GRAND REGULATION - part V

Section III. Alignments

27) Align hammers to strings

To facilitate this alignment procedure, install the action into the piano and make a rough check of the let-off measurement. If the let-off is very far from the strings, the hammer-to-string alignment will be very hard to make. So try adjusting the let-off by say one-half or one complete turn of the adjusting screw and see what number of turns it takes to get the hammer to let-off right next to the string.

At this point in the regulation procedure, if the hammer blocks on the string, it will be all the easier to make the alignment. Then remove the action and turn all of the let-off screws the number of turns that you found necessary to get the hammer closer to the strings.

Before starting to centre the hammer to the strings, make sure that the hammers have been filed, removing all traces of former string grooves. If the piano has agraffes, then your job will only be to align the hammers to the strings. If the piano does not have string aligning mechanisms throughout, then you must make sure that the strings are properly spaced and centred before attempting to align any hammers.

Normally, unless the plate has been repositioned or a bridge reglued onto the soundboard, there should be a straight line running from the hitch pin through the bridge pins and on to the tuning pin hole in the plate. The middle string of a trichord should run along this line, with the right and left strings having the same inward pointing angle, since the bridge pins are wider spaced than the spacing at the V bar.

Begin aligning the hammers to the strings by taking a wire hook and coming down from the strings, lifting the shank so that the hammer blocks on the string. Or, take a finger and lift the bottom of the whippen taking the hammer past let-off and pushing up until the hammer again blocks on the string. I prefer the latter method since the wire hook is slower and can cause the hammer to be pulled to one side if you are not careful.

Looking directly above the hammer, check to see, if it is properly centred to the strings. For a trichord, equal amounts of hammer should be seen on both sides of the unison. On single or double unisons, the hammer can either be likewise centred, or they can favour the bass side a little, depending upon how you want the hammer to strike when using the una corda pedal.

Any hammers which are properly centred on the strings, I mark with an “O” on the key with a piece of chalk. Those which are off to one side, l mark with a straight line on the key to the side which they need to go, varying the thickness of the chalk mark as the amount the hammer needs to be moved. Do one section at a time.

Pull the action out after chalking all of the keys, and compare the marks with the way the hammers look. All of the chalk marks must coincide with either a perfectly centred hammer or else a hammer that needs to be traveled, angled, spaced, or a combination of these three.

Place a long screwdriver blade or other object such as a spare pedal rod under all of the shanks in this section and check the hammers first for traveling. Even though a key was marked “O” the hammer may be traveling or have the incorrect angle. After correcting the traveling, heat the shanks of those traveled along with any others whose angle needs to be changed until all of the hammer angles look uniform. Lastly, space the hammer by slightly moving the flange sideways.

If the flanges are of the type where a screwdriver or flange spacer can be used, install the action into the piano and space the flanges directly by lifting up the hammer until it blocks on the string. If the flanges are not of this type, then they must be spaced outside of the piano. Use the width of the chalk marks as a guide to how far to move the flange, and try to use any keys marked with the “O” as a point of departure.  

I get two keys about five or six keys apart marked with the “O” and work from these, putting t action back into the piano and making any needed refinements.

Remember that some manufacturers have a two degree tilt hammer on the shank. The more the hammer was bored at an angle to match the angle of the strings, the more likely it is the hammers will have to be tilted on the shank to properly space the hammer to the string and to make sure the tails do not interfere with the adjacent hammers.

Centre all of the hammers in each section in the manner shown. If someone altered the plate sideways, for instance when installing a new pinblock, or if a soundboard was replaced and the bridges are a little off to one side, good luck!

28) Align and square whippens to the knuckle

Ideally, when the shank and flange assembly is made, the bottom of the flange should be perfectly flat and the birds-eye be drilled correctly so that the centre pin is perfectly horizontal. The shank bushings should be perfectly fitted so that the bisects the shank, and of course, the knuckle should be ungrooved and perfectly round, being glued onto the shank squarely. Such an assembly would have no need to be traveled, making the knuckle tilt the one side. Sweet dreams.

