We started out at Home Depot, looking around for suitable material to make the chimes from. I've made them from wood and copper pipe before, but Megan wanted these to be gold or bronzy in color. We couldn't find anything like that at the store, so we settled on some metal conduit and got some metallic gold paint.
In my other chimes, I'd just cut up the pipes in monotonically increasing lengths, drilled holes at the top, and called it a day. It turns out, however, that there's some science behind doing it right. First, you need to decide what notes you want them to sound. Apparently the pentatonic scale is pleasing to the ear, so we went with that. After some searching I found some directions that explained how pitch can be obtained by adjusting the length (frequency = 1 / length^2).
You also shouldn't just drill holes for the support strings willy-nilly. There are particular points at each end (22.4% of the way along), called the nodes of vibration, which are the axis points at which the there is no natural motion when the chime is vibrating. Drilling the holes here lets you support the chime without interfering with its sound. I'd never noticed it before, but you can easily test it by just striking a piece of pipe while holding it in the right place or the wrong place with your fingers. The location makes all the difference, determining if you get a nice tone or a dull plonk.
Here's the numbers we used:
Ok, after all that, we cut down the pipe, which wound up sounding surprisingly nice for what it was. Some scrap wood made up the other bits. Megan and I painted half the chimes gold, left the other half silver, and painted the wood purple. A very Megan color palette.
And here are the chimes in action:
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