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DooBeeDooBeeDoo · #1 (**permalink**) 04-14-2008, 05:57 PM

Okie-dokie, folks. I've finally come through as promised and made progress on this thing. I apologize to you all for my silence... I had a brother-in-law pass very suddenly and have spent a lot of time out-of-town with the sister(s). Enough said.

Phase One - Self-Enclosed Light Source
While the following instructions are within code for the common homeowner, DO NOT work with electricity without understanding basic electrical safety!
Today I started with building a flourescent tube assembly that will fit within the rotating "gobo" tube to be built around it later. It was important to my design to create a light source that was long & tubular but not restrictive to building things around it, therefore I had to cannibalize a 4-ft. flourescent tube fixture and totally enclose one end while freeing-up the other. In escence, a lightsaber prop (NOT to be swung around as such!!!)

I went this direction to stay true to the home haunter's budget and skill. I looked into designing a bushing-driven assembly like you find in barber poles and dance lights, but that would have been both cost- and skill-prohibitive for the "target audience."

Eventually I'll have to build a duplicate, as my theory is based on a rotating gobo on each side of the walkway, but I'll expound on that later.

Let's begin with the parts. Seen below (pics 1 & 2) are the guts & ballast from inside a standard household 4-ft. flourescent lamp (Lowe's, $16... I saved the housing for later if needed), a 34w tube (elec. supply house, $1.50) and a protective tube shield with end enclosures (supply house, $1.50). Also on hand were some extra lengths of 14-guage ("AWG") wire and a dozen 16-to-14awg "end-to-end" bus wire connectors (together about $4). Tools at this point include a drill and 5/16" bit, wire cutters & crimpers, and electrical tape. All told $23 so far, besides tools. Not bad.

I drilled a hole 2 inches from each end of the shield tube (pic 3), then ran my spare pair of wire from that hole down the rest of the tube and out the other hole. I then inserted the lamp tube down through this, and pulled the wire taut so it followed down one edge (sandwiched between the lamp tube and the shield tube with a few inches of wire poking out of each hole). I then (pic 4) stripped the ends of the wire and crimped bus connectors onto their ends. NOTE: many of you may doubt the safety of this, but I have it from 2 Master Electricians that, while uncommon, is perfectly safe with no heat issues unless the wire itself is damaged. By the way, please use only 14 awg or larger as extension wires... DON'T use smaller wires as they WILL heat up.

I cut the "holder ears" off of the ends of the blue & red pairs of the ballast. I popped the end-cap onto one end and then, using some leftover red wire, I sripped & crimped them as jumpers (5 & 6) from the hole extension wires to the ends of the lamp itself. Yes, you can crimp blue 16/14 awg bus connectors right to the ends of the lamp, but be very careful not to squeeze too hard or pull the pins off!

After taping-off that end, I crimped the long red leads from the ballast to the other ends of my extender wires (the other ends sticking out of the other holes). I stuck the other end-cap on and crimped the remaining blue leads to that lamp-end (pic 7) and taped it securely together. All that was left was to sacrifice an extension cord end and wire-nut it to the black & white power hookups.

(8 & 9) As you can see, this gives us a very cheap light source with one end completely free and the terminal end very workable.
Time involved so far = 1 man-hour

I'll be updating you on the rotating gobo ASAP, as well as on the overall design of these units together with the walkway and hall.