The Rube-Goldberg Machine Lurking Inside Your Piano

What the Heck is a Rube-Goldberg Machine?

You’ve most likely seen a Rube-Goldberg Machine even if you never knew what it was called. A Rube-Goldberg Machine is named after Reuben Goldberg, an American cartoonist, inventor, and engineer who rose to fame with his satirical cartoons depicting complex machines performing simple tasks. (Do yourself a favor and perform a Google image search for Rube Goldberg cartoons. Look for Self-Watering Plant, Automatic Sheet Music Turner, and Professor Butts and the Self-Operating Napkin, among many others. They’re a hoot!)

So, You’re Saying There’s a Cartoonist Inside My Piano?

If there were a 142-year-old cartoonist inside your piano, you’d definitely have discovered him by now. What we’re saying is that your piano is very similar to a Rube-Goldberg Machine.

Now at first glance, your piano seems like a super simple instrument. You press a key, a hammer inside the piano hits a string, and BOOM…instant sound, right?

Not really.

There are dozens of pieces that create the action mechanism that allows what appears to be a very simple cause (press a key) and effect (notes emerge) when playing your piano. Think of it a little like that old song we all learned as kids: The foot bones connected to the leg bone and the leg bones connected to the thigh bone. Etcetera, etcetera.

Similarly, your piano is a complex assembly of wood, felt, wires, hide, and glue housed within a wooden cabinet on a cast iron frame. It’s a Rube-Goldberg Machine that actually works!

Remember that old board game, Mouse Trap? Or maybe you’ve seen that super complex music video of This Too Shall Pass by the band OK GO? Your piano is like those…a series of individual pieces that create a cascade of individual actions that start at your fingertips and end with one to three strings vibrating in unison.

To make things even more complicated, there’s a difference in how those actions work inside an Upright piano versus a Grand piano.

The Chain of Action in An Upright Piano

The Upright is possibly the more straightforward of the two instruments.

1. Pushing the front of the key down lifts the back of the key up.
2. The back of the key twists the Whippen (located between the key and the hammer, connecting these parts in the piano’s action mechanism).
3. The back of the Whippen lowers, engaging the Damper and lifting it away from the string.
4. The front of the Whippen lifts, pushing the Jack against the Hammer Butt which pushes the Hammer towards the String(s).
5. At a certain point the Let-Off Button releases the Jack from the Hammer Butt allowing the Hammer to travel the rest of the distance under its own momentum to strike the String(s).
6. The Hammer rebounds from the String(s) and is caught with the Backcheck which is attached to the front of the Whippen.

Upon releasing the key, the back of the key is lowered to its starting position, which untwists the Whippet allowing the Damper to settle back against the strings and stopping them from vibrating. It also allows the Jack to return under the Hammer Butt, and the Hammer to reset in its rest position.

The Chain of Action in A Grand Piano

The Grand piano has a couple of extra steps beyond what happens when you press a key on an Upright.

1. Pushing the front of the key down lifts the back of the key up.
2. The back of the key lifts the Damper Lever, which pushes the Damper Wire up and lifts the Damper off of the String(s).
3. The back of the key also twists the Whippen which lifts the front of the Whippen up and then pushes the Jack against the Hammer Knuckle and raises the Repetition Lever.
4. The contact of the Jack to the Knuckle pushes the Hammer towards the String(s).
5. At a certain point the Left-Off Button and the Drop Screw contact the Jack Toe and the Repetition Lever to release them from the Hammer Knuckle allowing the Hammer to travel the rest of the distance under its own momentum to strike the String(s).
6. The Hammer rebounds from the Strings(s) and is caught with the Backcheck which is attached to the back of the Key.
7. Upon partial release of the key the Hammer releases from the Backcheck, is caught and held by the Repetition Lever after which the Jack slips under the Hammer Knuckle ready for the key to be played again even though it has not been fully released.

Upon releasing the key completely, all parts return to their starting positions.

A Grand Piano can replay a key that has only been partially released allowing for quick repetition of one note, while the Upright lacks this mechanism due to the differences in the action orientation and design.

Whoa, Oh, Domino!

Similar to setting up a domino chain reaction a piano’s action has its own set of finicky spatial measurements between the parts to allow everything to operate smoothly and efficiently.

When you purchase a new piano, before it leaves the manufacturer it has undergone a setup of the action parts called a regulation.

When a piano is played heavily (such as one played in an orchestra or by a professional performing musician in a band) it will require a technician to reset the specs through a regulation service. It takes longer to perform a regulation service on a Grand piano than on an Upright because Grands possess the previously mentioned extra features. Ultimately, a full regulation service will require several hours, perhaps spread over a couple of days, to complete on either type of piano.

For most people, their piano will never require regulation for a few reasons. First, if it isn’t played heavily over the course of ownership it won’t require one. Second, the piano might not be worth the expenditure of regulation services which can run several hundreds of dollars. Third, it’s not the kind of piano that would merit a regulation. Ultimately that would be determined by a certified technician. For example, some technicians would never regulate a Spinet style piano or any piano with a Dropped Action. Alternatively, there are some pianos that receive regulations every couple of years, like those at a concert hall or in a music conservatory’s fleet.

Not as Simple as You Thought

The complexity of the piano’s inner workings is pretty amazing. (Think of that the next time you think plunking out Three Blind Mice on the keyboard is a simple task.) It’s a very large part of the reason you want to make sure your piano is always in tip top operating condition.

Contact us if you have questions or are in need of piano services. We’re happy to help!