Harpsichord

And is playable.

Specifications include a 1 x 8' disposition (single choir (one string per note), middle C corresponds to middle C on other instruments), single manual (one keyboard), 61 note range (5 octaves, C-c'''', A415), 6 x 3 ft. dimension, approximate 150 lbs. weight, and an estimated 100,000 LEGO piece count.  The strings (brass gauges .012-.018 and steel gauges .008-.012) exert approximately 325 lbs. of tension.

The important considerations during design were strength, efficiency, and durability.  Anticipating the tension of the strings, the instrument had to be built strong, yet be able to incorporate the functions and mechanisms on a lifesize scale.  With many moving parts, it also had to withstand the repeated demands of a keyboard instrument.  Several prototypes of the various sections were made.  After finalizing designs, I started amassing the necessary LEGO parts.

Also,

Acoustically, the instrument would benefit from being as smooth as possible, so instead of having the standard LEGO studs exposed, I covered them up with tiles (smooth topped flat pieces).  Besides the functional studs that align the strings on the bridge and nut, no external stud is untiled.  Likewise, the entire unseen floor of the soundchamber is decked with hundreds of

Some of the more whimsical LEGO elements were integrated as well:

Mosly these were ordered in bulk from

The casing was made next.  This was standard building.  Well, the bentside was done with

The soundboard and wrestplank were built laterally in relation to the casing--the studs face to the side.  This was done in order to preserve the smoothness of the bricks' sides and to counter the tension of the strings--with this design, as the strings pull they hold the soundboard and wrestplank together rather than ripping them apart if built otherwise.  Technic parts were used to secure these directional changes of the studs.  As the bridge is mounted upon the soundboard, reasonable speaking length (the distance between the bridge and nut) recalculations called for several revisions of that entire section.  Then it was locked into place as the case continued its building.  The lid was constructed, but removed to enable easier access for stringing.

LEGO as a medium holds rather well, not to mention is heavier than hell on a compoundedly large scale.  This weight is what holds the parts together and ultimately handles the tension.  During stringing, as I cranked the tuning pins, often I'd hear a disturbing creak off in a corner.  I'd check the case, soundboard, and wrestplank for faults as there was the fear that the whole thing would implode.  There's a certain self personification projected onto an instrument of one's own building.  I spine crackingly empathized with the literal tension.  A growing crack was forming behind the tuning pins, to the point that each added string increasingly threw all the others out of tune.  I reinforced the wrestplank (doubling its thickness).  So far, it's holding.      

This didn't completely eliminate the downward pluck, but it was better.  Dampers also helped the matter by silencing the ringing of the strings when the keys are released.  For these, cloth capes were rolled, cut, and glued (Duco cement) onto the bottom of sliced single studded 1x2 plates.

The jack rail serves to contain the jacks from flying out of the rack and acts as a buffer which determines key action.  I've set it pretty tight, giving the jacks very little room to move--beyond my preferences, this was purposeful as restricting the leeway presents a more consistent sound.  Hubless tires suspended on axels, one per jack, were hung underneath the rail.

Along with the jack rail, the nameboard is removeable just in case any adjustments are needed.  Due to the odd angles of the bridge and nut, the strings come in from whacky directions, which means each plectrum has a different orientation.  All 61 notes need to be uniquely calibrated.

The lid was tricky in that building it sideways (for smoothness) meant that it crumbled from it's own weight.  Supports were made, but still couldn't keep it together.  So I glued (PVC cement) the supports.  The lid hinges on Technic parts with the case, but the front flaps were made with actual LEGO hinges (

The lid stick is seemingly flimsy, but like the rest of the instrument, is a sturdy combination of large bricks with studs going at opposite directions, packed with plates, fastened with Technic parts, tiled for smoothness, and serves its little function.  Music stand

Reference:
- Kern, Evan J.:

Links:
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