Pianotech

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Bell Screw Removal

  • 1.  Bell Screw Removal

    Posted 03-28-2019 16:21
    I have a piano in my shop that was made by a well-known manufacturer in NY. It has this cast iron lump of a growth mounted on the rim in the treble area. It is attached to the rim with a goodly number of screws. I wish to do a rim lumpectomy. Most of the screws were removable, but several - including the ones that go into the side of the rim are really in there firmly. I'd use a hammer screwdriver to remove them, but there is really no way to get in there with such a tool. Any suggestions on how to remove them? I guess I could drill them out - if I had a right-angle drill (I don't).

    ------------------------------
    Terry Farrell
    Farrell Piano Service, Inc.
    Brandon, Florida
    terry@farrellpiano.com
    813-684-3505
    ------------------------------


  • 2.  RE: Bell Screw Removal

    Posted 03-29-2019 15:09
    Do you have a large screwdriver that has a square shank on which you can put a crescent wrench?
    --David Nereson, RPT

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    David Nereson
    Registered Piano Technician
    Denver CO
    303-355-5770
    ------------------------------



  • 3.  RE: Bell Screw Removal

    Posted 03-29-2019 15:38
    I have a grand piano made in Ohio that I am looking for a  clump of treble steel, could you send it to me once you successfully extricate it?

    ------------------------------
    Troubles are Bubbles, and they just float away.
    chernobieffpiano.com
    grandpianoman@protonmail.com
    Knoxville, TN
    865-986-7720
    ------------------------------



  • 4.  RE: Bell Screw Removal

    Posted 03-29-2019 16:37
    Not sure I can do that Chris - I was thinking of keeping it next to my bed table for home defense!

    ------------------------------
    Terry Farrell
    Farrell Piano Service, Inc.
    Brandon, Florida
    terry@farrellpiano.com
    813-684-3505
    ------------------------------



  • 5.  RE: Bell Screw Removal

    Posted 03-29-2019 16:36
    Hi David. Yes I do, and I tried that. It is difficult to get in there to put enough inward pressure on the screwdriver to keep it from popping out of the slot. That's why an impact screwdriver - or rather a 90-degree impact screwdriver would be just the ticket!

    ------------------------------
    Terry Farrell
    Farrell Piano Service, Inc.
    Brandon, Florida
    terry@farrellpiano.com
    813-684-3505
    ------------------------------



  • 6.  RE: Bell Screw Removal

    Posted 03-29-2019 17:04
    Terry, maybe you could cut it out with a side grinder and chisel?
    Btw, how are you going to support the nose bolt?

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    Steven Rosenthal
    Honolulu HI
    808-521-7129
    ------------------------------



  • 7.  RE: Bell Screw Removal

    Posted 03-29-2019 17:42
      |   view attached
    Hi Steven - what do you mean by a "side grinder"? An angle grinder?

    As for the nose bolt, I'll install a new belly brace to support the belly rail and the nose bolt can be mounted right in the new brace. See picture below:

    ------------------------------
    Terry Farrell
    Farrell Piano Service, Inc.
    Brandon, Florida
    terry@farrellpiano.com
    813-684-3505
    ------------------------------



  • 8.  RE: Bell Screw Removal

    Posted 03-29-2019 18:19
    Beautiful work Mr. Farrell,

    In all seriousness I hope when you are finished you'll take the time to grind the original makers name off of the string frame. While I expect the finished product will be a beautiful piano it will bear very little more than a passing resemblance to the instrument as built in New York. Keeping the original name anywhere on an instrument with this level of modification lends credence to the argument currently being made by a New York manufacturer that they alone can restore pianos made in their factory. To be clear I am not arguing the wisdom of or your right to be making such modifications. Just suggesting that you take pride in your design and put your own name on it.

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    Karl Roeder
    Pompano Beach FL
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  • 9.  RE: Bell Screw Removal

    Posted 03-29-2019 19:17
    Edited by Jim Ialeggio 03-29-2019 19:28
    Strike that..<G>

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    Jim Ialeggio
    grandpianosolutions.com
    Shirley, MA
    978 425-9026
    ------------------------------



  • 10.  RE: Bell Screw Removal

    Posted 03-29-2019 20:42
    Terry, yes, an angle grinder. I had another thought, slightly less destructive, using a die grinder to remove the heads of the screws.

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    Steven Rosenthal
    Honolulu HI
    808-521-7129
    ------------------------------



  • 11.  RE: Bell Screw Removal

    Posted 03-29-2019 22:57
    A heat gun played over the head of inextricable screws  for a  minute or so has always worked for me to loosen them up

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    Martin Snow
    Boston MA
    617-543-1030
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  • 12.  RE: Bell Screw Removal

    Posted 03-29-2019 23:33
    Mr Farrell,
    I was wondering that myself. When you make these kinds of modifications, do you take the original manufacturers name off and put your name on it? That would seem a fair proposition yes?
    -chris

    ------------------------------
    Troubles are Bubbles, and they just float away.
    chernobieffpiano.com
    grandpianoman@protonmail.com
    Knoxville, TN
    865-986-7720
    ------------------------------



  • 13.  RE: Bell Screw Removal

    Posted 03-30-2019 08:33
    Chris C. asked: "When you make these kinds of modifications, do you take the original manufacturers name off and put your name on it?"

    I wouldn't mind doing that - IF I had a custom decal. But I don't, so I won't. A Ford Mustang with a custom engine, aftermarket transmission, rear end, clutch and suspension is still a Mustang - is it not?

    ------------------------------
    Terry Farrell
    Farrell Piano Service, Inc.
    Brandon, Florida
    terry@farrellpiano.com
    813-684-3505
    ------------------------------



  • 14.  RE: Bell Screw Removal

    Posted 03-31-2019 01:08
     A Ford Mustang with a custom engine, aftermarket transmission, rear end, clutch and suspension is still a Mustang - is it not?

    No, wouldn't that be a mule?





    ------------------------------
    Troubles are Bubbles, and they just float away.
    chernobieffpiano.com
    grandpianoman@protonmail.com
    Knoxville, TN
    865-986-7720
    ------------------------------



  • 15.  RE: Bell Screw Removal

    Posted 03-31-2019 02:23
    Well, let's flip it. If you took a stock Mustang and replaced the body with a different design custom body. What would it be then?
    It really depends on whether the observer is interested in the mechanics or the look. Also the Mustang is in a category of cars that have a history of being customized. Ford even contributed by allowing the Shelby Mustang to be built by Shelby American for the first 3 years, then Ford took production over.

    Grand pianos aren't differentiated by an intrinsic visual design, they distinguish themselves by the mechanical design.

    The reason for the conversation is that Steinway has been able to greatly add to the value by virtue of their brand name and this extends to their pianos of any vintage, so resellers benefit as well. They have good reason to be protective of the brand, but clearly there are limitations. Imho they are over reaching by a long shot, they should be bigger than this.

    The kind of work you folks are doing is in another category altogether I would think. More remanufacturing rather than rebuilding or restoring. I think it represents a new era in the field. The pianos are truly hybrids.

    Quite impressive!

    ------------------------------
    Steven Rosenthal
    Honolulu HI
    808-521-7129
    ------------------------------



  • 16.  RE: Bell Screw Removal

    Posted 03-29-2019 23:45
    The bell is not for supporting the plate.  If you look at the threads on the bolt where it exits the bell they can only pull the plate downward.  It is used to tweak down bearing.  According to what  Frank Urich told me while teaching me to install a soundboard in the Steinway rebuilding facility in 1989, the "belly rail brace" is designed to always be under tension.  It doesn't need to be bigger.  That's what he said

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    Glen Hart
    Grand Junction CO
    970-434-5558
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  • 17.  RE: Bell Screw Removal

    Posted 03-30-2019 08:44
    Glen H. wrote: "the "belly rail brace" is designed to always be under tension.  It doesn't need to be bigger."

    I don't understand what you are addressing here. What belly rail brace are you talking about. Surely he is not talking about the one I installed......  And what do you mean by bigger? What doesn't need to be bigger than what?

    ------------------------------
    Terry Farrell
    Farrell Piano Service, Inc.
    Brandon, Florida
    terry@farrellpiano.com
    813-684-3505
    ------------------------------



  • 18.  RE: Bell Screw Removal

    Posted 03-30-2019 08:38
    Martin and Steve - THANKS!!!! Yes, those sound like two great doable approaches. First I will try heat (very easy to do). If that doesn't work, I can grind the heads off. Grinding heads off may or may not work - the screws may be installed in a non-parallel orientation.

