This project is from the collection at http://www.bigclive.com
Step 1: Getting the Bits Together.
You'll also need some miniature sockets for the LEDs. I used standard Molex style sockets with a 0.1" (2.54mm) pitch. These are actually designed for interconnecting PCBs, but they also make great LED sockets. They are supplied as a plastic shell and individual contacts that click into place once you've attached the wire.
You'll need some resistors that will depend on the voltage you are going to use the display at. Typically 330 ohms for up to 9 volts and 1000 ohms for up to 18 volts. Normal quarter watt carbon film resistors are ideal.
Some heatshrink sleeving is good for covering the resistors with. It makes them look neat and keeps them from shorting against each other. Choose a sleeve that will slide easily over your resistors. Typically about 3mm (about 1/8th of an inch) inside diameter.
LEDs. Any type shape and size as long as the leads are on 0.1" / 2.54mm spacing. Diffused LEDs will give bright dots of light on the ornament while clear LEDs will project random splashes of colour around the room. Choose the brightest LEDs you can find. Ebay is a good resource. Don't worry if you get some cheap LEDs that fail, 'cos you can just plug in a new one in seconds!
Finally choose a suitable power supply. This could be a battery pack or a plug-in mains adapter. The adapter doesn't need to be regulated, so you could use a general purpose one. You could even run the effect from a solar power supply like the ones used for outdoor solar garden lighting.
Step 2: The LED Sockets.
The shell is stock number:- 22-0905
The crimps are:- 22-1096
For reference the wire I used was:-
Red single core:- 01-0335
black single core:- 01-0300
Step 3: Soldering to the Socket Crimps.
Fortunately the terminals are quite easy to solder to, and they still fit into the housing OK even when not crimped.
I found it easiest to clamp the terminal gently in a small vice or one of those "helping hand" devices with bendy arms and crocodile clips. Put a touch of solder (preferably the good old fashioned lead based stuff) into the wire grip area as shown in the picture, then strip the wire by about 3/16" (5mm) and after tinning it with a touch of solder, apply it to the terminal and reheat the terminal with the soldering iron so that the solder flows around the wire. Hold the wire in place after removing the soldering iron to let the solder cool down and harden.
Be careful not to let the solder flow into the contact area since it could stop the contact from working properly.
Don't worry if you mess up a few contacts. They are supplied in bulk!
Step 4: Adding the Resistors.
Cut the wire about 2" (50mm) from the end and strip and tin both ends. Cut one lead of the resistor down to about 3/16" (5mm) and tin it with solder. Keep the other end full length to give you something to hold onto as you solder the other end. I tend to clamp the wire into a little vice or clamp and then apply the tinned end of the resistor to the tinned end of the wire and reflow them together with the soldering iron. Once one end of the reistor is soldered to a wire you can crop, tin and solder the other end to the other part of the wire.
Once the resistor is soldered inline you can slip a short length of heatshrink sleeve over it and shrink it on with the careful use of a heatgun or other source of high heat.
The resistor will limit the current through the LED. 330 ohms are good for up to about 9V and 1000 ohms are good for up to about 18V.
Step 5: Inserting the Contacts.
The housings usually have pin one marked with a number "1" and I tend to make that the positive connection.
Don't worry if you put the contact in the wrong place, since you can remove them by carefully pushing down the little spring lip in the window and then sliding the contact back out. If you push it down too hard and it doesn't spring back up again, you can gently tease it back up with the tip of a sharp knife.
Step 6: Commoning All the Wires.
Step 7: Twisting Wires.
In the picture I have also added a common power supply wire to each common joint and sleeved them with heatshrink sleeving. You could attach the wires directly from a plug-in power supply like this and wrap them in insulating tape if you desired.
Step 8: LEDs!
It's also useful to mark the socket with a dot of red on the positive side and/or black on the negative side. A standard marker pen is suitable for this.
Step 9: Test.
If an LED doesn't light then you may have inserted it the wrong way round. It's unlikely to have been damaged by the wrong polarity and should work when you turn it round in the socket.
Now just place it in a dark corner and marvel at your creation.
For extra style you can wrap the wires round a pencil a few times to give them random spirals.
Try the colour changing LEDs in this ornament. They look very psychedelic.