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William de Blaise wire scale

  • 1.  William de Blaise wire scale

    Registered Piano Technician
    Posted 09-20-2018 16:14
    I have a bit of a head scratcher with the wire scale on my William de Blaise harpsichord. Look at the attached picture of the numbers on the wrestplank that note the wire scale. (I'm fairly certain these numbers are original from the de Blasie shop.) In the base the numbers are 20, 21, 22, 11, 10, 9, etc. The micrometer reading are as follows (the wire appeared to be original): 20 = .028, 21 = .032, 22 = .035, 11 = .026. Also note on the other picture the significant jog of the 8' bridge at the bass end. (The 6 lowest notes are on the jog.) In spite of the jog, the speaking length gets shorter as you go up from note 1. All the wire is yellow brass.

    I am not up on harpsichord wire scaling but this is something I have never seen. Why would the diameter get larger going up and then drop back down at note number 8?

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    [Don] [McKechnie,] [RPT]
    [Piano Technician]
    [dmckech@ithaca.edu]
    [Home 607.277.7112]
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  • 2.  RE: William de Blaise wire scale

    Posted 09-21-2018 08:12
    Hello Don

    My William deBlaise is a model A (No.632) which is single manual and small enough to fit just nicely under my Model 'A' Hamburger S&S.
    What is yours?

    Michael Gamble

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    Michael Gamble
    semi retired
    Brighton
    01273813612
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  • 3.  RE: William de Blaise wire scale

    Registered Piano Technician
    Posted 09-21-2018 10:19
    Bizarre! One has to speculate that he experimented, and thought it sounded better that way. You might want to join the Facebook Harpsichord group and ask the question there. Someone is bound to have worked on de Blaise harpsichords (7800 members, with technicians and builders who are quite active in writing and responding). 
    Regards,
    Fred Sturm
    "The true sign of intelligence is not knowledge, but imagination." - Einstein






  • 4.  RE: William de Blaise wire scale

    Registered Piano Technician
    Posted 09-21-2018 14:00
    Hi Michael,

    I am guessing the model A is the same as his "cembalo traverso" model? (See the attached picture of my instrument.) Carey Beebe sells a reprint of the de Blaise Service manual so I purchased a copy. (see photo) There are no pictures to go along with the service descriptions of each instrument in the manual but the model A is the only one that fits the registration description of my instrument. The serial number on my de Blaise is 155.

    Are there numbers for the string scale on the wrestplank of your model A? Are the the same numbers as mine in the bass?

    Best,
    Don

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    [Don] [McKechnie,] [RPT]
    [Piano Technician]
    [dmckech@ithaca.edu]
    [Home 607.277.7112]
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  • 5.  RE: William de Blaise wire scale

    Registered Piano Technician
    Posted 09-21-2018 14:16
    Hi Fred,

    It is bizarre! In the Zuckermann book there is mention about how a workman at the de Blaise shop apparently put the 8' bridge in the wrong location (2 inches further back than the drawing) but then de Blaise decided it needed to be back that far. One wonders how he deduced that was the correct placement!

    I sent some questions to the Malcolm Rose shop and still waiting a reply. It looks like that is the only shop where I can get wire close to the thickness I would need if i'm going to try the original spec. American Piano Supply used to sell thick brass wire but I cannot find anyone selling thicker brass wire in the US. I will give that Facebook group a go.

    Best,
    Don

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    [Don] [McKechnie,] [RPT]
    [Piano Technician]
    [dmckech@ithaca.edu]
    [Home 607.277.7112]
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  • 6.  RE: William de Blaise wire scale

    Posted 09-23-2018 06:48

    Michael Gamble <mg@magfilms.co.uk>

    22 Sep 2018, 07:38 (1 day ago)
    to DoNotReply
    A friend of mine (now long dead, unfortunately), John Paul wrote a book "Modern Harpsichord Makers - Portraits of nineteen British craftsmen & their work". He sent me a copy. Published by Victor Gollancz in 1981, ISBN 0 575 02985 4 . It contains information about William deBlaise on page 181 and a photo of his two-manual 'triangular' H'chord like the Model 'A' but with two manuals on page 180. I have seen this book available on Amazon. Malcolm Rose is also in the list of contents.






  • 7.  RE: William de Blaise wire scale

    Posted 09-24-2018 07:58
    Hi, Michael,

    Thank you very much for posting this.

