Picture of MINI-PIANO
    This Instructable illustrates the steps in making a stringed instrument to which piano keys are added and played like a piano over 2 octaves. This Instructable  is based on my earlier Instructable on making a mini-zither {posted Aug.5, 2009. but adds keys.

Step 1: MATERIALS-Preliminary instructions

Picture of MATERIALS-Preliminary  instructions
aKMiniPiano9-30-09 007.jpg
This step will describe the device . I initially made a stringed instrument  I called a zither in my earlier Instructable titled "how to make a mini-zither of 2 octaves" Please refer to it for basics of using elastic poly-string materials and tuning. However, I included another resonating box construction that is of a smaller dimension for this piano project. After making the assembly, stringing, tuning, etc. the final step is to add piano-like keys which I have outlined in my Lab-Book pages here for ease of assembly.
   A little input here is required. A true piano has keys that strike the wire strings. I have deviated from this mechanism by inventing a different method of sounding the string note. It entails a novel method of grabbing the string with an adhesive pad that then pulls the string up , releases it to sound a note.The adhesive I have chosen is Uglu (r) by Mactac {www.ugluit.com} .Packages for  a dollar  are available from craft stores.
Packages  contain enough adhesive strips for several instruments. Other adhesive tapes (two-sided) can be used as Scotch[R] mounting adhesive or Foam- tapes  for mounting pictures on a wall.
      Lifting arm- Use coffee-stirring sticks of wood.See details in note book.
      Tubing - again I found stir sticks of plastic would work that a coat-hanger wire would feed in-to. Wire is used as an axle for the keys to rotate on.
       Gluing the wood sticks to the tubes is done with paste type adhesives as two part epoxy. {Eclectic Products  Super-mend epoxy.}
       Keys- Use vertically mounted wood sticks  glue to end.
       Weights- used for application of downward force to the glue tipped wood sticks onto the strings.I found Plumbers solder to be easily formed to correct weight. I experimented with wire springs  and found them hard to set correct down pressure.
       Overall covering- any plastic and cardboard to locate the keys  as in a piano.
bugman1133 years ago
The idea is fairly cool and creative, my only complaint is that this is technically not a piano, it's closer to a harpsichord in the sense that it plucks the strings as opposed to striking them which isn't a bad thing just factual. I'm hoping I can find the time to make this
mistic (author)  bugman1133 years ago
Hi0;; I agree. others have made similar observations and I will be sure to call it the harpsichord project.
I have made another "piano" oops Harpsichord " too later. see Inst'bl.
It included the half notes [ # b] keys. Still sounds good after 3 years use.
Whales4 years ago
I am glad i have found this, your lap piano instructable is good, but something about it irks me, no offence to you, i just can't place it. I plan to possibly look through this and see if i can alter it back to strike the keys instead of "plucking" them. I've always loved homemade instruments, and a homemade piano couldn't make me happier.
mistic (author)  Whales4 years ago
sorry I could not answer sooner. Striking the string with a hammer is something i have tried .It wont make a sufficiently loud sound unless an amplifier mike combo is used. It is possible though. The key to hammer mechanical concept is possible but complicated and i gave up on that. Then i just went back to plucking using the adhesive tips and simple levers.
let me know if you have any leverage ideas to strike.
I experimented with reverse of the pluck from string by having the lever suspended above the string and the key would push tthe adhesive tip down onto the string and then pull up and release to cause the string to vibrate.How ever i could not mute the string vibration when i want a quarter note.
Whales mistic4 years ago
hm well as for the loud sound part, i think you would need a bigger/thicker/better(take your pic) sound board, the small thing is cool. Definitely works, and i know you want the thing small, but for a louder/richer sound, you'll need a nice sized sound board.

I have been studying upright mechanisms for a few weeks(on and off) and have come up with a design or two, but i have to get the materials to make it before i can test it. If you know a program that could do that, it would be very appreciated.
thepelton5 years ago
I take it this instrument has no sharp or flat notes in its present incarnation?
mistic (author)  thepelton5 years ago
they can be played using the finger pressure on the string at the top.
Press 1/2 inch down from top on Cnote.. strum it- presto you hear a C# note.
I like it... Half guitar, half harpsichord. Guitarpschord?
LkArio5 years ago
Does this work by plucking or hitting the strings, with a tangent that remains in contact or a hammer that goes back in place?
Does it have dynamics?
mistic (author)  LkArio5 years ago
hi- the finger  rests on the string until plucked.The return is automatic when the keys are released.
omnibot5 years ago
That is nice! Could've been more datailed though.
mistic (author)  omnibot5 years ago
Hi O- I was hoping that the Notebook pictures would give the details in depth . I may have to generate these plans using Paint or other software.
I will let u know.and I will add to the Inst.
omnibot mistic5 years ago
That would be great, it's a fun project.
mistic (author)  omnibot5 years ago
I have made additional refinements to the keys but I have not edited the figure yet.
Basically, I added steel pin dividers between the keys to allign them more easily on the strings. Also am learning to draw blueprints using Paint.Net.
dan2805 years ago
you should change it to mini-harpsichord as it should be plucked
mistic (author)  dan2805 years ago
Harpsichord  it will be  ,too.
mistic (author)  dan2805 years ago
thanks, we will definitely  tell people it sounds like a harpsichord  too..
mistic (author) 5 years ago
A friend  sent me a note that this instrument  sounds like a clavichord since the strings are plucked. Interesting observation.
I give an A+ for sound quality and creativity, but a C for aesthetic value
mistic (author)  MechEngineerMike5 years ago
I have actually made  some mini-zithers and lyres that are strictly string instruments that are played with the fingers or strummed with a pick. I have pictures of these if any one is interested. .
This is a one-day-project, it is highly successful. 

Aesthetic details cost much, and in my opinion are secondary in this case.
mistic (author)  MechEngineerMike5 years ago
Thanks MEM- I had  to figure out something  here as I wanted to enter this in a contest. I will try to be aesthetic - Maybe a varnished wood top cover and nice keys...
rimar20005 years ago
Very nice instrument. But I don't understand the hammer's mechanism. Maybe it is in the video, I can't view it at work.
mistic (author)  rimar20005 years ago
Hi R2000- In pianos  they use a felt hammer- I replace it witha adhesive 'grabber' that grabs the string- the key stroke pulls the adhesive stick up and releases it to vibrate the string. The PullUP distance is about 1/4 inch. The lever mechanism  i came up with is tossed together using swizle sticks. soda straws for tubing and  coat-hanger wire for the main axle.  I suppose a compression spring under each lever   would be the mechanic's method of replacing my solder weight method to return the tip back to the string after the stroke completion.
I I could see and hear the video at home, the little piano is well-tuned. Very clever the idea of the adhesive tape.
mistic (author)  rimar20005 years ago
Yes rimar- I tried  various mechanical ways to pluck the strings using a pick, a needle. rotating  2-tip propellors, etc. and only the adhesive worked properly.
I do not know about the effects of time on the adhesion properties of the mounting tape adhesives but they are used for years to hold up pictures,coat hooks, etc. and dont lose their adhesion .
    All my projects are essentially prototypes  aesthetics comes later.