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Parchment Hinges

  • 1.  Parchment Hinges

    Posted 07-07-2018 10:18
    I was called in to look at this 1830's Brown action, brought into a cabinet maker's shop for case refinishing. The boss had successfully extracted the action and covered it with a sheet on a separate workbench, but person next removing the sheet snagged these hammers in the process.

    They want me to do the repair. They're certain they can clean out the parchment in the shank with a jeweler's saw. It looks to me that I'll have to splice on a section of parchment to replace that remaining under the wood cover on the rain and I can do an individual strip for each shank (saving me the trouble of assembling the three shanks on a single piece of parchment, "old school").

    Anyone have experience with parchment hinges?
    Any time-honored procedure (or other wisdom)?
    Where do I get the genuine parchment?



    TIA

    Bill Ballard

    ------------------------------
    William Ballard RPT
    WBPS
    Saxtons River VT
    802-869-9107

    "Our lives contain a thousand springs
    and dies if one be gone
    Strange that a harp of a thousand strings
    should keep in tune so long."
    ...........Dr. Watts, "The Continental Harmony,1774
    +++++++++++++++++++++
    ------------------------------


  • 2.  RE: Parchment Hinges

    Posted 07-07-2018 10:34
    That would be vellum. I think Jurgen has some or access to some. Will the cover lift without damaging other hinges? Try that first to see hoo much vellum you'll need. Get extra because they are going to break more. They are very fragile at this age.

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

    Jon Page
    ------------------------------



  • 3.  RE: Parchment Hinges

    Posted 07-07-2018 11:24
    I'll see the piano again on MON, and can find out what's going on under the cover. I was assuming that under the cover, the vellum was glued to the rail below it. This would rule out scavenging parchment from here.
    Will the cover lift without damaging other hinges? Try that first to see hoo much vellum you'll need.
    Jon Page,  07-07-2018 10:33


    ------------------------------
    William Ballard RPT
    WBPS
    Saxtons River VT
    802-869-9107

    "Our lives contain a thousand springs
    and dies if one be gone
    Strange that a harp of a thousand strings
    should keep in tune so long."
    ...........Dr. Watts, "The Continental Harmony,1774
    +++++++++++++++++++++
    ------------------------------



  • 4.  RE: Parchment Hinges

    Posted 07-07-2018 10:40
    It's been quite a while but I used to get parchment from http://www.talasonline.com/ along with a good PVA glue called Jade. It may have a grain and tear easier in one direction than the other so play with a sample. The key was not to get the parchment moist as it quickly became soft. Put glue in the slot, slide the hinge in and remove squeeze out at the joint that will interfere with motion. I'm sure others have better and more recent ideas..


    ---Dave 

    Sent from my phone, forgive typos! 





  • 5.  RE: Parchment Hinges

    Posted 07-07-2018 12:20
    John Delacour's website has a fine, detailed article on parchment hinge repair.
    It's worth seeing how a specialist makes these repairs.
    http://pianomaker.co.uk/technical/vellum_hinges/

    ------------------------------
    Ed Sutton
    ed440@me.com
    (980) 254-7413
    ------------------------------



  • 6.  RE: Parchment Hinges

    Posted 07-07-2018 13:36
    If you're not an "originalist" i found an alternative material that is far superior, and more importantly, easy to get. The used 1" wide belts off of a belt sander make excellent hinges. 





  • 7.  RE: Parchment Hinges

    Posted 07-08-2018 01:58
    Parchment and vellum are two forms of fine prepared calf or goat hide.  Be very certain that you do not get any material that isn't actual hide.
    Considering that this vellum has lasted for well over 100 years there has been nothing that has been tested or performed as well.

    Vellum is tough enough that you probably cannot tear it with your bare hands.

    Antique book binders can sell you a "grab bag" of parchment or vellum scraps inexpensively, you can find them on-line.

    Vellum is easily cut to size with scissors and can be glued with any adequate glue (hot hide glue is my preference).  You can clear out the slots with a fine jewelers saw.

