Tech Menorah

Having a Christmas tree, I got requests for a menorah. I realized that programming it would be the easy part, and the only idea I had for the candles were transfer rollers. Transfer rollers are used in laser printers to put toner onto the paper. Sometimes they’re separate; sometimes they’re in the toner cartridge. And seeing as how they’re shiny, I sometimes save them when I get the chance.

The only color I had nine of was purple, and eight of them were smaller than the rest. (I think the smaller ones came from two Dell color lasers.) So I used a larger purple for the shamash. The first step was removing one of the gears from the “bottom”. At first, I just melted them with a heat gun until I found a method of heating them enough to pull it out with needle nose.

You can buy yellow and orange LEDs that blink randomly so you don’t have to code flickering lights. I settled on using a solid yellow and two blinking yellows for each flame. I wired them in parallel so each flame only had two wires. Eventually when hooking up the arduino, I wired the candle grounds on each side together so I only needed two ground connections on the arduino.

My process for making the flames was covering the LEDs in hot glue. I globbed a decent amount of hot glue over the LEDs, stabilized my heat gun, and repeated held and shaped the ‘flame’. Sometimes by removing some of the hot glue, sometimes letting it drip. Note the silicone finger protectors. They’ll protect you from some of the heat and hot glue will stick to them, but it flicks off easier and faster than if it was on your fingers.

Now to the base. I have very few pictures of my woodworking. I don’t consider myself a wood worker, and I winged a bunch of things. I found some pieces of walnut in Bob’s basement. Had I known how difficult it can be to work with walnut, I might have chosen something different. The base is basically a triangle piece with a flat base. (I learned to use a router table for this project – woo hoo!)

I went through a lot of calculations for the depth of the candle holes and their spacing, considering the shamash transfer roller was a different width and height. I wanted an even spacing between them and the tops at the same angle as the base. And then I made a scale model in Coreldraw using those calculations to double check. Standard Forstner bit sets have the sizes for the candle holes. I put a piece of painter’s tape on the bit to know how far to drill.

I thought it was looking kind of plain, so I designed a Star of David to laser engrave on the front. After it was done, I decided to stain it. Like I said, I winged some things.

Looking at the mess of wiring on the back of the menorah, we have a standard Uno on the right. I set the dates and times of sundowns during Hanukkah so it could light the candles at the right times and in the right order. On the left are some test buttons. One simulates day eight of Hanukkah, the other sends a flourish across the candles for a connection test. In the center with the battery is an RTC chip that holds the date and time when the system is powered off. If you look closely, one of the lines to candle three came out. I might end up covering most of the back with liquid tape.

Making its debut in December 2023

My test buttons:

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