    ------------------------------
    Terry Farrell
    Farrell Piano Service, Inc.
    Brandon, Florida
    terry@farrellpiano.com
    813-684-3505
    ------------------------------



  • 19.  RE: Bell Screw Removal

    Posted 03-30-2019 00:40
    While I don't modify pianos in the same manner as Mr. Farrell shows, I don't buy the argument that he should rename the piano after himself.

    When one sends an old Steinway to NY to be rebuilt, you do not get a piano back that matches original specs. And if you buy a new Steinway, you do not get one that matches the full Steinway DNA of the past. The reduced leverage in the action and the heavier hammers are new "genes". The narrower agraffes, smaller diameter treble bridge pins and lighter bridge "genes" are extinct. And the mishaped V-bars are probably still there. Not to mention the uglier Hamburg case style that has now fully infected the company.

    Modifying an old Steinway when one rebuilds it does not degrade the Steinway brand even if it does degrade the piano for some people. This notion is a false equivalency often promulgated by those intent on deceit. No one is confused about who is responsible. Steinway has no responsibility to pianos out of warranty.

    And what if the modifications are based on the company DNA and are evolved further to perfect the design intent? This opens up the possibility of a rebuilt Steinway to being the only state of the art Steinway available.

    Because no design innovation is thought possible at Steinway. (They say it is already the most perfect piano design ever made.) If so, why do Steinway techs stuff felt into noisy duplexes? If the design is perfect, why does it sometimes have problems like that?

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    Edward McMorrow
    Edmonds WA
    425-299-3431
    ------------------------------



  • 20.  RE: Bell Screw Removal

    Posted 03-30-2019 03:55
    There are some nose bolts and plate screws, mostly on very old pianos, before things became more standardized, which have a flat head with two holes, like the face of a watch, with holes at 3 and 9 (or any two diametrically opposed numbers).  The holes are set in from the outer edge of the screw head, but not by much, and they're usually about an eighth-inch diameter hole, or slightly smaller.  These screws take special wrenches, some of which are shaped like a slingshot or wishbone or a pair of opened pliers, with short (1/8 inch long or so) studs, prongs, nibs, pins or whatever they're called, mounted in the ends of the two "slingshot" arms and of course spaced the same distance apart as the two holes in the screw head.  Takes way longer to describe than to draw.
            Now, if you drilled two holes in the screw head and made a "wrench" by mounting two short pins (hitch pins, bridge pins) press-fit into holes drilled into a flat piece of iron or steel serving as a handle, I wonder if you could get enough leverage (torque) to back those suckers outta there?  Or, instead of drilling holes in the screw head, maybe two pins of a diameter the same as the slot in the screw head, mounted as close as is practical to the outer edges of the screw head.  (I'm assuming these are standard flat-head wood screws)
    --David Nereson, RPT





  • 21.  RE: Bell Screw Removal

    Posted 03-30-2019 08:36
    I understand what you are saying Karl. IMHO, it just doesn't matter either way. In this particular case, I did the belly work for a client. So whatever kind of decal they choose to have on it when it is refinished is their business.

    ------------------------------
    Terry Farrell
    Farrell Piano Service, Inc.
    Brandon, Florida
    terry@farrellpiano.com
    813-684-3505
    ------------------------------



  • 22.  RE: Bell Screw Removal

    Posted 03-30-2019 08:00
    Terry,

    Have you tried using a slotted screwdriver bit on a ratchet handle? Most of the bits that I've seen that are used with an impact driver (the type you hold in your hand and hit with a hammer) have a 1/2" square drive that will fit on the ratchet handle. Better yet, mount it on a breaker bar for more leverage and less chance of damage to the pawls.

    Allan

    ------------------------------
    Allan Gilreath, RPT
    Registered Piano Technician & President
    Allan Gilreath & Associates, Inc
    Calhoun, GA
    706-602-7667
    allan@allangilreath.com - www.allangilreath.com
    ------------------------------



  • 23.  RE: Bell Screw Removal

    Posted 03-30-2019 08:23
    Have you considered that maybe it's not supposed to come out !!
    The defiance of these few screws should tell you something...
    Don't Mess with the Best

    A little penetrating oil perhaps to break the corrosion?