What happens when a tilted knuckle receives a strong blow from the jack? If the jack is also at the same tilt, very little power is lost, and rather little wear results. But when the jack is not on the same plane as the knuckle, power is lost and abnormal wear results. Every time the jack hits the knuckle, the power from the key is transmitted by the tip of the jack to the knuckle, not by the whole top surface of the jack. Power is lost here. Worse yet, the jack centre pin and bushing take a beating. Likewise, the knuckles wear at one spot since the corner of the jack inflicts the blow. The shank then is given a twisting motion at the centre pin instead of an even straight blow, again resulting in a loss power and abnormal wear to the shank bushing. The best relationship is when the whippen and thereby the jack is tilted to match the tilt of the knuckle.

Granted, tilting the whippen results in the capstan no longer hitting the whippen felt squarely, and the whippen centre pin and bushing get a little twisting motion. But remember, the capstan is rounded, so the whippen felt is not abnormally worn. Also, keep in mind that the arc of travel for the whippen is far less than the shank, and the whippen centre pin is further from the transmission of power than the hammershank centre. The lesser of evils is definitely to tilt the whippen.

Therefore, when spacing the balanciers to the knuckle, look at two things:

1) Does the tilt of the whippen need to be changed to match the tilt of the jack?

2) Should the whippen be moved sideways to keep the capstan centred under the whippen felt?

If tilting the whippen aligns both the knuckle to the balancier and the whippen felt to the capstan, all is well. But, if tilting the whippen puts the knuckle in line at the balancier and not the capstan at the whippen felt, then compromise. The balancier must always be centred with the knuckle, even if the tilt of the jack does not exactly match that of the knuckle. The capstan can be a little off to the centre of the whip much as to cause the capstan to be on the edge of the whippen felt.

To tilt the whippen, loosen the flange screw and tilt, then retighten the screw. Sometimes the flange must be papered underneath on one side. To space the whippen sideways, remove the flange and paper the flange on the side that you wish the whippen to move. This is the opposite to papering a hammershank flange. For ease in removing the whippen flanges, it is best to remove the hammer rest rail first, if there is one. 

GRAND REGULATION - part IV

II. THE TOP ACTION (off the keyframe) - continued

22) Clean repetition spring and groove (Steinway, Yamaha, Bosendorfer). On Steinway, Yamaha and the Bosendorfer whippens (which have the butterfly type repetition spring), the spring grooves are coated with a graphite solution. The Yamahas now use a teflon coating here, but the older models of this type whippen are graphite.

Hurray that someone has finally seen the light! This graphite paste becomes dirty and gummy, and makes for a source of friction instead of eliminating it. These grooves in the underside of the balancier and the spring tips must be cleaned in order to achieve a good regulated action. If left uncleaned, the jack height is very hard to set since the repetition spring not only has to support the knuckle, but also has to overcome this messy graphite paste as the balancier moves.

To clean this groove, release all 88 repetition springs from the grooves and turn the action upside down, taking care to protect the hammers while doing so. Run a piece of cloth up and down the grooves until clean. Be careful not to damage the groove. Now choose a lubricant  which will, hopefully, eliminate this problem during future use. I have tried three different lubricants for this job, but I have reservations about all three of them. If any of the readers have a sure-fire method to solve this problem, please be kind enough to share it!

I have tried:

1)            Dag 154. This is a graphite solution and works well for lubricating the spring. I question whether it will be free from the dirty, gummy mess which plagued this area in the first place.

2)            Spray teflon. I feel that this teflon is not as good as what is available to the manufacturers. It does not seem to last. Hence, the repetition spring, while not getting dirty and gummy, will also not be lubricated quite well enough.

3)            White grease. This is supposed to prevent rust and corrosion on the spring. It is not absorbed into the wood, but it is bound to get dirty with time. As to whether it will also get gummy and inhibit the spring is anybody’s guess. The ideal would.be to apply a teflon coating like what Yamaha now uses, but to my knowledge this is not available to technicians.

Turn the action right side up and clean the tips of the repetition springs with a suede brush. Rebend the springs back into their grooves, making sure that the spring is indeed in its groove by applying as light sideways motion.

23) Round whippen felt if needed. The cushion felt on the bottom of the whippen which rests upon the capstan always compacts and gets worn from the constant hammering of the capstan hitting against it. Incidentally, this compacting along with the flattening of the knuckle is why a new piano always loses its hammer line. In the case where these parts have only “settled in”, the action can be brought back into regulation by raising the capstans and making the corresponding adjustments in the let-off and drop. Since raising the whippen puts the jack tender closer to the let-off button and the balancier closer to the bottom of the drop screw, these two must be changed.