    ------------------------------
    Blaine Hebert
    Duarte CA
    626-795-5170
    ------------------------------



  • 8.  RE: Parchment Hinges

    Posted 07-08-2018 14:29
    I've found a good substitute to be the glue-imprenated linen strips the supply houses sell for replacing ivory keytops in the original fashion.  This is the traditional work-around and you may already have some to hand.

    What makes me wary of using vellum is not only the scramble to find some of the appropriate thickness, but also questions about how it has been prepared and the general consistency.  Attempts to use it left me rather unsatisfied--it was a little too flexible.  Leather, like felt, is quite variable in its properties not only due to the skin you start with but also to exactly how it's prepared.   You want a hammer flange to be as flexible as possible in the back and forth direction, and as stiff as possible in the side-to-side direction.  And I couldn't find anything else that didn't allow for excessive wiggle in the side to side direction.

    ------------------------------
    Cecil Snyder
    Torrance CA
    310-542-7108
    ------------------------------



  • 9.  RE: Parchment Hinges

    Posted 07-08-2018 14:50
    The sanding belts I use as hinge material is .014" thin. Zero side play, will never wear out. It's so strong I bet I could pull a car with it. Ive used it on many squares.
    -chris





  • 10.  RE: Parchment Hinges

    Posted 07-08-2018 14:51
      |   view attached
    The sanding belts I use as hinge material is .025" thin. Zero side play, will never wear out. It's so strong I bet I could pull a car with it. Ive used it on many squares.





  • 11.  RE: Parchment Hinges

    Posted 07-09-2018 15:35
    There is no decent replacement or alternative to vellum.
    For this simple reason: materials such as leather (tanned), linen, plastics etc will do two undesirable things:
    1) they will stretch
    2) they bend in more than one plane at a time

    This means that they do not act as a correct hinge which moves only in one, controlled plane. The result is that the hinged part ( hammer shank, damper underlever, pall, etc) will wobble and have side to side play. Hammers will never strike the strings in the same place twice, causing tonal and voicing problems.

    The old guys stumbled onto an amazing solution when they used vellum.  Anyone working on a piano that incorporates this type of hinge should acquaint themselves with the use of vellum. The link Ed gives is very useful.

    Vellum is readily available, here:
    Vintage Piano Vellum & Leather
    Pianofortesupply remove preview
    Vintage Piano Vellum & Leather
    Special leather for restoring vintage piano actions. Vellum was used successfully as hinges for action flanges. Our vellum comes in two thicknesses, we recommend the 0.3 mm variety for Viennese piano actions and for restoring Bluthner grand piano damper underlevers. Vellum is sold in strips 2″ x 32″.
    View this on Pianofortesupply >



    ------------------------------
    Jurgen Goering
    ------------------------------



  • 12.  RE: Parchment Hinges

    Posted 07-09-2018 16:25
    Wrong. If that ideology were even remotely true, harpsichords would still just be using crow quill and boar bristle. Now they use celon, delrin, and brass wire. What about hammershank knuckles? Only use real leather? Or is synthetic OK? What about carbon fiber action parts? The point is new materials are sought after if they work better, the cost is reasonable, and they are accessible. 
    The belts I mentioned, I've been using for years, and if you have a 1" sander they're free as hinges.





  • 13.  RE: Parchment Hinges

    Posted 07-09-2018 21:20
    I don't recall mentioning harpsichords or brass wire, or implying that all old materials are preferable to new ones in all cases.  Please don't put words in other people's posts or run astray with your extrapolations.

    There are many good reasons to stick to original materials when restoring a vintage instrument. That discussion is over and done with and we know the outcome.  In case anyone forgot, the consensus is to not put plastic in a 1780s harpsichord.

    Vellum is an excellent material, and in this case, had it not suffered abuse and ended up being forcefully torn, this 180  year old (!!!) material would still be in working order. That should speak for itself.

    Thankfully, for this particular repair, the original material is accessible, economical, works better and will last longer. Case closed.

