Intro: Fabulous LED Tree
This is a fun and easy little tree that only takes a few hours to complete. It can take much longer if you really get into it, but the basic thing is pretty quick. The only item that might be a problem for you is the solder pot. It really helps to have one for this project, though you can still make this tree without one. You can pick up a decent solder pot for about $50US on Amazon. Or borrow one.
These trees make great decorations for nearly any holiday or special occasion. They also make great gifts. Oh, and they are really cheap to make. I think the one I made for this 'ible cost less than $5US - and that was mostly for the magnet wire.
Tools you'll need:
- Eye protection (Absolutely necessary)
- Protective gloves (helpful)
- A drill
- Wire cutters
- Soldering iron
- Solder pot and solder.* This is the most efficient way to do this. You can also use a butane torch or even a cigarette lighter to melt the the enamel coating on the magnet wire, then remove the coating with sandpaper. A little tedious, but workable.
- Spring Link (looks like a carabiner) - optional, but works great
Supplies you'll need:
- Magnet wire - 22 gauge - 3 colors green, red, copper. You'll need about 20’ of each color for each tree.
- LEDs - 3mm or 5mm - depending on how subtle you want the lights or what you have around.
- A power source: The voltage required by standard LEDs is 2V - 3.2V, give or take, so you have a bunch of options. Here are a few:
- AA batteries
- AAA batteries (won't last as long as AA)
- USB - modify a USB cable and power the tree from your computer
- USB - modify USB cable and use an old iPad charger or other 5V USB wall wart. This is the method I'm using since I have extra adapters from my job.
- A 5v wall wart from some other electronic device.
Use a multimeter to see what the voltage range is. Some of these are switching supplies and are well regulated at or near 5v, other, non-switching supplies can vary by a lot and aren’t the best choice for this project but can produce interesting effects.
There are several good basic Instructables on this site to help you figure this out. If math makes your head hurt, go with a 100 ohm resistor.
A note about resistors: It’s standard practice to use them, so use them, even if you only need a tiny one. Your tree will light up without one, but the lifespan of your LEDs will be compromised if they are getting more voltage than they can easily handle. They can get hot and bothered and just plain quit on you. Or they could start a fire, if you’re really, really, really unlucky.
* Warning: A solder pot used carelessly is a very dangerous thing, so be sure to set it in a protected area with appropriate supervision if doing this project with kids or over-stimulated adults.
The standard disclaimer applies to this Instructable: Follow these directions at your own risk. The author is not responsible for anything that happens to you or anyone around you at any time before, during, or after attempting to follow the directions in this Instructable. Work and play safely, friends.
Step 1: Do Some Planning
The first thing we need to do is figure out how much wire we need to end up with the correct length of finished cable for our tree. Here’s how I figure this out:
- Decide how tall you want your tree and add 4” for the roots. We’ll call this “T”.
- Decide how many branches you want - this also determines how thick your trunk will be. For this instructable, it will need to be an even number. We’ll call the number of branches “N”.
- Each branch will have 6 wires (2 of each color).
- Your total amount of wire is W = 6TN
- I want a 14” tall tree, so I add another 4” for the roots. That gives me T = 18”. I want 6 branches, so N will be 6.
- The total amount of wire I’ll need is W = 6x18x6 = 648” or 54’
- That comes out to 18' of wire per color.
It’s good to overestimate your tree height by a few inches to account for tree shape and mistakes, so let's say 20' per color.
Now that we’ve made sure we have enough wire and have developed a plan for our tree, we can proceed. These instructions will be based on the tree I’ve described above, so be sure to modify the numbers to suit your situation.
** Six branches of 6-wires each will fit easily into a ⅜” drill chuck. I managed to get ten 6-wire branches into my ⅜” drill, but it was getting a little tight. If you decide you need a dozen branches, you may need a drill with a bigger chuck.
