Intro: LED-based Faux Gas Lamp
Our old house still has some of the original (now disconnected) gas lines stubbed out on the walls. I was thinking of how to make a relatively realistic looking gas lamp without having an electrical cord dangling from the fixture. Having done a previous Instructable using hacked LED tea lights, I decided that flickering LEDs might hold the answer.
Step 1: Materials
LED tea lights - obtainable at most craft, and decorating stores. I've even seen them in bulk at warehouse stores. We're only interested in the LED component from these tea lights. I haven't been able to find a source for the flickering LED components themselves, so tea lights seem to be the easiest way to obtain them. For this Instructable, I used three yellow-colored flickering LEDs.
Additional LEDs - Experiment with different colors, brightnesses, etc. to get the effect you like.
Gas light fixture - I found this one on eBay and cobbled together some other gas lamp components that I had already. The gas light fixtures mostly use the same screw thread size (US 1/8 in pipe thread), so mix and match to get the look you want. Gas light parts can be bought here: http://www.acrosstheboardwoodwork.com/
Candle-type light bulb - I used a burnt-out frosted CA-9 (flame shaped) bulb. (The frosted ones seem to be getting hard to find with the standard-sized base, but still can be found in the smaller chandelier base.)
Jar lid or something similarly round which can serve as the base of the lamp.
Black paint (to paint the lid black)
Step 2: Disassemble the Tea Lights
There are a variety of different models out there. Some have a slide switch. Some turn on and off by rotating the base. In any case, since we're just interested in the LED component, pry apart the base of the light and desolder the LED. If it's the type with the slide switch, keep that as well as it would be useful as a switch for this Instructable.
Step 3: Disassemble the Light Bulb
I've found that this type of bulb is notorious for the glass coming loose from the base. When changing burnt out bulbs, they often end up separating from the base if not unscrewed carefully. Of course, the one I used for this project was still well-cemented to its base. To separate the glass from the base, I find that holding the bulb and carefully moving the base around is enough to loosen the cement. (Remember eye protection and gloves!) If not, crushing the glass under the center connector at the very end of the base with pliers is usually sufficient to loosen things up.
Once the base is off, carefully push the glass stem holding the filament to one side the break it off. Remove it and the filament. You should have a large enough hole in the bottom of the bulb to insert the LEDS.
Step 4: Test and Assemble the LEDs
For this Instructable, I was going more for mood lighting than raw lumens, so I chose to use three flickering LEDs connected in parallel. Combining flickering LEDs with continuous LEDs would create a brighter light that still flickered a bit.
Experiment with different components to get the effect you like. The photo shows the three LEDs connected in parallel. LED leads were insulated further to prevent shorting. Power leads were left long enough to run out of the bulb and down to the battery.
Step 5: Build Base and Assemble
I didn't want to have to cut any of the original gas fixture which made fitting the LEDs into the glass bulb, and the bulb onto the fixture a bit more troublesome. Cutting the gas nozzle down in height would make it easier for those less compulsive.
Fortunately, the opening in the base of the bulb was wide enough to accommodate the 1/2 in. diameter gas nozzle with room to spare to run out the wires. To hide the wires, I cut a 1/2 in diameter hold in a jar lid I had sitting around, and painted it black. This serves as a base for the "flame" and sits well above the shade holder, so it is not very visible once the shade is on the fixture.
Placing the LED assembly into the bulb, and holding the power wires against the side of the hole in the bulb base, I pushed the bulb down onto the gas nozzle making sure that the LED assembly sat above the end of the gas nozzle so that they wouldn't cast shadows of the nozzle.
I soldered one of the slide switches from the tea lights onto the end of one of the power leads. I used a CR 2032 3-volt coin cell as a power source. To attach it to the power leads, I used the same technique I used in my earlier "Levitating Candles" Instructable. The two power leads are held onto opposite sides of the coin cell with a piece of heavy paper or cardboard. A binder clip is then placed over the cardboard to hold the leads in place. In this case, I removed the "legs" of the binder clip to save space.
I'm not sure how long this lamp will run on one CR2032 battery (It will power one LED for over 8 hours.), but there is enough room in the base for a AAA battery or two if need be. An advantage of the CR2032 battery is that a current-limiting resistor is not needed when powering LEDs. Using a bigger battery will likely require a resistor to prevent burning out your LEDs.
Step 6: The Finisished Product
I screwed the fixture into the gas line stub that has been mocking me all these years. I added a Victorian-style glass shade and turned it on. It gave off a warm and flickering light; the perfect ambiance for a Victorian house without all those nasty gas fumes.