Okay. Long story short, I spent half of the day Saturday(2/6/10)working on a single key with the bench grinder buffer until @factoid finally realized that I had been using the wrong buffing compound. It was a laugh for him, but it only made me mad. so we walked down to Baller Hardware and got another type of compound(this one was brown), and it worked a little better, but it was messy, and soon we had brown splatters all over one of the walls. I spent the rest of my day working with this. At the end of the day, I was still working on the same piece when @factoid came over and said that it wasn’t the compound, it was the machine I was using. Another laugh for him. So Sunday(2/7/10)I started using another tool that maybe is not as easy as the bench grinder, but definetely faster. Here are a few pictures of me using it.

picture #1-This is a picture of me using the new tool.

picture #2This is a good shot of the tool itself. As you may have noticed, we have built our own custom jig to hold the metal piece in place.

picture #3-This is a picture of a half-finished key.

We cut more keys this weekend. We’re up to F#. Almost one out of the four planned octaves of keys is cut (but only half of the keys are tuned so far.

Since the metal heats up during cutting, and heated keys resonate a good half-tone lower than room-temperature keys, you’re forced to put them aside until they cool down before trying to tune them. It’s time-consuming work – each key can take up to an hour to cut and tune properly.

We also spent a lot of time figuring out the polishing/buffing routine and tools, but I’ll let @alienrobot tell you about that.

We bought some aluminum bar (3″ x .5″), which has a nice, resonant tone without any nasty harmonics to it.

Also, it’s the lightest choice (brass and steel are MUCH heavier), which will become important when we have close to a hundred pounds of keys, steel framing and audio pickups hanging off the van.

I learned how to choose raw materials for this project eight years ago the first time I built a xylophone (this one), after downloading these instructions.

I spent a good deal of time hunkered down on my knees, balancing odd bits of aluminum, steel and brass on balled-up socks (per Jim Doble’s excellent instructions), whacking it and listening to it – which gets you stared at, but generally dismissed as not worth calling the cops on.

Eventually, you figure out what sounds best – and off you go.

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