Step 2: Make Your Basic 6-wire Cables
Put all three spools of wire on a dowel, long screwdriver, etc. and have a friend hold the ends of the three wires. Take the spool and go 10' where you'll loop the three wires around a stationary object. For my stationary object, I clipped a spring link ($4 US at big box store) to a door handle and slipped the wires into the link where they would be secure but easy to remove. Return to your friend and cut the wires from the spools when you get there. You now have three 20' wires doubled over.
Twist the 6 wire ends together a few turns so they don't escape. Now make sure none of the wires has any slack and stick them into the chuck of your drill. Tighten securely, making sure none of the wires have slipped into the gaps in the chuck's jaws.
Put on your safety glasses and gloves! Or at least your glasses. The skin on your hands can grow back, but not so much with the eyeballs. Be careful out there.
Take your time with this next part. Stand facing the fixed end of the wire and hold the drill so that the wire is fairly taut. This is important for getting a nice even twist in your wires. Don't throw your weight back like you're trying to land a Marlin, just hold the line taut enough so that it doesn't sag. Press gently on the drill trigger so it doesn't spin too fast. You'll see the wires starting to twist. When you get a nice twist within an inch of the spring clip, stop. Don't get crazy here - you don't want to over-stress the wire. Remove the wire from both the drill and the fixed end. The wire will try to untwist - let it do so while still keeping a loose hold on it. It won't untwist much, but you don't want it whipping around.
Cut off the loop at the fixed end. You have created a basic 6-wire cable.
Here's how to put together your tree trunk:
- Cut the 6-wire cable (it will be a tiny bit shorter than 10' now) into three equal length pieces. I did this because I want to end up with 6 branches. (If you want more branches, either start with a longer length of cable, or repeat the process with more cable.)
- You now have three 6-wire cables that are roughly 40" long.
- Take these three cables and loop them through your spring clip.
- Take the 6 ends and twist them together a little bit.
- Now carefully chuck them back into your drill.
- Repeat the twisting process so you end up with a roughly 20" rope with 36 wires.
- Again, clip off the loop on the end.
You now have a lovely, 36-wire cable that is ready to be used for your tree.
Step 3: Divide and Conquer
Now that you have a nice thick wire rope, it's time to unwind a little. Working on one end of your rope - let's call this the roots - untwist about 4". Yes, all of the strands. Then separate them by color and twist all the like colors together. It helps to use pliers to get a good grip on the wires when twisting the roots.
You'll have three roots - green, red, and copper. Trim any extra long wires from the tips of the roots, so that most of the wires are close to the same length.
Now head over to the solder pot.
Step 4: The Solder Pot
Warning and additional disclaimer! Solder pots are not for children. If you are doing this project with kids always have a second adult guarding the pot! Only one person approaches the pot at a time. Seriously. I hereby take no responsibility for anything that happens between you and your solder pot, or for any other injuries, physical or emotional, that you may suffer while making this project. There. Let's move on.
OK, so fire up your solder pot in a safe place with adequate ventilation. If you knock it over, you'll have molten solder all over. Very, very bad. See warning above. Put on your gloves and keep your eye protection on.
Once your solder is liquid - mine only takes about 10 minutes to get to this point - use a clean stick to scrape out any nasty stuff floating on the solder. The solder should be shiny.
Your roots are showing:
Now dip one of your tree roots into the pot. You'll only need to do the red and the green roots. The copper colored wire is just for show, though it doesn't hurt anything to strip/tin it. Stick the root in far enough so you are sure to get any stray, shorter wires. Leave the wire bunch in the solder for about 15-20 seconds. This gives the solder time to burn off the enamel coating on all the wires - you’ll see/smell some nasty smoke rising from the pot. Now carefully take the root out, let it cool (solder cools pretty quickly) then repeat with the other root(s). Your roots will now be stripped and tinned.
Solder some leads onto the roots:
Next, solder some wire leads onto your red and green roots. I used regular red and green wire for this. You can use the solder pot to do this part if you wish, but since it's regular wire, you should strip it first to reduce the amount of burned junk in your solder pot. I soldered on some nice long 10" or so wires onto the roots so I would have plenty of options for my base.