    ------------------------------
    Jurgen Goering
    ------------------------------



  • 14.  RE: Parchment Hinges

    Posted 07-09-2018 22:23
    Jurgen,
    I don't recall mentioning harpsichords or brass wire,
    You didn't . It's a device in writing called using an example to prove a point.

    or implying that all old materials are preferable to new ones in all cases.  Please don't put words in other people's posts

    I didn't. Those are your words.


    or run astray with your extrapolations.
    I made no assumptions then, but i'm beginning to now.
    -chris





    ------------------------------
    45 2020

    chernobieffpiano.com
    865-986-7720
    ------------------------------



  • 15.  RE: Parchment Hinges

    Posted 07-10-2018 08:25
    Crow quill is very easy to work with if you know what your doing.   The only reason the modern plastics are used is because they are more convenient.  Fine harpsichords often have crow.  Plastic jacks are cheaper than wood,  but wooden jacks do sound better,  as they absorb noise rather than reflect it. 
    Vellum isn't difficult to find,  so why wouldn't one use what was there?





  • 16.  RE: Parchment Hinges

    Posted 07-10-2018 10:46
    Douglas said,
    ".........but wooden jacks do sound better,  as they absorb noise rather than reflect it."

    Interesting!  Certainly different plectra have different tonal qualities, but I wasn't aware that a harpsichord jack had any acoustical function. Could you go into more detail of how that works? Perhaps there is a study you could refer to?
    If a jack has a piece of lead in it, does it absorb even more noise?
    What if i replace some plastic jacks with a couple wood ones in my harpsichord, would there be a difference in a blind test Douglas?

    Thanks,
    -chris

    ------------------------------
    45 2020

    chernobieffpiano.com
    865-986-7720
    ------------------------------



  • 17.  RE: Parchment Hinges

    Posted 07-10-2018 11:06
    Chris,
    Every single thing that is put into the making of anything causes a difference, no matter who perceives it. Often it is the extremely small things that add up to make something unique and special.

    ------------------------------
    Jason Leininger
    Pittsburgh PA
    412-874-6992
    ------------------------------



  • 18.  RE: Parchment Hinges

    Posted 07-10-2018 07:19
    Jurgen, is the vellum you carry made of calf skin, some other type of leather, or is it made of cotton and wood pulp?

    ------------------------------
    Mario Igrec, RPT
    http://www.pianosinsideout.com
    ------------------------------



  • 19.  RE: Parchment Hinges

    Posted 07-10-2018 08:18

    ......Mario,  this from Jurgens's site   Viennese beak leather is used on Viennese shanks. Our beak leather is carefully selected from specially tanned skins of the Chamois, an alpine mountain goat. Sold in 10 x 10 cm = 4 x 4″ pieces, enough for one set of Viennese shanks.

    • A. #370103 Vellum for vintage action flanges, 0.3 mm thick
    • B. #370107 Vellum for vintage action flanges, 0.7 mm thick
    • C. #370210 Beak Leather for Viennese actions


    ------------------------------
    Martin Snow
    Boston MA
    617-543-1030
    ------------------------------



  • 20.  RE: Parchment Hinges

    Posted 07-10-2018 10:46
    The majoitory of leather on the market...if not all that is available is inferior to what was originally used in older instruments. It is the same sort of dilema that is found with felt.  The way the skins are processed and selected is different from traditional methods. The chamois available today feels like a sponge compared to the resilient, bouncy, yet incredibly soft leather found on early piano hammers.  If this wasn't so, restorers and builders would not still be looking for an equal replacement. As for the use of sandpaper for hinges in 200 year old pianos........if I find them I will be sure to replace them with vellum.

    ------------------------------
    Jason Leininger
    Pittsburgh PA
    412-874-6992
    ------------------------------



  • 21.  RE: Parchment Hinges

    Posted 07-10-2018 11:29
    Jason,
    It's not sandpaper that I use, it's the backing. With such a small surface that is showing, I really don't think anyone could tell the difference, or care as long as it's working. Probably be replacing the old vellum that failed instead.
    BTW, i wasn't presenting an either or as the discussion morphed into.
    It's just an alternative that I found that works extemely well for its intended purpose. I'm not trying to sell anything here.
    -chris





  • 22.  RE: Parchment Hinges

    Posted 07-10-2018 13:26
    Chris,
    Fair enough.  Everybody has different preferences for solving these issues.

