Another procedure that requires work by hand - watching this will give you a better idea of what voicing a piano is about, whether it's a Bechstein, Steinway, Yamaha or any other piano.
Here's the most intricate process of piano technology - the regulation of the action. Note the weights used to "measure" how much pressure is used to depress the key, the adjustments made to reduce or increase resistance of the key, the flame used to bend the hammer shank so the hammer hits the strings properly. This is a very good "overview" of a job that can take up to two to six days to complete!
They don't leave out any details here - while this is more promotional than informational, it's short, and interesting to note that the piano is upside down when the pedals are installed.
Keyboards are customized to fit each and every individual piano - in other words, you can't take the action out of one piano and drop it in another. Notice that it is all fitted by hand!
Great video of how bass strings (copper wound) are made, and you can see a fellow "installing" the strings, all by hand. You might like the little blurb about the finish that's mentioned, as Bechstein pianos are still laquer finished, not polyester.
It is interesting to note the piano plate is one of the parts requiring a lot of work that must be done by hand.
Note when the CEO walks into the finishing room, he has no mask on - while the sprayers do. You'll notice the overspray drifts toward the wall, to go through the exhaust system. One of the reasons that pianos have become expensive is the means of ecological emissions that the companies use. You'll see Bechstein uses a 3 filter system for the exhaust system.
Still using the sand casting technique to make piano plates, Bechstein marries industrial technology with hand crafting to build their instrument...
The heart of the piano - note how the huge "press" used to glue the board into the piano! I can tell you I don't have one of those in the the garage!
Notice the precision used at this point of building a Bechstein - that's probably why these pianos have been around 160 years!