Step 5: Branching Out
Here's where your artistic self takes over. Move your attention to the top of your tree and start untwisting the wires into branches in whatever way you see fit. I've seen these shaped like Pine trees, Palm trees, ghost trees, etc. Take your time with this and shape it to your taste. Make these with friends, drink coffee and gossip while untwisting your wires. Once you're satisfied with your tree's shape, you can decide on where and how many LEDs to add. On my tree, I separated the wires into 6-wire branches, planning on one LED per branch. Identify two nearby wires - one red and one green - for each LED.
Head back to the solder pot:
Once you've identified a red and a green wire for your LED, go back to the solder pot and dip the wire tips into the molten metal. You won't need to keep them in the pot as long as before, maybe 10 seconds. You can do several at a time, just make sure they don't touch each other since this could cause a short circuit later if you accidentally solder a red and green wire together. **See Important Warning below.
Now test your newly tinned wires in one of the following ways:
- If you have a multimeter, which you probably do if you own a solder pot, use the continuity test function.
- Attach a power source (3 volts would be best for this - either a lithium coin cell or a couple of AA batteries) to the leads you put on the roots earlier. I attached the red root to positive. Hold a known good LED to the tinned tips of your branches. Make sure the long leg of your LED is touching the red (positive) wire and the short leg is touching the green.
If you are having trouble getting connections between branches and roots, try re-tinning your roots.
Solder LEDs onto your branches:
After successfully testing your branch tips, go ahead and solder the LEDs to your tips. Make sure you test the LEDs before soldering, just to avoid trouble later. Most cheap LED assortments will have some bad ones in there.
You may also wish to consider the voltages your LEDs take. Red LEDs are fairly low voltage while greens take a bit more juice. Try to match up your LEDs (voltage-wise) so they won't engage in sibling rivalries. I prefer to use the slow-cycling RGB lights - you can find them on eBay for fairly cheap and they work well together while providing the visual interest of different colors.
I use 3mm lights, but the 5mm lights work well, too. If you want your tree to look like a gumdrop tree, go for the 10mm LEDs and post a picture, please.
If you are using the tin-as-you-go (recommended) method, test your tree after soldering each LED - it's very satisfying. If you tin all at once, make sure you examine every tinned wire to make sure the tinned part isn't shorting your tree. Here comes the warning:
**Important Warning: The first time I made this, I went ahead and tinned the tips of all the red and green wires because they looked nice and so I wouldn't have to return to the solder pot later. This turned out to be a mistake. As I was soldering my LEDs onto my nicely tinned branches, I tried to test each one as I went along. The problem was that some of the freshly tinned reds were touching some of the freshly tinned greens (it only takes 2 to ruin the party for everyone!) and that produced a short in the circuit. So I had to examine the tree carefully each time I soldered on another LED to make sure there was no short. Not worth it. Next time, I'm going to tin as I go.
Step 6: The Base
You'll need to make a base for your tree. Here are a few options:
- a block of wood, hardwood, driftwood, a piece of firewood, etc.
- a rock
- a tray of pebbles or decorative glass thingies
- an empty skull
- you get the idea
If you’re using wood, you might want to drill a hole just below the trunk of your tree and thread your power leads down through it.
This part doesn’t really need instructions, since we’ll all have different bases, so I'll just mention that it never hurts to dab some hot glue on the underside of your roots to help hold it in place on the base.
Oh, and if you use a metal base, you'll need to insulate your root tips.
Step 7: Electrify & Enjoy
Once you’ve gotten your tree secured onto its base, you can finish the wiring. I didn’t bother with a switch for mine, but it would be a nice touch.
Solder the resistor in between one of the lead wires and the power source.
If you are using USB, you’ll need to cut the USB cable near the non-computer / non-charging-adapter end and figure out which wires to use. Use your multimeter to determine which wire is positive and which is negative. Attach appropriately.
I used more hot glue to attach the wires to the back of the base to provide a little strain relief.
Thanks for reading. I know I'm a little wordy, but I prefer to err on the side of too much information. Have fun and be careful! Oh, and post pictures!