Whippen Assembly

The Whippen Assembly - where do they come up with these names?!?  Actually, the grouping of parts commonly referred to as the 'whippen assembly' is 3 separate groupings: Whippen; Repetition Mechanism; and the Jack & Let-Off Button.  

We'll go over each area of the whippen assembly in the next couple of weeks. Below are pictures of both a wooden and a composite whippen assembly on grand pianos.  You can see they are generally configured the same, with design differences specific to the manufacturer:

Traditional Wooden Whippen Assembly

Composite Whippen Assembly

You can readily see the whippen assembly is located directly underneath the hammer shank, and over the top of the key stick.  The whippen assembly transmits the motion of the key to the hammer, which in turn strikes the string to produce the musical sound.

The whippen, is the lower half of the assembly and is in direct contact with the key.  

• 1. Heel
• 2. Heel Cushion
• 3. Body
• 4. Flange
• 5. Flange Rail 
• 6. Hammer Shank Rest Post
• 7. Rest Cushion
• 8. Jack Flange
• 9. Spoon

Specifically, it works like this:  the Heel (1) rests on the capstan screw which is attached to the key.  When the key is depressed, the whippen is set into motion by the capstan screw pushing upward on the Heel Cushion (2) causing the Whippen Body (3) to move.  The body rotates on the Flange (4) which is supported by and attached to the Flange Rail (5).  The Hammer Shank Rest (6) is located at the back of the whippen directly under the hammer shank and topped with the Rest Cushion (7), a felt cushion on which the hammer shank rests when not in motion.  The Jack Flange (8) is built into the opposite end of the whippen to position the jack and allow it to rotate.  The Spoon (9) supports the jack in the proper position.

Next week we'll see how the remaining two parts of the Whippen Assembly contribute to the overall movement.

"The Disclaimer" - Technical Tuesdays are intended to give folks who are curious about pianos a bit more understanding of all those technical terms thrown about by piano technicians.  This is not intended for super-in-depth technical analysis, nor micro measurements; just general knowledge for those who are interested in how a piano works.

Hammer Shanks

The last piece of our hammer assembly is the 'shank'.  This is a long & slender shaped action piece.  Hammer shanks are produced in various sizes and shapes depending on the manufacture and model of piano.  All are generally cylindrical in shape.

On one end the hammer head is mounted (this strikes the string to produce the sound), and on the opposite end, the shank is attached to the flange (holds the hammer/shank assembly in position to precisely strike the string).

Grand Piano - Wooden Hammer Shank

Traditionally made of wood, hammer shanks are now also produced in a composite material that includes carbon fiber, creating a hammer shank that is strong and consistent in strength without being effected by humidity and climate changes.

Grand Piano - Carbon Fiber Composite Hammer Shank

 I love this picture above - don't the hammers look like little faces?  I like to call this one the "3 Stooges".  :)

Vertical Piano
Wooden Hammer Shank

We'll talk more about composite action parts as we move through the piano's action.


Next week - Whippen Assembly!


"The Disclaimer" - Technical Tuesdays are intended to give folks who are curious about pianos a bit more understanding of all those technical terms thrown about by piano technicians.  This is not intended for super in-depth technical analysis, nor micro measurements; just general knowledge for those who are interested in how a piano works.

Body Parts On A Piano?

It's Technical Tuesday & we're back after a short hiatus!  Today we'll be talking about 'Knuckles' and 'Butts'.  Body parts, you say?!?  Let's explore this a bit.

The same component in both a grand piano action and a vertical piano action has two different names.  On a grand piano it's the 'Knuckle'; on a vertical piano it's the 'Butt'.  

This small component is located at the lower (larger) end of the hammer shank, and rests atop the jack which controls the velocity of the  movement of the hammer from its resting point to the point where it strikes the string.  The velocity of this movement is determined by the speed and pressure applied to the piano keys by the player.

The Knuckle

On a grand piano the knuckle is attached to the underside of the hammer shank near the hammer flange.  The knuckle is small and round in shape, traditionally covered in buckskin.

The Butt

On a vertical piano, the butt is located directly on the end of the hammer shank.  A modified square/rectangular shape, the butt is also configured to rest on top of the jack.  Just like the comparable knuckle on the grand piano, this is also traditionally covered in buckskin.

Note: Pictures in this posting were taken of piano action models to allow for close-up, detailed views; and were taken of both traditional wood actions, as well as composite actions.

Next time, we'll take a look a the hammer shanks.  

"The Disclaimer" - Technical Tuesdays are intended to give folks who are curious about pianos a bit more understanding of all those technical terms thrown about by piano technicians.  This is not intended for super in-depth technical analysis, nor micro measurements; just general knowledge for those who are interested in how a piano works.