Recently I had a large 30 year old ( I have only been using it for around 6 years) light bulb burn out so I decided to make a night light out of it.
I decided to make this a low voltage DC project...
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Step 1: You Will Need
You will have to have basic soldering knowledge and the following materials:
Clear light bulb
quartz crystal that will fit inside of the light bulb
Plastic light socket (home depot sells this for $1.40)
Wall Wart, 5VDC
Regular household copper wire ( about 10 inches)
3 LEDs ( I chose amber DIgiKey part number 160-1653-ND)
150 Ohm 1/4 watt resistor
1 1K Ohm Pot ( this was an old spare with a click off switch on the low side, sorry no part number)
3/8 inch flat rubber washer
Step 2: Prep the Bulb
There are several Instructables which show how to prep the bulb.
I used a bench vise to break the purple glass insulator on the bottom of the screw base.
I followed this with a small screwdriver to break the clear class tube under the insulator the a pair of needle nose pliers to remove any remaining glass.
Be careful and wear safety glasses and gloves when doing this.
Step 3: Prep the Crystal Holder
Strip the 14/2 household wire or just use the bare ground wire from the bundle
Using the small crystal as a guide, tightly wrap the bare wire several times around one end, make sure you leave several inches of wire to attach to the base.
Step 4: Make the Led Light Assembly
Tightly grip 3 LEDs with the flats together.
Bend the long leads(anode) outwards at a 45 degree angle and twist the short leads(cathode) together tightly.
Press the led assembly into the base and bend the long leads so that they touch the copper wire holder. Solder the 3 leads into place onto the holder.
Solder another wire to the cathode wrap.
place the assembly in a vise and fill with clear silicone.
Press the crystal into the silicone and wait for 24 hours.
Step 5: Make the Light
I had to make the opening in the light base slightly larger to fit the LED light inside of the bulb, I used needle nose pliers for this.
Insert the LED assembly into the bulb to get an idea of where you would like it placed, mark the anode (holder) wires and create a flattened part on the wire. I used a bench vise for this.
Bend the wires at the flat spot and place the assembly back into the bulb. Solder the wires to the screw base on the bulb, you may want to use a high powered solder gun for this so that you do not end up with a cold solder joint
Notch the edges of the rubber washer with side cutters and fit over the cathode wire and into the bulb screw base, Place a large ball of solder on the cathode wire at the rubber washer interface.
Test fit the bulb in the base and trim any extra solder as needed
Step 6: Power the Base.
Drill a small hole in the light socket base which will allow enough space for the potentiometer to sit in. The hole should needs to be large enough for the pot shaft to go through.
With the pot in place solder one lead to the 150 Ohm resistor and connect it to the socket screw which goes to the center of the socket for the cathode wire.
Solder the negative lead of the power supply (shown black) to the center lead of the pot.
Attach the positive (shown red) to the socket screw which connects to the bulb screw base mating surface.
Not shown but attach a knob to the potentiometer adjustment shaft.
Step 7: Enjoy the Light
The potentiometer has a built in switch which allows for both on/off function and dimming.
Plug in the wall wart and enjoy the light!!!