Last week, Make posted a link to a doorbell that I saw a few years ago that got me thinking. The doorbell — an exposed electromagnetic solenoid and two wine glasses — is basically just the mechanism from a standard hardware store doorbell with wine glasses instead of the metal xylophone-style (or metallophone, for the picky) bars that make the ding dong noise.
Upon seeing that, I thought it was rather neat, and tried to come up with something I could make that would be similarly cool, and far less pricey. In the course of random shopping, we found a singing bowl with a pleasant note; and it made the perfect candidate for a doorbell mod.
So we bought that, a wall platform at Cost Plus, and a cheap electromechanical doorbell at the hardware store. I think the total cost came out to about $70. It turned into this:
It really wasn’t too hard to make; it’s not the prettiest thing in the world, but it sounds good, and is enough of a doorbell to make the dogs go nuts when they hear it.
Here’s how I did it:
First, I figured out where the bowl and solenoid should fit on the platform. Since this was going into a corner of the kitchen, the solenoid could go on the back left and be less visible; then the bowl could sit towards the front and be the center of attention.
I used Quakehold Museum putty to stop the bowl and cushion from sliding around; the cushion is made of an almost silk-like material and is very slippery. The bowl will slide around and move away from the solenoid with each ring if you don’t do something like this.
I took apart the hardware store doorbell and pulled out the solenoid; it was mounted in place with a small rivet, so I just drilled it out and pulled it free, bringing the two clapper plungers with it.
Then, I used an L-bracket, a small piece of hardwood, and a screw and nut to build the holder for the solenoid:
After that, it was just screwing the L-bracket down to the platform, connecting the two wires, and putting the cushion and bowl in place. The solenoid ended up in the rear corner next to the wires coming out of the wall:
The last important bit is placing the bowl. Distance can be crucial; too close, and the plunger will stay touching the bowl after it strikes and mute the sound; too far, and the plunger will shoot out of the solenoid when it releases. After some experimentation, it turns out that if you slowly push and release the plunger on your own and let it go as far as it’ll go under just the spring’s power, then place the bowl just barely past that point, you’ll get a consistent sound each time.
Here are a couple more pictures of the solenoid and bowl:
And here’s what it sounds like:
The whole project was pretty easy — apart from the wiring (our house had no doorbell before this, so there was some attic-crawling and wall-fishing, but by this point I’d run cat5 through most of the house, so I was pretty good at that bit), it took about half an hour to put together and get working.
Of course, here’s the obligatory picture of the doorbell button: