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Old upright strike line

  • 1.  Old upright strike line

    Member
    Posted 05-18-2019 01:42

    I am replacing hammers, shanks and butts on an old upright (Hobart Cable) with a brass rail.   I was planning on following the existing strike line, but in the top 10 or so bass notes the old shanks were tilted pretty dramatically to align to the strings.  Altering the strike line now would allow for less of a tilt.  Is this a reasonable idea?  How big an impact on tone would a few millimeters have in this section? 

    Thanks for your insight!
    Amy



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    Amy Baldinger
    Vashon WA
    206-459-7672
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  • 2.  RE: Old upright strike line

    Registered Piano Technician
    Posted 05-18-2019 07:12
    From memory, 2 mm down from the bearing bar on note 88 is the optimum strike point.

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    Larry Fisher
    Owner, Chief Grunt, Head Hosehead
    Vancouver WA
    503-310-6965
    Working the gravy zone for the rest of my days.
    ------------------------------

    Original Message


  • 3.  RE: Old upright strike line

    Posted 05-18-2019 07:42
    Treble tone is hugely effected by the strike line especially from note 60-ish through 88. I don't make any assumptions about the factory's intent when laying out the strike line. I use these ratios, which I got a while ago from Ed Mcmorrow...they work quite well without reglueing samples to find the line.

    88 = SL * .064
    83 = SL * .075
    78 = SL * .085
    73 = SL * .089
    68 = SL * .094
    63 = SL * .099

    graduate straight line from 63 to 1 
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    Jim Ialeggio
    grandpianosolutions.com
    Shirley, MA
    978 425-9026
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    Original Message


  • 4.  RE: Old upright strike line

    Registered Piano Technician
    Posted 05-18-2019 07:44
    Amy,

    Do you mean that the shanks are not vertical, but rather leaning towards the left (or right)?  If so, then the hammers were "shanked" prior to installation, and the butt portion was shaved to allow tilting as far as needed.  Pretty standard factory procedure.

    If you are describing something else then that's a different story.

    You would be wise to follow what is there since it was done for a reason. Otherwise you may end up complicating things beyond your ability to resolve. 

    Can you post a picture?

    Pwg

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    Peter Grey
    Stratham NH
    603-686-2395
    pianodoctor57@gmail.com
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    Original Message


  • 5.  RE: Old upright strike line

    Posted 05-18-2019 08:56
    Looking at the OP I see treble was not the question.  I would use corrected ratios anyway in the treble, if it were me.  Regarding your question, I stand by the main concept of my original post...assume nothing.

    The shanks were tilted to accommodate an aggressive miss-match between flange hole placements in the action stack, and as-built string locations as per the design strike line...ie, they blew it big time. Your plan has a decent chance of working, but you would need to tonally prove you were not losing too much by changing the low end strike line. There is more strike line leeway in the low bass as opposed to the high treble, so I think you have a reasonable shot at success.

    As for the supposed "wisdom" of factory floor, assumed perfection, factory floors are factory floors. Workers have very limited time to complete their process. If various parameters which effect their process are out of wack, there is no time to go back and correct. You accommodate the inaccuracy as quickly as you can, and then tell the marketing guys its a unique, patent-able, transcendent feature, which then makes the marketing guys salivate. It wasn't planned...it happened

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

    Original Message


  • 6.  RE: Old upright strike line

    Registered Piano Technician
    Posted 05-18-2019 09:14
    It can be as simple as two or three different models of upright, but one brass rail configuration. They "made it work". 

    Nonetheless, if you mess with it too much you need to KWYADAWYADI (know what you are doing and why you are doing it). 

    Pwg

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    Peter Grey
    Stratham NH
    603-686-2395
    pianodoctor57@gmail.com
    ------------------------------

    Original Message


  • 7.  RE: Old upright strike line

    Registered Piano Technician
    Posted 05-18-2019 10:56
    Aw geez Amy, I totally missed the word bass in your post.  As usual my reading comprehension is lacking focus.

    Peter and Jim have covered things nicely.  The amount of tilt in the hammer at the top of the bass section is not that critical of tone but rather a function of clearance and hitting the strike line. 

    As for rake  ...  the amount of tilt fore and aft (as opposed to left to right) is also a function of physical fit and finding that strike line.  The strike line may not be that critical in that area of the piano but being able to clear the dampers enough to let the dampers do their job at the most effective spot on the string IS.  Don't mess with that unless you're ready to spend lots of time in the trial and error department.

    Good luck and I hope your work is worth it in the end.  These old pianos can really deliver if you give them what they need to have.

    Lar


    ------------------------------
    Larry Fisher
    Owner, Chief Grunt, Head Hosehead
    Vancouver WA
    503-310-6965
    Working the gravy zone for the rest of my days.
    ------------------------------

    Original Message


  • 8.  RE: Old upright strike line

    Posted 05-18-2019 14:44
    Your next question to post will be: How do I repair broken brass rail tongues?
    Learning experience aside, is this project worth it?
    It might be a bigger can of worms than you want to chew.

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    Regards,

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

    Original Message


  • 9.  RE: Old upright strike line

    Posted 05-18-2019 16:02
    When taking on jobs, I would ask myself: Can I do this?
    After ending up working for peanuts all too often; I now ask myself;
    Should I do this?

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    Regards,

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


  • 10.  RE: Old upright strike line

    Registered Piano Technician
    Posted 05-18-2019 18:42
    And when the new brass butt plates have to be individually either filed to fit, or the cutout needs to be hammered closed slightly for each one...or the brass tongues need to be filed to fit the new butts...

    When I say: "Yes, I can do it, but with the possible complications involved it could easily end up being somewhere in the vicinity of between  $x,000.00 and $y,000.00...that usually decides it. 

    Pwg

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    Peter Grey
    Stratham NH
    603-686-2395
    pianodoctor57@gmail.com
    ------------------------------

    Original Message


  • 11.  RE: Old upright strike line

    Member
    Posted 05-19-2019 11:35
    Thanks for the tips everyone.  I will raise the top bass line a tad and meet up with the established treble line.  I think that will work ok.   

    And Peter - I appreciate your warnings.  The project has gone pretty smoothly so far, even with having to shape some of the new butt plates to fit.   I've estimated generously so I'm covered for some overage. The rest I'll count as learning time.  And I'm still having fun!

    Amy

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    Amy Baldinger
    Vashon WA
    206-459-7672
    ------------------------------

    Original Message