Upright Piano Action Components & Functions

Question 1

Action: Hammer

Answer 1

A felt covered mallet that has a wood core. The hammer is the part of the action that actually hits the string.

Question 2

Action: Damper

Answer 2

Stops the string from vibrating, thus silences the note after it’s struck.

Question 3

Action: Hammer Shank

Answer 3

A dowel attached to the HAMMER on one end and the BUTT on the other. The shank is usually made of maple.

Question 4

Action: Hammer Butt

Answer 4

Holds the SHANK and the CATCHER. The butt is moved forward by the JACK during play.

Question 5

Action: Catcher

Answer 5

Helps the BACK-CHECK engage the rest of the action and stop the HAMMER from rebounding all the way after the key is struck.

Question 6

Action: Back Check

Answer 6

Catches the actual CATCHER to stop the HAMMER from rebounding too far, thus enabling the JACK to reset itself under the BUTT.

Question 7

Action: Jack

Answer 7

Moves the BUTT forward, thus allowing the HAMMER to hit the string.

Question 8

Action: Let-Off Button

Answer 8

Makes contact with the portion of the JACK called the “toe,” which allows the JACK to escape from the BUTT. This adjustment is called “let off.”

Question 9

Action: Jack Spring

Answer 9

Small metal spring that puts pressure on the JACK and helps the JACK stay in forward position

Question 10

Action: Damper Spoon

Answer 10

The upward movement of the key being pushed causes the damper spoon to lift the DAMPER off the string, allowing it to ring until the key is released.

Question 11

Action: Wippen

Answer 11

The whole assembly that contains the parts responsible for repetition (the JACK, the JACK SPRING, and the BACK CHECK)

Question 12

Action: Capstan

Answer 12

Is located at the back of the key, and it’s purpose is to regulate the height of the JACK underneath the HAMMER BUTT and is adjusted to regulate lost motion.

Question 13

Action: Sticker

Answer 13

The sticker’s function is to hold the CAPSTAN

Question 14

Action: Key

Answer 14

The player presses the KEY to activate the action mechanism. When the player releases the KEY, it and all the action parts reset to the rest position.

Question 15

Belly: Soundboard

Answer 15

Acts as wooden microphone/amplifier, vibrating when strings are struck & increasing volume. Typically made of spruce. Usually 10mm or 3/8” thick. Generally the older & tighter-grained, & more seasoned the spruce is, the better the quality & richer the tone.

Question 16

Belly: Ribs

Answer 16

Diagonal, attached to back of SOUNDBOARD. Usually made of sugar pine. Gives strength to soundboard so it doesn’t change shape over time; they’re glued to it at right angles against the grain of the wood on the soundboard.

Question 17

Belly: frame/skeleton

Answer 17

Holds the belly in place; structural support for entire piano. Reinforced with large wooden braces or posts. On a grand, it’s called a SKELETON.

Question 18

Belly: crown

Answer 18

The convex shape of SOUNDBOARD. Counteracts the tension/pressure of the strings to keep soundboard from collapsing, by keeping compression on it. (Also increases volume & depth of piano). Unstrung, generally 1/8”-1/4” in center of soundboard. Less when strung, but still convex.

Question 19

Belly: Bridges

Answer 19

Attach the strings to the SOUNDBOARD. Vary in length & thickness - treble is long, bass is short. (I think this makes sense when there’s 3 strings in treble vs 1-2 in bass?). Usually made of hard maple or beech wood.

Question 20

Belly: Pinblock

Answer 20

Multi-layered piece of wood that tuning pins are driven into. Made of laminated hardwood, typically maple. Reason for layers is to significantly strengthen the resistance, so that it actually holds the pins with all the tension in place.

Question 21

Belly: Plate / Harp

Answer 21

fits over the pinblock & soundboard; is all you see when looking at the pins. Made of cast iron (usually covered in gold leaf). Average of 18 TONS (36,000lbs!!) of pressure from strings, so NEEDS to be this solid to keep everything from crumpling like a paper cup. Weighs several hundred pounds.

Question 21

Belly: Tuning Pin

Answer 21

Made of Steel. What the string connects in to - comes out of & goes back into for treble (After wrapping around hitch pin). For bass, only comes out of (attaches to hitch pin). Average of 160lbs of pressure on each pin / string

Question 22

Belly: Hitch Pin

Answer 22

What string wraps around after it has gone over the sound board (and before returning to the tuning pin) in the case of the treble. In the case of the bass, it’s what the string attaches to.

Question 23

Belly: Key Bed

Question 24

What are piano strings usually made of?

Answer 24

steel (tempered, high-carbon), and then in the base a steel core wound 1 or twice with copper