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         50. 
Piano Pin Block  Separating from Frame     
We sell new pin blocks of exceptional quality,   from both US and German 
suppliers.      Replacing a pin block is a very difficult task. It is 
one of the most precise and skilled jobs in piano repair, and a blunder can be 
very costly. You know that you probably need a new pin block when several tuning 
pins are so loose that they won't hold, even after all desperate repairs to the 
tuning pins have been tried. I will say that a handful of our online customers 
have replaced pin blocks themselves, but you should send 
me e-mail to learn what is involved so that you can determine if the task 
is beyond your skill lever.  Grand pianos can have separation, but it 
is not as serious, as a rule, since the pins are not pulling in a way to drag 
the pin block on out of the piano. It would be possible to bolt a grand pin block 
solid in the same way as the upright below, but it would really look crazy, and 
some very special tools would be needed to drill from under the pin block and 
recess the nuts. Just forget it please :-)      A 
separating pin block is identified in this way--   Upright Piano Only 
  
     With 
the (upright) piano top open, look at the top of the metal and wood frame. (If 
your piano has a felt piece covering the top of the pin block and frame, remove 
it.) From front to back, you see the metal frame, then the top of the pin block, 
and then the upper part of the massive wood frame that goes all the way to the 
bottom of the piano behind.  
  When a pin block begins to separate, you 
will see a crack between the pin block wood and the wood of the frame. This usually 
is worst in the center of the piano. A thin crack should be measured and checked 
every six months. An automotive "feeler gauge" could be used for an accurate check 
each time.   If the crack is slowing opening, you better get to work 
on it. If it has opened quite a bit-- one sixteenth to a quarter inch, a mild 
panic would be in order. A half inch or more-- Call the tuner. It's probably gone. 
Be ready for bad news. The problem is, when the pin block bows too far, it will 
also crack vertically through the tuning pin area, the worst being in the center 
where the pins are close to the top of the pin block.    So, 
the crack is not too wide, and it may be in two places along the top. It is very 
likely that you can make the repair that will last until you pass the piano on 
in your will to the kid. Then he can worry about it. So, here it goes...  
    ILLUSTRATIONS: 
  The upper left graphic is a very 
old Straube/Hammond Upright Grand. It is hard to tell if there is a harp coming 
to the top of the piano or if it stops below the pin block. When the pin block 
is open with no harp securing it, the situation is very critical, for the block 
could break out at any time. I suggested my customer, Charles Lewis, add two bolts 
to this piano. They should be to the right and left of the middle bolt in front 
of the red arrow, and placed half way to the bolts to the right and left. This 
should be done first, then the old bolts replaced. The new bolts should not be 
brought up tighter until ALL bolts are replaced. As elsewhere in this section, 
don't draw the bolts all the way up if you sense the pin block wants to crack. 
Securing the pin block is the priority, and the crack can be left part way open. 
 The graphics with the maroon felt top cover are of 
a Baldwin. The felt is sometimes a factory feature, but it is sometimes added 
by crooked piano stores to hide the separation of the pin block from the wood 
frame. Before buying a used piano with a felt cover of the pin block, run your 
finger along the point where the pin block and frame meet. If a groove is pronounced 
and easy to indent along the line with your 
fingernail, refuse to buy the piano unless they remove the felt part way along 
the top for examination. If they refuse, run for the door fast. Never buy such 
a piano, no matter what they promise. Refuse it if they offer to repair it.  
    Get 
these tools A sturdy "C" clamp that will open wide enough 
to go over the top of the piano. A monster screw driver. Buy, at the hardware 
store, four three eighths inch hex head "stove" bolts at least an inch longer 
than the top of the piano is deep. Get one hex nut and two one inch washers for 
each bolt. You will need a regular three eighths inch drill bit, longer than the 
piano top is deep, and a drill motor. Two wrenches the size of the bolt heads 
and nuts. Also, find or buy a one inch minimum flat wood bit.    Check 
out the Diagrams before you go on to do the repair. 
