Rob Power
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Building a Glass Marimba
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These are the steps I took to build a 3 octave glass marimba (F3 - F6)
Please feel free to contact me with suggestions or questions.
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Day one: picked up some 5mm plate glass.

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Using scrap glass to experiment with widths. Width doesn't affect the pitch much, but it does change the tone (and harmonics) a lot.

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Blanks are cut in three different widths.

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The glass is tuned by shortening the length.

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Sanding the edges with a rigged-up wet sander. The water keeps the glass from chipping and reduces glass dust. Ain't nobody got time for silicosis.

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Fine tuning with a diamond wheel and again lots of water. I bet you're wondering how I took ths picture.

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Safety and fashion go hand in hand.

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It took a few days to sand and tune all the glass.

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Next step is to cut the resonators. They will amplify the sound. Most of them will be 2" central vac pvc, and the larger ones are 3" sewer pipe.

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Soaking the labels off the end caps are one of the most exciting tasks. I'll be sure to post the video.

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The tubes are tuned by length. (Geek alert: when capped, the tube length is one quarter the length of the sound wave. They need to be a bit short (sharp) to account for 'end correction' at the top of the tube).

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Fine tuning the tubes with a bandsaw.

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Matching each tube with it's glass to make sure that the sound of the whole instrument is consistent. If the tube length is a bit off it can cancel the resonance and deaden the sound.

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Cutting and tuning the tubes took a few days. Time for a pint.

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Next step is the frame. I needed a really level surface, and I don't have a workshop, so off comes the bedroom door.

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Lining up the glass bars to create a map. This will make the rest of the project a LOT easier.

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The glass bars must rest on their wavelength nodes, which will determine the shape of the frame. There is a formula for finding the nodes (22.5% length), but a few salt tests confirm that the glass is behaving as expected. As you tap the glass, the salt lines up on the nodes. Are you still reading this?

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The nodes are dotted on the map.

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The rail positions are drawn up under the nodes.

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Rails are cut to the right shape. The cat is wondering why he hasn't been fed in days.

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Making the legs for the end pieces of the frame.

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Legs and top supports are done.

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Assembling the end pieces.

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End pieces done. Wheels will go on later.

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A second pair of eyes keeps things lined up. He is also too hungry to stand up.

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Lining up the resonators on the map.

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The tubes are joined by drilling holes in  aluminum slats. A few bends in a vice are needed too.

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Everything is assembled and it's a huge relief to know that it all lines up.

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The process of sanding and varnishing the frame takes a few days. As it turns out, this is NOT VERY FUN.

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Now the final touches. Wheels are attached, and some layers of foam rubber padding are put on the rails.

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The glass bars are attached using adhesive foam weatherstripping.

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And it's time to play!

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If you build it, they will come. Maybe.