Posts tagged flange

Cause & Effect: Piano Key Click

Alright listen up… literally.  Listen for clicks when you play each note on your piano.  The cause? Well… kinda like the last post of Cause & Effect, there are many many things in a piano that could make noise but the most common – 2 things: Loose flange screws and loose flange pins. 

Ok calm down… i know you don’t know what a flange is so i’ve conveniently uploaded a pic for you.  Shown here are the hammer, shank and flange.  The flange is the jointed piece at the bottom that is attached to the hammer rail.  When the hammer strikes the string, believe it or not, the force will go running down the shank and into the flange.  If the flange screw is loose, you’ll hear a click.  After you tighten the flange screw, if it still makes noise, dollars to donuts it’s the flange pin itself.  The flange pin is a small little steel pin.  When it gets worn out and the joint is too loose, it’ll manifest that looseness by clicking.  There you have it! The most common source of ‘clicks’ in pianos.  And like the other post on Cause & Effect… better to ask the technician to remedy the situation.

Cause & Effect: Piano Key Sticking

This post speaks to the problem of sticking piano keys.  There are usually about 6 spots to check on any piano if a note is not returning to normal playing position.  But before we get into the mechanical, think of the obvious… is it getting blocked? I mean… believe me when i say i’ve seen LOTS of things inside pianos.  Here’s my list thus far: pencils & pens, toys, hair pins and bands, sheet music, tools, rubber bands, paper clips, coins of various sizes, ladies press on nails (ewww… that kinda creeped me out finding that one… especially since i got the piano from a home where she had died), believe it or not metronomes and decorative piano blankets.  Hmmm have i missed anything? So make sure it’s not getting blocked.

Once you’ve determined that it’s not blocked or broken, however, there’s a REAAAALLY good chance friction is to blame.  Usually the hammer FLANGE is the culprit – it’s the joint connected to the hammer.  About 80% of the time there’s wayyy too much friction on that joint and the centre pins need replacing.  Two other joints – the action flange (flange is just another word for joint BTW) and the whippen (repetition lever) also have jointed parts.  Any time you introduce a joint, you also have potential for problems.  So that makes up 3 of the problem areas.  Then the key stick has two bushings – each of which could also have too much friction.  And finally, the key slip – the rail in front of the key sometimes catches on the front of the key.  Invariably it’s one of the 6 parts.  How do you go about fixing it? Hahaaaa… i didn’t mention i would give the solution… only the cause of the problem.  MOST problems can’t be fixed without a technician.  Sure you can look down inside and see if there’s something obvious but if it’s not… you need to get an expert in to address the problem.

The Broadwood Piano – remaking the silk purse

Recently i was hired to work on a Broadwood grand.  Now for those of you who don’t know, Broadwood has an illustrious place in the world of piano making.  Established (get this) in 1728 (yes you read correctly), this company made pianos for royalty (obtaining the Royal Warrant for manufacturing – see lower left photo) and had probably the most famous historical endorser Beethoven himself.  Upon gifting a grand piano from Broadwood, Beethoven wrote a thankyou letter back in February 1818: ” I shall regard it was an altar upon which I will place the choicest offerings of my mind to the Divine Apollo”.  Think about the fact that this company was established 125 YEARS before Steinway.  Now obviously in the early days they were manufacturing clavichords, harpsichords and square grand pianos.  The Broadwood company became known for their actions (internal mechanisms) and also is credited with the sustain pedal.

The piano i had the opportunity to work on was a “barless” grand meaning that it had no reinforcement bars or ‘struts’ to hold the tension of the almost 18 tonnes of string tension.  Instead, Broadwood made a full perimeter frame which appears to be almost double in thickness – making this an extremely heavy instrument.  (see photo of strings) The major problem with the piano i worked on was that it had a cracked action rail.  If you’ve ever seen the inside of a grand piano, you’ll know that all of the hammers are screwed in place to one long rail called the action rail.  If the action rail is cracked, many things happen – first, you don’t have a solid base to attach the hammers.  That creates ‘travel’ where the hammers will jostle about not hitting squarely the strings.  Second, believe it or not, if a screw is so much as even loose on an action rail, you’ll hear the subsequent ‘click’ of the hammer.  So there were a number of hammers clicking before i attended to it.  And finally, the regulation. Regulation is the process of fine adjustments to streamline the flow from key to hammer.  It’s what makes a piano feel ‘right’ or positive.  With a cracked action rail, the hammers wouldn’t stay in alignment.  After quoting on this job, it then struck me… “what have i got myself into?”  Action rails have nearly 200 screw holes, thickness requirements down to the thousandths and fore and aft placements that need tending to.  Well i’m always up for a challenge.  And so before ripping this piano apart, i went back to the calculations.  There’s a joint near the hammer called the flange.  And for those who are interested, mathematically, you should be able to compute flange height.  Simply, the string height inside the body of the piano minus the length of bore (LOB) – which is the centre of the shank to the tip of the hammer SHOULD equal the bird’s eye.  The what? The bird’s eye is the nickname given to the joint of the flange.  See? It looks like an eye… kinda… ok maybe not… but it’s a steel pin surrounded by cloth inserted into wood.  So after calculating the bird’s eye, i managed to then thickness sand the new rail just under 3 thousandths of an inch (about the thickness of a piece of paper).  So once everything was installed? The moment i had been waiting for… it WORKED! but it just needed a lot of adjustments refitting the old parts.  It was a fun experience and more than that, exciting to bring a tired Broadwood (the silk purse) back to life.