      Please 
follow my instructions precisely FIRST, (having removed 
the lid) clamp the top of the piano with the "C" clamp snugly but not tight. Do 
this near one of the big screws at the top where the crack is. All you want is 
control.    SECOND, With the big screw driver, remove the wood screw 
at that point.  If it has a hex head lag bolt, use your end wrench.  
   THIRD, Chuck the regular three eighths inch drill bit, and drill out 
the hole where the screw was, working from the inside of the piano. Drill the 
hole out the back of the piano. You are drilling through very old hard wood, so 
go slowly, and pull the drill bit out from time to time to clean out the shavings. 
The drill bit will heat up enough to snap it if you just lean on it and don't 
let off.  Be very sure you are drilling on the level. Ask a friend to stand 
to the side to tell if you are on the level. If you are a politician this is hopeless, 
of course :-)   FOURTH, Go around back, and use the one inch flat bit 
to recess the hole at least three fourths of an inch. The bit will flop around 
a bit, but this is the order I have found I have to use. The only alternative 
is to run a lead hole through from the inside with a 1/8 inch long drill. Use 
the first hole from the back of the piano for control, and recess the hole in 
back with the flat wood bit, then run the 3/8 inch drill through, using the 1/8 
inch hole as a guide. This long method gives better control of the flat wood bit 
and a bit cleaner recess.   FIFTH, Put a washer under the head of the 
bolt, and push it through the hole BACK TO FRONT, OUTSIDE TO INSIDE. Tap the bolt 
and washer down snug into the recessed hole.  Put the nut on the bolt inside 
with the washer, and tighten it snug, NOT tight. You DO NOT, DO NOT, DO NOT, DO 
NOT, DO NOT, DO NOT want to close the crack up!!!!!!!. If you try to close the 
crack, you will crack the pin block worse than before. It is warped and dry from 
many years of being in that position, and all you want to do is stop the movement. 
Close the crack, and you deserve all the pain you get. How else can I say it? 
   For a precise treatment, check the crack with an automotive feeler 
gauge as you tighten the nut.  Add blades of the feeler gauge until they 
are snug in the crack.  When the crack starts to tighten on the feeler gauge 
as you check it, STOP there.  You are tight enough.     If 
the washer under the nut will not sit flat-- if it wants to hang up on the casting 
of the metal harp next to the hole, go find a grinding wheel, and grind it so 
that it fits flat under the nut. Do not try to bend it into place by tightening 
the nut.    SIXTH, Remove the "C" clamp, move to the next screw in the 
cracked area, and repeat the process. Seldom will you have to do the two extreme 
right and left hand screws. However, if the top wood structure is cracked at the 
ends, the two end ones must also be done.    SEVENTH, If your bolt ends 
stick out pretty far into the piano, you would be kind to the tuner to cut the 
ends off with a hack saw or Dremel tool.    EIGHTH, If you used hex head 
bolts, DO NOT fill the holes in the back with anything. You may put a removable 
plug in them. You might need to tighten the replaced bolts some day, and you would 
need to get your socket on the bolt heads. I prefer stove bolts. The square shoulder 
will embed into the washer, and the thing will not go anywhere. But, after a year, 
snug the nuts up a bit since the stove bolt could give a bit and sink deeper. 
  Now, that wasn't so bad was it? I suggest that you do all of the screws 
with new ones if it looks at all questionable. Why leave a couple? Make the whole 
thing secure so you can forget about it for the next 150 years.       
 Freak 
SituationHere is a case where the pin block and 
harp stayed reasonably straight, but the frame separated. In this case, do the 
bolt repair above, but do all the bolts without tightening them. Once the bolts 
are in place, tighten them in many steps, going back and forth among the bolts. 
This way the pin block and harp may not break if you move them back and keep them 
from bowing.   Dear 
piano manufacturers Why don't you arrogant people put bolts 
all the way through the top at the factory? A good piano should last for 80 years. 
By putting in those wood lag screws, you are admitting that you don't really care 
about the last 40 years of its life. Wake up please! AND, I salute the hand full 
of piano makers who DO bolt the top solid.            
    
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