Gordon- Perhaps most important is to be aware that too great an angle will cause the string to wind down the pin on its own, making it impossible to get tight coils. Check the Pianotech archives about this. Newton Hunt made some good posts on the topic. Your laser approach would probably work best if you arranged it to point to the bridge pins of the note you're drilling (assuming the block is in the piano. I think most small shops have adopted some form of the small floating press to drill in the piano. See the article by Jack Krefting in the PTG Reprints book. Ed Sutton -----Original Message----- >From: gordon stelter <lclgcnp at yahoo.com> >Sent: Oct 13, 2006 1:05 PM >To: Pianotech List <pianotech at ptg.org> >Subject: Laser line for block drilling ? ( Was: Benefits of tilting the piano, instead of the drill press . ) > > If the drill bit is pointed directly toward earth's >center, and whatever the press is sitting on is flat, >and level, the pin holes will all be drilled at >exactly the same angle, regardless of which way the >body of the press is turned, as it is moved from hole >to hole. That is very enticing. > If the far end of the piano is put a little lower >than the block end, for example, and the block is >level to the floor from side to side, the pins in >their newly drilled holes will all lean directly >toward the stretcer ( or top, in an upright ) at >exactly the same amount. Regardless of whether the >drill press was rotated inadvertently, as it was slid >along from side to side. > Not so if the bit itself is angled, and the piano >is level. > Because this uniformity is so appealing, it is >why I asked if, in actual practice, pianos are built >this way? ( With the pins leaning toward the >stretcher, but perpendicular in all other planes ). > > Or, instead, do the pins always lean directly >away from the string line, regardless of their >orientation to the stretcher ? I have a 1923 Steinway >"M" I'm working on. The plate is out and the block >still in it, so I'll put some appropriately sized >dowells in the holes, and see which it is, in this >particular case. Directly toward the stretcher, or >toward the stretcher, but modified to keep them in >line with the stings? > Of course, one could keep a whole section drilled >the same in relation to the string line, such as in >the bass section where they're all basicaly parallel, >but at an angle to the piano's sides, by jacking up >one side of the piano, as well as letting the tail >down, before drilling. But if one wanted all the pins >to be exactly in-line with the strings, such as in a >"fanned out" section, a line drawn through your marks >on the block, and some means of registering the >already-tilted drill press to that line, while slid >along the plank on top of the piano, would ensure >this. That is what I was referring to. Perhaps a rod >secured to the drill press base, with a couple of >small rods hanging staight down from it. Better yet: >one of those laser-lines now used on many saws and >measuring markers. If the laser line was kept directly >along the 3 drilling marks made on the new block for >each unison, as the press was slid fore and aft, each >hole for that unison would be at exactly the same >anglre, and directly away from the string line, >without leaning from side to side. > Peace, > G > >--- Farrell <mfarrel2 at tampabay.rr.com> wrote: > >> Let me see if I understand you correctly. Let's >> start with tuning pins in >> the high treble section of a grand. The strings run >> roughly perpendicular to >> the stretcher. So the tuning pins will likely have >> some lean toward the >> front of the piano (keeping the pin close to >> perpendicular to the string) - >> and the angle of that lean will form a plane that is >> perpendicular to the >> plane of the stretcher. >> >> Now, if I understand you correctly, your question >> arises in areas like the >> low tenor, where the strings angle off toward the >> bass side of the piano and >> form an acute angle with the plane of the stretcher. >> I keep the plane of the >> tuning pin lean one the string line - so that the >> pin will lean mostly >> toward the stretcher, but a bit toward the treble. >> >> I just eyeball it as I drill. I look to see where >> the string would go and >> line up my drill to follow the string line as I >> stated above. I will do a >> half dozen notes or so and then reevaluate and >> change the angle a tiny bit >> if needed. >> >> I really don't understand what you are talking about >> with tilting the piano >> and putting it on it side. Whatever. Just keep the >> pin lean on the string >> line and lean the pin back so as to keep it >> perpendicular to that last >> little length of string as it runs over the plate >> toward the tuning pin. >> Actually, I usually lean the pin back a degree or so >> from that, figuring >> that it may just lean forward a tiny bit on its own >> - or at least it will >> tend to keep the coil nice and tight. >> >> Is that what you were asking about? >> >> Terry Farrell >> >> ----- Original Message ----- >> > If you tilt the drill press, and slide the >> press >> > across the piano on a plank, and keep the drill >> press >> > base, and arm, perpendicular to the stretcher, the >> > pins will all lean directly toward the stretcher. >> If, >> > on the other hand, you make sure the arm/head of >> the >> > drill press is perfectly lined up with the string, >> the >> > pin hole will be directly angled away (7 degrees >> or so >> > ) from the string. There's a difference. I am >> > wondering what manufacturers used which. By >> tilting >> > the drill press in this fashion, though, you are >> > risking having the pins angled this way or that, >> if >> > you roatate the press base, at all. Indexing lines >> > woulds keep your intended results uniform. >> > By placing the drill press on the floor, or >> > overhead, and tilting the piano, you eliminate >> this >> > discrepancy. As long as the bit is "plumb" to the >> > floor, all the angles will be the same, regardless >> of >> > how the base is rotated. >> > Peace, >> > G >> >> >> > > >__________________________________________________ >Do You Yahoo!? >Tired of spam? Yahoo! Mail has the best spam protection around >http://mail.yahoo.com
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