The Black Hole of Pianos

Every piano has one… a black hole.  It’s the place where all the pencils disappear to.  Paperclips magically are sucked into it… Heaven forbid anyone should be doing their theory homework at the piano and an eraser falls inside.  And once inside the abyss… gone forever!  HAhaa… at least that’s what i used to think when articles would fall inside the piano when i was a kid.  And on pain of death we were threatened to never go tinkering around the inside of the piano (which is still probably good advice for kids and pianos…lol).  So when the piano tuner would come, he would unravel the mysteries of the universe… “Well… looks like that click sound is actually coming from a pen that fell inside.  Oh and here’s another pencil.”  I remember seeing the inside mechanism of a piano for the first time in my early teens.  (Formally called the “action”).  When i witnessed the hammers and levers i remember having this brainwave. “Sir? Can you make the keyboard on my piano heavier?”  We had an old upright piano and with 4 kids – 3 of which ended up with diplomas in piano, you can imagine the beating it endured.  But when i went to my teacher’s place where there was this beautiful modern 7′ Yamaha grand piano, i noticed how vastly different the touch was.  And so the answer from the tuner? Simply “No”.  No explanation. End of Story.  I thought to myself, in all this gobbledeegook of levers maybe there was some adjustment that could be made to give me a grand touch.  I was young and naive and this technician had no time to explain and so i was left with no alternative than to think that it’s impossible.

For the most part, however….unfortunately he was right.  I’ve had MANY people ask me to transform their piano into a firmer touch but to understand piano touch more, i’d like you to think of your piano like a scale.  On one side is the key of the piano – the black and white notes.  On the other side remain the hammers and the action.  So most pianos have about 55-60 grams of touch on each key.  What that means is:

                         Finger Pressure (55grams) = Hammers + Friction

Most of the weight of a piano is in the physical motion of the hammer itself.  Now if you know anything about hammers, put one on a scale and you’ll find out that it weighs about 8 grams.  Attach it to a piano action and all of a sudden, there is a 5:1 ratio of hammer weight.  What that means is that the lever system in the piano multiplies the hammer weight by 5.  An 8 gram hammer then will feel like 40 grams at the keyboard.  Add 15ish grams of friction and VOILA! Piano touch.  A 9 gram hammer (times 5=45) plus 15 grams of friction forms a touch of 60 grams at the keyboard.  ONE gram on the hammer makes a 5 gram difference at the keyboard.  When you think that a nickel weighs 5 grams, adding one-fifth of that is not a whole lot of weight and yet you’ll EASILY feel the difference installed into a piano due to the ratio.  Make sense?  Is it not possible then to simply add friction to the piano? Adding friction is not the answer.  Friction is a careful balance.  Too little and the piano feels too ‘loose’ and results in noise. Too much friction and the piano has sticking parts and feels sluggish.  If your piano is old however, you may have worn out “joints” or pivot points.  There are 2 areas which can be monitored which make any piano feel more “positive”.  One is key bushings (see the article entitled “Aye There’s the Rub) and the other is called the hammer flange.  (A flange is just a fancy word for hinged part on a piano).  The hammer flange… if you follow your eye down the stick (called the shank), you will see that it is jointed at the base.  New flanges (albeit costly) and key bushings are the biggest culprits for too much/too little friction.  And so without opening pandora’s box more… my original question to the tuner:  Can’t you change simply change the touch on the piano?  Operative word in that sentence is “simply”.  It can be done.  It’s just not simple.

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