    ------------------------------
    Jason Leininger
    Pittsburgh PA
    412-874-6992
    ------------------------------



  • 23.  RE: Parchment Hinges

    Posted 07-10-2018 17:31
    Mario,
     The vellum I carry is calf skin.  There is a type of translucent tracing paper also known "vellum", but only because it looks a bit similar. The two should never be confused. Never use the drafting store "vellum" in a piano action.

    Martin, the quote from my website could be confusing for some, as it refers to beak leather, not vellum.  Beak leather is an entirely different product than vellum. It has different characteristics, and is used for a completely different application. It does not apply to this discussion at all.

    ------------------------------
    Jurgen Goering
    ------------------------------



  • 24.  RE: Parchment Hinges

    Posted 07-11-2018 14:56
    Thanks Jurgen. Good to know.

    ------------------------------
    Mario Igrec, RPT
    http://www.pianosinsideout.com
    ------------------------------



  • 25.  RE: Parchment Hinges

    Posted 07-10-2018 11:18
    ​Bill,
    I am very interested in this action.  I have only seen it in patent drawings. Does it have wooden or wire jack tenders? It would be great to see more pictures.

    I only managed to show it to Gene Roe, but I have a fully restored 1890 Brown action ready to go back into that 105B whose soundboard was getting thumped when you and the NH chapter came for a visit.  I think that the one I restored is amongst the last and represents the final form.  Yours must be amongst the first.  I'm guessing that it comes from a Chickering?

    About the vellum hinges:
    As a martyr-level "originalist", I have to agree with Jurgen.  The unnecessary interpolation of crude modern materials into a piano of this age, when a proper replacement is readily available, does an injustice to the instrument; adhesives included.

    I have only had one experience working with vellum hinges, and that was in a Bluthner damper action from 1872.  I was daunted at first, but it soon became clear that the material was actually easy to work with.  For all the fancy qualities of vellum and its exotic sources, it is, in the end, a bit of rawhide.  Like a dog's chew toy, the vellum is firm when dry, but let it get wet, an it turns back into a soft, stretchy bit of skin.  For this reason I would not try to cut the vellum out with a jeweler's saw.  The wood will be softer than the glue-hardened vellum, and the saw will wander and destroy your kerf.  The better, but slower, way is to just wet the edge of the exposed vellum.  It will resist absorption at first, but everything involved likes water and the vellum will start wicking.  I would not dip the parts, just keep wetting the edge of the vellum.  It will take a little time, but you will be able to eventually grab a corner and pull the vellum from the kerf in one piece.  This leaves a beautiful straight slot; and so the action geometry will be unaffected.
    On the rail, I would do the same thing, but work my way in from the end. The last piece of vellum I would not wet past its midpoint. Even if that one takes extra long, it is crucial that the vellum for the fourth note stay absolutely dry, or you will be replacing that one too.

    Be well,
    Craig





    ------------------------------
    [Craig] [Hair]
    [Hampshire Piano]
    [Conservative Restorations]
    [Chesterfield] [MA]
    [413-296-4205]
    [hampshirepiano@gmail.com]
    ------------------------------



  • 26.  RE: Parchment Hinges

    Posted 07-10-2018 21:57
    More important is the leather covering on these actions. Avoid leather from the piano supply houses and avoid synthetic leather. Avoid suede.
    I didn't try goat though because I hate goat cheese. But i'll tell you that deer leather is fantastic for these actions. It has a softer and finer grain than anything else i found. The softer deer leather really helped with the tone. I'm pretty convinced that deer was originally used too. Deer hide is cheap. And it's free if you know how to tan a hide and have a neighbor that likes to hunt like my neighbor.

    ------------------------------
    45 2020

    chernobieffpiano.com
    865-986-7720
    ------------------------------



  • 27.  RE: Parchment Hinges

    Posted 07-11-2018 23:19
    Chris,
    You had me convinced to try out deer skin leather, but then I realized, "shoot! I hate deer cheese!"

    Joe Wiencek