Introduction: Flashlight Bulb Socket for EXPERIMENTS
Flashlight bulbs are common, easy to find, and inexpensive (especially in bulk), but they are a pain in the neck to attach wires to, which somewhat limits their use in assorted hobby projects, especially when children are involved.
The picture shows a "socket" that will hold a normal "flanged" flashlight bulb (somewhat) securely in contacts with normal wire. I'll try to get more "process" pictures if I can find my tongue depressors, but the finished-product photo should show most of what you need to know...
Step 1: The Issues!
Here's a picture of a flashlight bulb. In a typical "real" socket, a spring of some kind will push one connection into contact with the nipple on the bottom, while simultaneously pushing the flange against the second contact. Thus both connections are under tension and will make good, reliable connections.
Traditionally, one wraps a wire a couple time around the base, which works "ok", and then uses tape to hold the nipple against the end of a battery, which works NOT so well.
Springs are good, but generally hard to find in whatever size you actually need. "Springy" metal tends to be difficult to work with. You can solder wire to the nipple, but that's a pain, not really that reliable, makes the bulb non-replacable, and isn't appropriate for younger children.
Step 2: The Socket
You'll need a tongue depressor, a rubber band, and some solid wire. The wire here is from cat5 ethernet cables, which get thrown out by the cartload cause they're too expensive to have a highly paid networking engineer untangle them after they've been used once. (grr.)
So, you take your tongue depressor and cut it in half. Near the end of one half, drill a hole that the glass part of the bulb will fit through, but not the flange (typically, this will be between 3/8 and 7/16 inch.)
At the end of the other side, put a couple notches to hold the wire in place and wrap one wire around at least twice.
Wrap the other piece of wire around the bottom of the glass bulb, just above the flange, and twist it onto itself so it stays.
Stick the bulb through the hole in the T.D. so that it pushes the wire into contact with the flange. Position the other half of the TD so that the bulbs nipple is wedged between the loops of wire. Secure the pieces together with the rubber band, which provides spring-like tension.
Ta Da! Done!
I figure a teacher or instructor or parent with access to tools like a "clamp" and a "drill press" could cut and drill a couple of hundred of these in an hour for minimal cost. Go slow drilling the tongue depressor; they're thin and weak and tend to split. I bet a LASER CUTTER could do the job really well!