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Tarver’s instrument is unique to say the least. I recently spent some time with him to witness his invention first-hand and was taken aback. High above his loft, entangled into the foundation, sits his creation. It is a beautiful expression of do-it-yourself ingenuity that is one part concrete and two parts found objects. The interlocking elements and nautical details distinguish its custom look and feel. Tarver’s ability to reconcile the geometry of its construction proves necessary in achieving musical harmony. Witnessing the instrument being played can only be described as extraordinary.

Tarver, details the precision involved in achieving the sublime resonance which bellows from the instrument:

The main beam was built up with a pair of 2×8′s glued together at the outside edge, blocking a short way in along the joists, a 3/8″ plywood stress-skin bottom, and concrete fill in the cells. The platform is not supported with any post(s) from the ground, but rather suspended from the I-beam in the ceiling with the 2-inch square hollow steel bar. The steel post terminates in a concrete finial which supports eight steel wires that go from corner to corner. The rings which anchor the wires are supported with railway spikes.

A big thank you to all those involved. Check out the rest of the photos on Flickr.


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Comments

  1. dafydd says:

    The platform is not supported with any post(s) from the ground, but rather suspended from the I-beam in the ceiling with the 2-inch square hollow steel bar.

    Yah, I’d never sleep on that bed. What makes anyone here think that roof I-beam was ever designed to support more weight than just the roof?

    That’s just a collapse waiting to happen…

    1. shagdora says:

      I, for one, sleep in that bed and can attest to its structural integrity and stability.

      No problem if you don’t want to sleep there. You won’t be missed.

    2. tarverator says:

      Fear of immanent collapse has not exactly dominated the impressions of those who have seen the structure up close.

      The ledger, the tie-in to the main pre-existing loft, and the steel post support hardware were designed and installed to exceed the building code requirements for a deck of a similar size and configuration by over a factor of two. Neither the concrete in-fill reinforcing the cantilevered main beam of the platform, nor the eight steel tension cables, nor the incidental bracing provided by the shelves and handrails were considered for the basic load calculations of the bare platform (except as so much dead load).

      The ceiling beam, or more correctly roof beam, has stoically withstood the snow loads of a century of Canadian winters. Because of recent weather trends associated with global warming, building codes are being amended to reduce roof snow load requirements. Meanwhile, in many places throughout the former munitions factory where the “flying” loft is installed, other roof beams show evidence of the kinds of big hoists typically found in heavy industrial buildings, the capacity of which is rated in tons.

      The dead load of the platform is perhaps half a ton. Without the tension cables, about half the total load is borne by the ledger and the tie-in to the main loft, and about half by the post hanging from the roof beam. I am not sure exactly how to calculate the density of people stacked like cord-wood, but it seems to me that one would have to invite quite a few friends into bed (nearly two tons of them) before the load on the overhead beam approached even one ton acting straight down — with slack cables.

      But when the cables are tightened, the forces on the top of the post do not just act straight down. The steel post, the tension wires, and the very rigid main beam of the platform form a triangular truss which tries to pivot around the tie-in to the main loft. This results in a moment force pressing the top of the post laterally into the roof beam, enhancing the effect of the bolts. (Remember: bolts act primarily through friction, not shear.) It is even possible that if, when the cables are tight, one were to remove the bolts from the connection between the post and the roof beam, nothing would move unless the tie-in to the main loft failed. Did I mention that I made that connection doubly redundantly strong? Obviously I am not going to try popping the bolts, but it would be fun to set up some mirrors and a laser to detect exactly which way and how much the post and the beam deflect under load.

      So, in a word, it ain’t goin’ nowhere but stayin’ where it’s at. If someone replaced the bed with a marble hot tub, I might not want to stand under it during a blizzard. But so far, the live loads experience in normal use have not even strained the structure enough to perceptibly alter the tuning of the strings.

  2. Gah! says:

    Yeah, thanks for the Yoko Ono concert, now my ears are bleeding.

    1. tarverator says:

      Stuff your ears with cotton to staunch the bleeding.

      Leave the cotton there to prevent re-exposure to known acoustic allergens.

      While recovering, you may wish to select or compose music more to your liking, and contact us with a proposal to perform it. The instrument has a range of one octave — eight strings arranged in Pythagorean progression — and can be tuned to major, minor, or modal scales. Do not feel constrained to use only one string like the impromptu performance showcased in this blog; neither is it necessary to sing in Occitan. Know any Bach?

  3. Peter Jones says:

    Tarver did not realize he was building steampunk at the time. The bed loft was constructed in a way that best suited the context of a 100+ year old concrete factory building with iron-framed windows, massive beams, and strong bits of cast-off. It became a musical instrument from the affordances of the structural necessity. It was not designed as a steampunk instrument at all – but it evolved that way due to discovering the affordances of the construction and the problems solved along the way. A reading of the history of great inventors in the original “steam” era shows that serendipitous problem solving, not planning, was the key to breakthrough.

    Because a steel wire truss strengthened the suspended frame, the wires were taut and therefore tunable. The turnbuckles were added later to tune the wires, then the bridge was constructed to enable its tuning to keys. The soft resin-coated mallets were created to strike the strings gently.

    And while it would be wonderful indeed to have Yoko perform here, we enjoy the jams that evolve from people figuring out their own way to play the bed. The video shows a more percussive approach, but there are many ways to elicit felicitous tonality and rhythm.