    ------------------------------
    Regards,

    Jon Page
    mailto:jonpage@pianocapecod.com
    http://www.pianocapecod.com
    ------------------------------



  • 24.  RE: Bell Screw Removal

    Posted 03-30-2019 08:58
    Jon P. wrote: "Have you considered that maybe it's not supposed to come out !! The defiance of these few screws should tell you something..."

    Well, most HAVE come out - and several of those were VERY difficult. So yes, they should be able to be removed.

    "Don't Mess with the Best"

    ???????????

    "A little penetrating oil perhaps to break the corrosion?"

    Might be tough to get it in there, but sure, can't hurt.

    ------------------------------
    Terry Farrell
    Farrell Piano Service, Inc.
    Brandon, Florida
    terry@farrellpiano.com
    813-684-3505
    ------------------------------



  • 25.  RE: Bell Screw Removal

    Posted 03-30-2019 08:55
    Thanks for the ratchet/breaker bar suggestion Allan. It will tend to have the same problem of the blade tending to want to pop out of the slot, but maybe after heating and getting some real good leverage on it - maybe that might do the trick. Also, maybe I can wedge a piece of wood or something in there to jam the screwdriver head in the screw slot.

    Somehow, with all these great ideas, I think I'll get this sucker off!

    ------------------------------
    Terry Farrell
    Farrell Piano Service, Inc.
    Brandon, Florida
    terry@farrellpiano.com
    813-684-3505
    ------------------------------



  • 26.  RE: Bell Screw Removal

    Posted 03-30-2019 19:01
    I vote for HEAT.  Also you can deepen the screw slots with a mototool. Should lessen the skip out.

    Pwg

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    Peter Grey
    Stratham NH
    603-686-2395
    pianodoctor57@gmail.com
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  • 27.  RE: Bell Screw Removal

    Posted 03-30-2019 22:09
    Terry, maybe after you've heated the screws you can feed some paraffin that might run along the screws. Also when you're ready to try to unscrew them you might try chilling the screws/housing. Those cans of air for electronics will shoot out frost if held upside down. It may well be that the hangup is between the screws and the cast iron, you might need all the shrinkage you can get.
    From the pictures I've been able to find it looks like the new ones screw straight in w/square headed bolts. The older ones w/slotted screws appear to be not parallel. If you cut off the heads you might at least be able to get a sawzall  behind the bell. Or use a crowbar or something. Nasty business.
    Harbor Freight has a right angle pneumatic drill or die grinder for $37, not sure if it has an advantage over the breaker bar idea. But hey, new tool!

    ------------------------------
    Steven Rosenthal
    Honolulu HI
    808-521-7129
    ------------------------------



  • 28.  RE: Bell Screw Removal

    Posted 04-01-2019 19:41
      |   view attached
    Mission Accomplished! A combination of deepening the slot of one screw with a Dremel tool, heat on that same screw and a screwdriver blade held in a pair of vice grips did the trick. Thanks for all the suggestions.

    ------------------------------
    Terry Farrell
    Farrell Piano Service, Inc.
    Brandon, Florida
    terry@farrellpiano.com
    813-684-3505
    ------------------------------



  • 29.  RE: Bell Screw Removal

    Posted 9 days ago
    If the goal and purpose of the modification is to have more volume and projection up in the high treble. Then removing the cast Iron bell and adding the pinblock mass in not achieving that goal acoustically, if you shorten the rib lengths and add to the rib heights (making them more stiff).
    The reason is because the shallow bending waves after bouncing off the rim would create low standing waves. Thus low volume.  Keeping the cast iron bell (which is further attached to mass of the string frame) along with the original rib scale would produce more volume. The lower rib profiles are creating a more powerful bending wave and thus a stronger standing wave ( = more board movement).
     Now if you add the pinblock mass to the treble and keep the original rib scale (by lowering the pinblock mass so the ribs connect into the original notches) then you may have more power development.
    -chris

    ------------------------------
    Troubles are Bubbles, and they just float away.
    chernobieffpiano.com
    grandpianoman@protonmail.com
    Knoxville, TN
    865-986-7720
    ------------------------------