Musical instrument tuner using elastic string

Step 4 Step 3 assembly and tune it

My pencil box was 4 x 8 x 1 in. deep. The strings were 4.5 inches long inside but started with 7 in. long to easily tie a knot and stretch to tune to the C note.
I tied a knot at the closed cup hook rotated the string about3 times clock-wise around the collar and routed it down to the 1/16 hole and clamped it with my hemostat plier close to the hole.Then I strung a crimp bead of 1.3mm ID and crushed the bead with pliers close to the hole.This works better than tying a large knot that wont squeeze through the hole.
I pulled the string and plucked it to get it to sound slightly lower note than the C note I played on my Casio.Then I applied the crimp. Then I final tuned it to C with the tuner screw about 3 rotations or less.

Tune - Each string was separately tuned C lowest Octave, Middle C then High C..Use your thumbnail Start with note D then E, etc Pencil mark each note location where your thumb is holding the string down on the card board plate.The marked 7 notes per string should be located similarly across from each other.
After initial tuning let the finished tuner sit for 2 hours to stabilize then final tune only the 3 strings.
I made this one 3 years ago and had to re-tune it only once a month due to humidity, etc.
Standards rubber bands only were stable for a week.They also broke.
Anyone who knows music can even play a song on this device _{Have fun. Mistic}