It works. More to come.
Category Archives: Instruments
Veering off into left field – to build a marimbula
This is a long way from xylophones and propane-tank drums, but I’ve really enjoyed building cajóns and – for the first time – a marimbula.
The marimbula is a Caribbean instrument, descended from the African kalimba, and generally functions as a bass. As you’ll see in the video at the bottom of the post, I first experimented with a 6-key marimbula built onto the back of one of my cajons, just to figure out the basics of construction.
This one is a 16-key marimbula – which I’ve decided has about three too many bottom-end keys and perhaps one too many high-end keys, as the sound quality falls off quite a bit at the ends of its scale. Next, I might try building one like a piano keyboard (with two layers of keys in white and black) centered in the middle of this scale.
The tuning has been kinda challenging – I finally settled on D – but I’m tuning it slowly by ear because the digital tuning apps can’t handle all the overtones it puts out. Anyway, it’s a helluva lot of fun to play – particularly on a nice, resonant wood floor – because it’s easy to play, and the notes send vibrations through your butt and up your spine. I take great satisfaction in building instruments that create physical joy along with pleasant music.
I use white birch finish plywood. I cut the box pieces through masking tape, which makes for clean cuts by keeping the blade from shattering the delicate veneer. 
Dry-fit the pieces, then drill for pegs. I cut my own from 5/16″ dowels, which makes for cleaner joins than you get with factory-made pegs. 
Glue all the plywood points, then add some glue to the peg holes … 
… and drive them all in. I’ll sand off the excess to make them flush with the surface when everything is dried. 
Being short on (pricey) carpenter’s bar clamps, I use the two I have, then augment with ratchet straps. The vertical chunks of scrap plywood keep the straps from damaging the veneer. 
This is deeply embarrassing as well as horrible-looking: I failed t set up the router correctly, then dragged it straight through the face of the box instead of nicely rounding the corners. After much cursing and shouting, I just capped the whole gashed end with another layer of plywood. 
Laying out the keys and the bridge pegs, and trying to decide whether to use the black anodized finish found on these scraps of spring-steel shipping strap, or polish it and use the moiré pattern left by the tools. 
The bridge is a strip of red oak. I clamped a ruler to it to guide the router, which I used to cut a groove for the bridge’s nut bars (terminology?) to sit in. 
The completed bridge pieces – red oak, stainless-steel nut bars (which the keys will rest on) and a carefully-drilled-out rod of aluminum for the bridge, which will clamp the keys down to the nut bars. 
I cut a piece of 1/8-inch birch ply for the face, then drilled it out and mounted the bridge assembly (traditionally called the harp) to it with machine screws and wing nuts. 
Here’s a comparison of the 16-note bridge with the 6-note bridge I mounted on the cajon that I used as a test mule. 
After masking the face to prevent splintering, I laid out the sound holes, then cut them with a keyhole saw (for the smaller ones) and a roto-zip bit on my knockoff Dremel for the two largest ones. 
Next, I drilled all the holes for the screws – way too many, it occurred to me way too late, but the large number of screws actually wound up helping the overall visual design. 
I masked off the edge for painting. 
Earlier, I cut the shipping strap chunks into rough lengths with an angle-grinder, then ground the corners round … 
and smoothed them with a wire wheel. 
Shot the masked instrument body with red enamel (a favorite) 
… and screwed on some little rubber feet to protect both the floor and the wood, since you’re meant to sit on the instrument to play it. 
To add a little bit of drama (and filter out toys, crayons and Cheerios that younger musicians might be tempted to insert in the sound holes, I spray painted some metal fabric and glued it to the backside of the face with Liquid Nails so it wouldn’t buzz when the instrument is played. 
Et voila. 
Building cajóns – all of a sudden
The old-timey title for this post could have been:
The Wisdom and Benefits of Contemplating a Temporary Shift from the Traditional Norm for This Institution in Materials, Methods, Design and Construction of Multi-Purpose Acoustic Percussion Instruments:
Or, a “Box to Bang On”
Because this post is about a kick in the head. A total world-shifting creative non-sequitur from all this demanding, burly, unforgiving metal I’ve been working with for so many years.
All of a sudden I’m building cajóns. Out of wood. Where did *that* come from.
Lemme back up a bit.
I’ve been goofing around with the idea of combining disc gongs with a sound box like the one I built a million years ago for my very first xylophone.
I wanted to explore: disc arrays, resonance, materials, instrument playability.Here’s a sketch: —->
And then it occurred to me that the cajón (a sit-upon box drum with  roots in Peru and on loading docks everywhere) is such a perfect blend of structural integrity and resonance – like musical furniture – that if I could build one strong enough, it could do double duty as both metallophone and drum.