I use two wear areas, the knuckle and the whippen felt, to decide whether to repair an action or to replace the action parts. Just like a flattened knuckle, a worn whippen cushion felt must be replaced. I find it far less hassle to just replace the whippens and shanks/ flanges instead of taking the time to try to repair these parts. But, if the piano is obsolete or if only a little worn, the whippen felt can be rounded back to its original shape by passing wool yarn through it just like as in rounding aworn knuckle. In the.case where the whippens are obsolete and the cushion felts are deeply grooved, then the only solution is to replace just the whippen felt. I might add, that if such a piano was thrown into my hands, I would try to procrastinate doing the work until the owners junked the piano!

24) Polish the capstans. The top action is still off the keyframe, so the keys are readily accessible. Either buff them on a buffing wheel or if on the job away from the shop, take some chrome/ metal polish along with a rag and polish them a section at a time. Just use a wooden block along the back of the keys to keep them level and from wiggling too much. After polishing, I like to spray the capstans with emralon.

25) Clean knuckles and backchecks. A good shop will have a portable air compressor as a part of the essential equipment. Take the nozzle and blow with high pressure up and down the knuckle and backchecks. Of course, it goes without saying that the entire action should be blown out, but I like to use a higher pressure when cleaning the leather. If the knuckles are dirty with graphite, this must be cleaned off next. Use some sort of a solvent, whatever is available in your area (some say that Renuzit is still available, but I can’t get it). Then take a suede brush and comb the leather. Check the hammer tails. If they are not rough enough to ensure good backchecking, use a hand file and correct. Be careful not to roughen the tails so coarse as to wear the back checks abnormally.

This ends section II. Before proceeding onto section III, make sure that all needed repairs have been finished and that sections I and II were performed accurately. Remember that if two people are working in the shop together, one can do section I while the other works on section II. 

III. ALIGNMENTS (install action back on keyframe)

26) Align action frame in piano (adjust keyframe stop block). The action parts must all line up to insure full power and reliability. Take as samples the action parts to the keys at the ends of each section. Starting at the strings and working down, align the parts to the strings. This is assuming that the strings are in proper alignment. If the piano has been restrung, or especially if the plate has been removed, this may not be the case. Where there are agraffes or some other string positioning devices, you can be pretty sure that the strings are aligned well, assuming the plate is OK. Too many “technicians” try to install pinblocks and soundboards when they do not know how to align them. If you have trouble aligning the action and can see the piano has been “rebuilt,” the problem may be that the piano was not properly rebuilt. Anyway, loosen the hammerflange screw to align the hammer to the string. Next, align the balancier so it is directly underneath the knuckle. This is done by either loosening the whippen screw and tilting the whippen or else shimming the flange and rotating the whippen. More will be said on this subject in step 28.

After the sample keys are aligned, check to see how the hammers look in relation to the strings. If all of the hammers are off to the left (most usually) or off to the right, then the stop block at the left end of the keyframe must be adjusted. It normally is screwed into the case, so just remove it, install or subtract shims, and screw back.

Shimming the stop block is normal, because the felt often compacts from the action coming back after using the una corda pedal. Make sure you check this if the piano has been stored for a time on its side, since the weight of the action against the stop block compresses the felt. If the shims need to be removed, as would be the case if the capstans are off to the right, be careful. Something has caused this and should be corrected.

There is the far chance that the action was improperly aligned in the factory, but not often. If the hammers have been replaced poorly and the hammer angle or hammer travel are way off, check here. More likely, check to see if the pinblock has been replaced. If the string alignment has been changed through altering the plate, not only will the action not line up, but the dampers will not, and the sidebearing on the bridge pins will be excessive.

As a caution, check to see if the capstans were centred in the keys, or that the keys are properly spaced and not warped on the samples being used. Is the action positioned on the keybed correctly? Since the bass strings cross the tenor at an angle, pulling the action in and out will change the hammer to string alignment a little. As a final check, did you rotate the whippen flanges when they should have been tilted, or vice versa? Remember to favour the strings which have agraffes when choosing where to align, since the upper treble strings with a V-bar can be slightly aligned to the action.