<HTML> <HEAD> <TITLE>Re: [CAUT] Harpsichord questions (long)</TITLE> </HEAD> <BODY> Comments (answers) interspersed below: On 4/17/05 2:41 PM, "David Vanderhoofven" <david@vanderpiano.c= om> wrote: <BLOCKQUOTE>Easing the keys seems rather crude.=  The key pins are much smaller diameter than in a piano.  There i= s a mortice for the key pin to move forward and back in, but there are no ke= ybushings.  The front key pin is located at approximately the balance p= oint of the key, and the back key pin is located close to where the capstan = would go in a piano key.  With the keys and keyframe out, we played eac= h key a few times to find the sluggish keys.  When we found a sluggish = key, we took the key off the keyframe and inserted a spare key pin into the = mortice and moved it back and forth until the key was no longer sluggish. <B= R> I suggested to the professor about polishing the keypins and lubricating th= e keypins, and he was hesitant, wondering if the polish or lubricant would c= ontaminate the keys.  I was thinking of using Flitz or Simichrome polis= h and the cleaning the key pins well, then applying McLube or a teflon spray= to the key pins.  Or perhaps applying a little bit of micro-fine teflo= n powder on the keypins?   Question #1. Have any of you noticed any ill effects from polishing/lubr= icating harpsichord keypins?  Is any lubrication necessary or ev= en helpful on harpsichord keypins? </BLOCKQUOTE>Haven’t had any ill effe= cts, nor would I expect any. I doubt polishing and lubing will cure all the = sluggishness problems, but it will at least prevent squeaking (which does ar= ise sometimes). <BLOCKQUOTE> Question #2.  How can you tell if the key pin is tight at the t= op or the bottom of the key? </BLOCKQUOTE>You’ve hit on the basic = problem of easing harpsichord keys. The mortise is parallel to and in contac= t with the pin from hole to the top. It is very difficult to tell where the = friction is. My best advice is to use a jeweler’s file – the one= with parallel cutting surfaces that comes to a point – to clean out a= ny loose wood fibers within the mortise. Usually that is the problem. Take c= are not to make the mortise “tapered” (keep it parallel to the p= in, and don’t over-ease). A wee bit at a time. Try to make most of the= pressure on the file “at the point” - IOW picture yourself cutt= ing away wood below the top of the mortise, not touching the top of the mort= ise or enlarging the BR hole.     The mortise is typically created by drilling one ho= le all the way through (creating the balance hole), with a couple other hole= s drilled on either side but not all the way through the key. Then a metal p= unch of appropriate shape and dimension is hammered into the hole to create = the requisite shape. Leaving plenty of residue to cause problems.     Another useful “easing” tool is the cor= rect sized drill bit (preferably selected from a set of 1 – 60 numbere= d bits, but you might find the right size in metric or SAE) - it needs to be= just a couple thousandths larger than the pin. Use it in a pin vise, turnin= g it while angling it back and forth within the mortise - carefully.     Bottom line: mortises must fit the pins very closel= y, but be free. Very troublesome design. Use care when easing. Keys should h= ave minimum lead in them for return (leads are almost always on the back sid= e), and the key should just float to rest position. That’s the ideal &= #8211; you may find you have “over-leaded” keys. But it is easie= r to determine if the key is eased “perfectly” on a harpsichord = than on a grand piano (that’s the “good” news <g>).<= BR> <BLOCKQUOTE> Question #3.  Can I use regular paper and card punchings to level k= eys in a harpsichord, or do I need to buy some special smaller punchings for= this purpose? </BLOCKQUOTE>Paper and card punchings for p= iano work just fine. <BLOCKQUOTE> Question #4.  Is it possible to do fine adjustment of key dip on a = harpsichord, and how is this done?  Or should I even worry about this o= n a harpsichord? </BLOCKQUOTE>Harpsichord key dip should be = reasonably/roughly even, but it isn’t the issue it is with a grand pia= no. Some have the upstop rail you describe. Others rely on the jack hitting = the jack rail – in which case one trims the top of the jack to arrive = at the appropriate dip. In general, if it works, leave it alone. <BLOCKQUOTE> The harpsichord will be used as part of the continuo for the Vivaldi Co= ncerto in C major for Two Trumpets & Orchestra, R. 537. Question #5.  What would be an appropriate temperament to use for a= harpsichord with this music? </BLOCKQUOTE>Mr. Young’s temperament = is my favorite generic well-temperament for baroque. Valotti or Valotti/Youn= g are a couple other reasonable choices. But you might actually be best with= old vanilla ET depending on the orchestra. In the final analysis, it is unl= ikely anyone (except possibly the harpsichordist) will notice. <BLOCKQUOTE>Thank you all for this wonderful li= st and your help! David Vanderhoofven </BLOCKQUOTE>Regards, Fred Sturm University of New Mexico </BODY> </HTML>