    I've looked for this book; but, because of the swampy nature of my
    alleged mind, could never quite remember either the author's name; or
    enough of the actual title. Now, thanks to your eminent self, my very
    own copy is on it's way from Abacus.

    Thanks again.

    Kind regards.

    Horace

    On 9/23/2018 3:47 AM, Michael Gamble via Piano Technicians Guild wrote:
    > Please do not forward this message due to Auto Login.
    >
    > Michael Gamble <mg@magfilms.co.uk <mg@magfilms.co.uk>>22 Sep 2018, 07:38 (1 day ago) to DoNotReplyA friend of mine (now long dead, unfortunately), John Paul wrote a book "Modern Harpsichord Makers - Portraits of nineteen British craftsmen & their work". He sent me a copy. Published by Victor Gollancz in 1981, ISBN 0 575 02985 4 . It contains information about William deBlaise on page 181 and a photo of his two-manual 'triangular' H'chord like the Model 'A' but with two manuals on page 180. I have seen this book available on Amazon. Malcolm Rose is also in the list of contents.
    >
    >
    >


  • 8.  RE: William de Blaise wire scale

    Registered Piano Technician
    Posted 09-24-2018 09:56
    Hi Michael,

    You mentioned this book to me a while back and I did purchase a copy from Amazon. Very informative and thanks for the recommendation. It is interesting to read how Martin Huggett describes the personality of de Blaise as opposed to the description in Zuckermann's book. No doubt though that de Blaise was firmly on the side of the 20th century idea of harpsichord construction.

    Best,
    Don

    ------------------------------
    [Don] [McKechnie,] [RPT]
    [Piano Technician]
    [dmckech@ithaca.edu]
    [Home 607.277.7112]
    ------------------------------



  • 9.  RE: William de Blaise wire scale

    Posted 09-25-2018 03:12
    Hello all - I am very glad John Paul's book is becoming a useful reference. I hope, today, to drag my Model 'A' out from under the other Model 'A' - and check for gauge references on the wrest plank. Mine originally had leather plectra, but I cut them off - so many were breaking up - with a pair of centre pin cutters, drilled out the stub in the tongue with a micro drill and, with a specially ground flat file, squared out that hole to accommodate Delrin plectra. Other than that (and changing the operation of the Left pedal to make it work in the conventional manner) I have done nothing but tune and regulate it. I even hired it out to Glyndebourne on one occasion when, during an all Mozart season, they ran out of H'chords for rehearsal purposes.  Michael





  • 10.  RE: William de Blaise wire scale

    Posted 09-25-2018 11:59
    Oh, yes, the '#' on my deBlaise are very white - no yellowing atall atall. Michael UK





  • 11.  RE: William de Blaise wire scale

    Posted 09-25-2018 11:55
    I have unearthed the Model 'A' deBlaise from under the Model 'A' Hamburger S&S, put it on its legs and have taken the gauges of the 8ft Choir. I noted the numerals next to certain wrest pins for the 8ft. As the strings here are readily accessible I have measured the entire 8ft. choir.
    We shall start at the top - No.61 - the F, stamped 00 on the wrest plank. This is a steel 0.008". Though the C# below this has a '0' stamped, in my H'ch. it is still 0.008" The first gauge-change comes at #53 - the A. This is 0.010", stamped 1 1/2.  Next gauge change is at #50, stamped '2'  this is steel 0.011". This gauge goes through to '#36 then changes at #35 (stamped '3') to 0.012". This goes thru' to #27 even though there's a '4' stamped at #31 below the break. Next gauge change is at #26 - F# stamped '5' and is 0.014" gauge for just three strings for at #23 D# it changes to gauge 0.015" stamped'6' This D# and the next D are the last of the 'steels' for at #21 C# it changes to brass, 0.015" stamped '6 1/2'. #20 'C' is stamped '7' and is 0.018" for just three strings. Then at #17 'A' the gauge is 0.020". again just for three strings changing at #14, F# to 0.022" stamped '9'. Next gauge change is #11 D# gauge 0.024" stamped '10'. Next change is #8 C  gauge 0.028 (but stamped #22) then to #4 G# gauge 0.032" stamped 21. The last two notes #2 and #1 are both gauge 0.035" but stamped 20. A load of nonsense unless they're using a totally different set of gauges for the last three gauges - but I fancy they put a '20' where it should read '22' - and vice-versa.
    Whether I can get my micrometer in under the 8' choir to measure the 4' choir is another thing. I haven't tried yet - but it looks very cramped up at the top end!!

