code is far more complex then it needs to be for just flickering the lantern. One of the reasons I wanted to network them is so I could do more than just create a candle effect. As of right now just the USB input, timer, and flickering work. Fading and CAN network commands still need to be written and debugged.
The flicker effect I used was based off of this much simpler project (http://ledhacker.blogspot.com/2011/12/led-candle-light-flicker-with-arduino.html), but modified to use a RGB LED instead of an orange LED. The red to green ratio is varied by the brightness (brighter = more green and therefore more yellow). The brightness then goes between a random high value and a random low value, pausing at each point of a few mS.
I am currently working on making a CAN_D WiFi adapter that will allow me to control and reprogram the CAN_D boxes over the internet. Hopefully I will have that project working in the next couple of months.IN
Step 6: Installing the Lantern and the CAN_D Box
I had previously made a hammock stand out of railroad ties with the intent of hanging these lanterns from them, so the hook and wiring holes were all ready to go.
Run the wire from the lantern to the box, trying to hide the wire as much as possible. On the backside of the post I use leather strapping with carpet nails to add a rustic look as camouflage for the wiring.
The wiring at the box is simple: 12v, ground, and the CAN high / low wires go in the right. And power, red, green, blue go out the left connector.
Step 7: Finished
Although this project is far more complicated then just shoving some LEDs in a lantern, event just the current outcome was worth the effort.
I am still working on:
Fine tuning the flame effect settings (want a little more color change with the change of brightness)
Other lantern effects like fading between colors
Making more lanterns
CAN network communications between lanterns
Internet control / programming
Step 8: About CAN_D
CAN_D is a project I started summer of 2014 to develop a simple / universal box that can be used in most electronics projects. The idea is to replace the current hobbyist method of a dev board (Arduino, Raspberry PI, etc) and breadboard combo, with a single enclosed box. This project is just one example of the many things that can be done with the box. Currently I am hand assembling the boxes so the PCB / components are not all present or soldered quite straight.
Please continue to follow my instructables for more CAN_D uses, and please visit my website for more info on CAN_D (www.can-dbox.com).