Gee, that sounds like a lot of work.
Maybe just start with building a good cajon to see if it’s easy enough. So, after digesting half a dozen how-to’s on YouTube and stealing some of the most interesting design ideas into my plan, I started my first.
Here’s a ragged build log:
Percussion cruise to Sonic Runway and beyond
A percussion cruise is a pretty simple pleasure: Invite people onto the roof to play the drums and gongs, and drive across the Black Rock Desert.
As I drive, happy sounds drift down – people lazily striking the gongs, and chatting passionately about their burns.
The first part of this clip is the sound of a cruise we did on Tuesday afternoon, and the latter part is part of XyloVan’s set at Sonic Runway – friends from Liminal Labs joined random Burners on the roof and around the xylophones to play.
Unfortunately, the mixer crapped out so the roof percussion drowned out the xylophones, but the sound was enough to trigger some beautiful patterns on the Runway.
Tonepod 2 – A new, more-portable hank drum design
(edit: I quit Facebook in 3/2018, which accounts for the missing videos.)
So, I make these musical drums out of up-cycled propane tanks. Click through for a demo video (and the build log) for Tonepod 2, the new model. Making this one, as with the others – gave me tremendous joy – which is good because the process takes about 40-60 hours and fills our basement shop with dust and noise. And yes, I might be able make one for you. Inquire here.
At this point, I have already safely emptied the tank of propane and washed out the residue of methyl mercaptan (the nasty stink agent that lets you know when odorless propane is leaking). (Seriously, don’t use any tool on metal until the propane is safely gone). I’ve cut off the handle from the top and the base ring from the bottom, and ground off the welds, and now I’m grinding off the rest of the paint before cutting … Continue reading Tonepod 2 – A new, more-portable hank drum design
#7 – the Rat Rod
I’m not much of a player, but here’s a demo of a drum in C-minor – This is the seventh drum I’ve made out of a 20-pound propane tank.
The discarded tank came into the shop in a thrashed, rusted-out pale blue, which looked amazing.
So I kept much of the original paint, cleaning off only a ring of the steel at the tips of the tongues. I then added a pinstripe ring around the hexagonal key (low-C) in the center, painted on a stylized “7”, which I limned in Sharpie – and sprayed 3 or 4 coats of clear enamel over the whole thing.
I made two major design improvements for sound – I cut out a resonator hole in the tank’s bottom (around the valve, just inside the handle).
And I’m experimenting with a new deadening material – recycled bicycle tubes wrapped around all the way around the tank to keep the body from ringing and drowning out the keys.
So far, so good!
Fireball XL-5 – the build log
I made Fireball XL-5 for Mykal Burns, a video producer, roller derby enforcer and erstwhile percussionist. The build went something like this:
If you would like me to make a drum for you on commission, the price is $300 – $250 if you bring your own empty propane tank. Contact me for details.
“Green Destiny” – How to build a propane tank drum
If you would like me to make a drum for you on commission, the price is $300 – $250 if you bring your own empty propane tank. Contact me for details.
Gongs all made!
Just a quick one – these are the gongs we made for our Indiegogo supporters, all engraved and ready for their fittings. It’s not too late to get one of your own! A $150 donation to our big Burning Man project nets you a hand-engraved gong with your slogan Or inspirational quote of choice, a dowel chime, machined aluminum block pendant and slice pendant, crew patch and sticker. Just Paypal us at factoid@well.com and tell us your inscription in the comment field and we’ll get right to work on it for you! Thanks so much to all our gong-level Indiegogo supporters!
Check out the demo video!
Bits and bobs – 3 days till liftoff
Because an art car is never finished.
I disassembled all the light arrays from XyloVan 1.0, and I’m reassembling them onto the light bars I made for JANUS. This involves testing all of them, including the flasher circuits …
… and then screwing them down. I’ll wire everything up later today. (It’s stupid-o’clock in the morning right now).
I also cut a stencil so that I can spraypaint warnings (PLEASE DON’T CLIMB HERE!) that discourage people from trying to scramble up onto JANUS’ “shoulders,” which are built to withstand the playa winds and sun, but not a 238-pound Java developer full of Fuzzy Navels and good cheer – let alone a 5-year-old child in a Wolverine costume.
I then cut a frame for the stencil out of an old TV carton and put the whole thing together with Gorilla Tape (accept no substitutes!)
I’ve also been drilling out a few discarded xylophone keys that I plan to mount with the drums that will be installed on the Cloud Deck so that people riding on top will have more instruments to play.
Chugchugchug.