    So, if you want me to try please say - otherwise you may be able to extrapolate the 4' from the 8'. Anyway I don't think H'chord strings get any thinner than 0.008". They're probably shorter than the 8' ones which would account for . . .  something.
    Michael from Sunny Sussex-on-Sea in a UK which is currently drifting into the Atlantic - I think . . . . Think BREXIT !





  • 12.  RE: William de Blaise wire scale

    Registered Piano Technician
    Posted 09-26-2018 10:15
    Hi Michael,

    I will be converting to Delrin as well. Here is a YouTube video showing how Carey Beebe does the conversion:

    CBH de Blaise harpsichord delrin conversion
    YouTube remove preview
    CBH de Blaise harpsichord delrin conversion
    Always read the accompanying technical description! More harpsichord stuff @ http://www.hpschd.nu Carey Beebe demonstrating the conversion of the original leather plectra to delrin on a de Blaise harpsichord. The original leather plectrum is seen to be weak and can be broken off. The tongue spring is displaced to allow the tongue to swing back.
    View this on YouTube >


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    [Don] [McKechnie,] [RPT]
    [Piano Technician]
    [dmckech@ithaca.edu]
    [Home 607.277.7112]
    ------------------------------



  • 13.  RE: William de Blaise wire scale

    Registered Piano Technician
    Posted 09-26-2018 10:06
    Thank you so much Michael, above and beyond! I believe I have found an answer via help from Carey Beebe in Australia. According to Carey, the reason for those lower notes going from the 20 stamped on the wrestplank, at the first two, and then up to 22 is what gauge standard was used. Here are his words:

    "The answer is that the bass strings, probably phosphor bronze originally, are measured in standard wire gauge ("SWG"), where the number series goes in reverse, smaller numbers denoting larger diameters. The steel strings are measured in music wire gauge ("MWG"), where the number series reduces in line with the diameter."

    He does not explain how the brass wire was gauged but we can guess that de Blaise used MWG for the brass. My guess now is that at some point after my instrument was built someone replaced the phosphor bronze wire with yellow brass and followed the MWG protocol. It certainly would make sense. On your model A, might those lower strings be phosphor bronze?

    Thank you for offering to measure the diameter on the 4' strings but that is not necessary for my purposes. If you can tell me what the gauge markings are on the wrestplank and, how many notes per each number would be all that I need to compare to mine.

    The gauge markings for the 8' on your instrument are a bit different than mine. Below shows the gauge number, what diameter I measured, number of notes and type of wire:

    00     .008     5 notes     steel
    0       .099     5 notes     steel
    1       .010     9 notes     steel
    2       .011     7 notes     steel
    3       .012     5 notes     steel
    4       .013     3 notes     steel
    5       .014     3 notes     steel
    6       .016     3 notes     steel
    7       .018     1 note       steel
    7       .018     3 notes     brass  (7 is not stamped twice on the wrestplank, it changes from steel to brass within the one 7 marking.)
    8       .020     3 notes     brass
    9       .022     3 notes     brass
    10     .024     3 notes     brass
    11     .026     2 notes     brass
    22     .036     2 notes     brass
    21     .032     2 notes     brass
    20     .028     2 notes     brass

    It is interesting that your instrument has some 1/2 markings and that the .008 steel went through two markings. My model A is quite a bit older than yours so we can guess that they were experimenting with different gauges through the years.

    I did hear from Malcolm Rose and he wondered if those lower strings were "covered." From all I have seen, I do not believe that is the case. I will get back to him with the information I received from Carey.

    Well, I think I would prefer if my little part of the USA would just float into the Atlantic (maybe we could meet up somewhere in the middle!). I'm afraid the USA is sinking into a black hole and into a terribly twisted universe. :-)

    Best,
    Don

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    [Don] [McKechnie,] [RPT]
    [Piano Technician]
    [dmckech@ithaca.edu]
    [Home 607.277.7112]
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  • 14.  RE: William de Blaise wire scale

    Registered Piano Technician
    Posted 09-26-2018 10:18
    It must be due to the material they used at the time my instrument was made. The yellowing sure is ugly but it would cost too much and take too much time to replace what I have. I just will have to sell it as vintage!

