Showing posts with label regulation. Show all posts
Showing posts with label regulation. Show all posts

Wednesday 27 October 2021

The Perfect Touch

The hunt to find the piano with a perfect touch would be a very tough assignment. On a 10 point checklist of qualities required for consideration, very few pianos would achieve 10 out of 10.

Though wonderful specimens of the piano maker's art, even expensive new pianos, are often short on the magic that sparkles when the action and keys supply the player with the wings of creative inspiration - allowing flight to that mysterious zone where, the player is released from the confines of unsatisfactory playability, and enjoys the timeless pleasure of music making purity. This zone is home to the perfect touch. Playability fulfilled!

A tuner/technician's experience will agree that perfection in a piano is almost unheard of! My old boss, when I was an apprentice, often used to say, "Pianos are imperfect instruments!" - of course, back in the 1970s, he was right - the pianos of the time were generally very poor and always, had issues. I think he got tired of having to find new things to say to customers who rightly felt disappointed with their purchases.

Surely today, pianos must be somewhat closer to the ideals of the piano designer's blueprint! Throwing money at the problem is not always a complete solution - indeed, unless the those undertaking the challenge of sorting it out, know exactly what they are doing, the finished piano might still only be an expensive disappointment.

We, in the trade must strive for excellence and then, go the extra mile, make an art of the job, sprinkle with gold dust and unlock the wonders of a well regulated action and give the 'Perfect Touch' within, the chance to inspire further generations of keen pianists! 
   

Wednesday 5 November 2014

Regulating a Bluthner Action in a Bluthner Grand

Up until about 1918 Bluthner used their own Patent Action in their pianos. For a grand piano, this action was strikingly different from the more standard ‘Roller’ action. Regulating these actions cannot be done by trying to apply the procedure used for the roller action. 
These instructions are based on a leaflet produced as a guide to regulating these pianos. Some familiarity with these actions is absolutely necessary before attempting this work.

The necessary operations must be carried out strictly in the following order. The fitting of the Bluthner Action is based on a tough depth of 9 mm and a hammer-blow of 45 mm.

1. The hammer heads should be spaced exactly to the strings and the hammer-flange screws should be tightened.

2. Setting-up. The guide-pin of the abstract must be straight and vertical. The jack must be so adjusted - by means of the carriage which is screwed on to the key, that it drops quite easily under the nose of the abstract.

3.Set-off. The hammers should release 1.5 mm from the steel strings and half a string thickness from the bass strings - the set-off screws are situated on the hammer-rest rail.

4. Touch. Contrary to the Erard Action, the touch is made quite firm. The key is depressed slowly on to the touch-baize, after which the hammer should continue to rise 1 mm up to the set-off point. Only on striking the key strongly will the hammer be caught by the back check. (No after-touch).


Bluthner Patent Action
5. The checks must be cranked and spaced equally. The checks must each be parallel and central to the hammer woodwork. Now the hammers are checked. There is no special height but it should be about 24 mm above the hammer line. 

6. Drop. The guide pin of the abstract must move easily in the bridge leathers so that the abstract drops of its own weight. The repetition springs must move freely in the abstract felt clips and by pressure of either side of the right-angle spring, the drop is controlled. The hammerhead should drop down 3 mm after setting-off.

7. It is now necessary again to check the touch throughout.


The abstract
8. The dampers should lift when the keys are half depressed.

9. The damper shade-rail has to be adjusted so that when pressing down the sharps, there is very little play.

10. The coiled spring which is attached to the abstract should, in the normal position of the key, not rest on the jack, but remain about 3 mm from it. An even touch is of the greatest importance.

Technical File

©
Pianology

Friday 24 October 2014

Regulation of a Grand Piano Part 2.

2. The 'lost motion' between the moving of the key and the hammer's beginning to move should be adjusted out using the pilot screw beneath the felt pad of the whippen foot. When at rest, the hammer shank should be about 2 mm above the hammer rest felt and the nose of the hammerhead is 47 mm from the strings. Some compromise will be required here, though, if both measurements cannot be achieved, favour the 47 mm hammer blow - try to get as close to this as possible.  