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    [Don] [McKechnie,] [RPT]
    [Piano Technician]
    [dmckech@ithaca.edu]
    [Home 607.277.7112]
    ------------------------------



  • 15.  RE: William de Blaise wire scale

    Posted 09-27-2018 03:38
    According to my measurements the strings on the 8 ft. choir are not according to the markings on the wrest plank. Ergo it was either as you suggest - and they were still experimenting - or it has been restrung. I believe the former. There is no difference in colour of the string used - that I can see - of the last three strings from the rest of the brass. My Manual, which bears 'MODEL A - No 632' written on the front cover came with the H'chord complete with various additional annotations for setting the bearings! On page - 9 - the Model "K2" is discussed. That will be the photo on page 180 of John Paul's book - though I also notice there are three pedals on that H'chord but the instructions refer to four pedals. Still in development stage?
    Of course, Whelpdale, Maxwell & Codd were piano makers who made very good pianos for school use under the name 'WELMAR' - this will account for the Very Sturdy construction and the overall weight of this small H'chord. 
    Michael UK - but how United?





  • 16.  RE: William de Blaise wire scale

    Posted 11-20-2018 05:46
    Hello Donald and all - I have viewed the Carey Beebe 'leather plectra conversion to delrin'' with interest - since I did just that on my Wm.deBlaise model A (No. 632) Though I must confess I view the use of a hammer with skeptical alarm - just think of the quensiconces of a miss-aimed hammer!! (Ha-ha!) like the quensicontial part? I used a pair of centre pin cutters, then drilled out the stub with a fine drill and filed it out to fit Delrin plectra with a modified watch-makers fine file. I also modified the 8' pedal to match the normal 'down-for-on' aspect.
    Michael  UK

    ------------------------------
    Michael Gamble
    semi retired
    Brighton
    01273813612
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  • 17.  RE: William de Blaise wire scale

    Registered Piano Technician
    Posted 09-27-2018 10:52
    I wrote to the Robert Morley company to see if they could supply me with any information on the model A string scale. Today I received a reply and I believe we can now confirm that over the years de Blaise experimented with different wire scales. Also, I now believe that the strings were indeed replaced on my instrument at some point after construction. See the attached pdf showing the string scale for a model A that John Morley sent. So far, we have three different string scales for a model A! Mr. Morley also sent a useful comparative table of steel piano wire.

    From all the information that I received, I can now proceed with stringing my model A. I will certainly use phosphor bronze for the first six notes and experiment from there up to note 20 where the change occurs to steel at note 21. I will try both phosphor bronze first at note 7 and up, listen for tonal quality and then perhaps switch out to some yellow brass on a few notes to hear the difference.

    Thank you Michael for your very valuable help in this project!

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    [Don] [McKechnie,] [RPT]
    [Piano Technician]
    [dmckech@ithaca.edu]
    [Home 607.277.7112]
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    Attachment(s)



  • 18.  RE: William de Blaise wire scale

    Posted 11-21-2018 06:45
    I have been 'talking' to Carey Beebe (who is on his way back to Down-Under from Paris) about his YouTube'd method of re-plectra'ing a Wm.deBlaise - and he agrees about the possible quensiconces of using a hammer and that my method is somewhat more controllable.  But - one does at least have a choice!
    Michael   UK





  • 19.  RE: William de Blaise wire scale

    Registered Piano Technician
    Posted 11-21-2018 10:26
    Hi Michael,

    My de Blaise project is on hold while I get to other projects of higher priority. Hopefully I will get back to the plectra replacing within a month.

    I was a bit skeptical about using the hammer method to remove the stub. I found that I could get a hold of the tip of the leather plectra with a small pliers, support the back of the tongue as in Carey's method, and push out the plectra. This worked for most of them and those that did not work I used Carey's method. I was very careful to not damage the tongue.

    One concern I have is the tongue splitting when I snug in the Delrin plectra.  I had only just started setting in the Delrin plectra and have only done a few. Most of those started splitting at the tip of the tongue. I did not put undue pressure on the tongue when setting in the plectra. I believe the tongues are just a bit weak. To remedy this situation I put a drop of thin CA glue on the tip. I believe this will work and will see when I get the project started again.

    Best,
    Don

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    [Don] [McKechnie,] [RPT]
    [Piano Technician]
    [dmckech@ithaca.edu]
    [Home 607.277.7112]
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