3. With the action in the piano, set the let-off point of a few sample keys to about 3 mm from the strings. The let-off point is the point at which, after the set-off, the hammer comes to rest on the repetition lever. (Often the set-off is so low that the let-off cannot be set. If this is the case, raise the set-off high enough to allow the let-off to come into play). I set sample keys every 5 notes - a major third and the notes in between. Holding 2 sample keys down, line up the let-off points for the 3 in-between notes.


4.Next job the set-off - this can be done on the work bench. The Set-Off is the point at which, when slowly depressing the key the hammer falls away from the string. This is the famous escapement taking place. Holding a key down (the hammer resting at the let-off point) set the neighbouring hammer's set-off point to about 1 mm above the let-off point. repeat across the keyboard.   

5. Regulating the check-off. This is where you simply play a note and hold the key down - the hammer comes to rest (having been caught by the back-check). The distance from the string cannot be fixed as a general rule. The crucial point is that the repetion lever is 'charged' and ready lift the hammer when the key - and therefore the back-check - is released. To achieve this the check-off point must be lower than the let-off point.

6. Regulating the repletion springs. When the key is held down after striking the string, the hammerhead is held by the back check. When the key is released slowly, the hammer should gently lift up to 6 or 7 mm. When the spring is too weak, the hammer falls away from the strings. Too strong and the hammer kicks up. The spring should be adjusted so that the hammer lifts gently. Sometimes the springs have to be bent in order to strengthen of weaken them, but sometimes there is a simple screw adjustment. This adjustment has to be made for all 88 notes! 
7. Regulating the dampers. This is perhaps the most demanding of stages in the regulation process. Some pianos have easy adjustment features but mostly, you have to set each damper to begin lifting from the string when the hammer is about half way up to the string. At the same time every damper should lift together when the pedal is operated. This is a trial and error issue and you keep going until you get it right.

Back to PART 1

© Steve Burden

Regulation of a Grand Piano Part 1.

Regulating a grand piano is not as simple as just taking accurate measurements and making slight adjustments. Many years ago I telephoned an Action Manufacturer to order some action parts and during the conversation I asked if there was a 'regulating manual' for their actions. I thought there must be some written instructions but the response was an emphatic: "No!" 

So we in the piano trade are left to make as much sense of regulating a piano as we can! Experience is important but having a keen sense of what works well and being dissatisfied with ignoring obvious problems is crucial if we wish to find success. There are good books which will explain what happen during the stroke of the key but not even these will help when correcting some of the many possible problems. Regulating work, even on new pianos, is not as simple as we might hope. 

Fortunately, there are principles which, when understood, form a structured approach to get the job done. The following is my own method for regulating - it is not the only way, but I have found it to work well on most pianos.

Please note: while regulating pianos, some improvisation is required to get the best out of any given piano.

Most actions work well if the depth of touch is 10.5 mm. and the hammer blow 47mm. 

1. First job is to level the keys and set the depth of touch - best done with the upper part of the action separated from the keyboard. With a set of lead key weights, place the weights on the front end of the white keys (front of the ivory key tops so the the keys are resting on the front-touch baises) and level the keys so that across the keyboard they appear perfectly in line. Any adjustments are made using paper or card washers under the front-touch-baise.

Then, for a few sample keys, attach the weights to the back check and measure the depth of touch at the front of the key (as compared to the keys with the weights still sitting on the front - I set sample keys every 5 or so white keys). Touch depth should be 10.5 mm.

This done, gradually transfer the weights to the back checks and level each of the white keys to be in line with the sample keys. This takes care of the white keys.

For the sharps: with the lead weights still clipped to the back checks, ensure that the top surface of the sharps, when resting on their individual front-touch biases are about 1 mm above the top surface of the white keys. Again, set a few sample sharp-keys ensure sharps are level and then proceed across the keyboard. 

Then, with a few sample sharps, attach weights to their back checks and set the height of the front end of the sharps to be 12 mm above the top surface of the white keys (These white keys must also still have the weights on the back end of the key). Using sample keys as a guide, continue to level all the sharp keys across the keyboard.

The upper part of the action is now screwed back onto the keyframe.

©
Pianology