Interesting speculation there, Julia. One notable thought is the difference between modern and earlier-centuries perception of this matter of the work marks in the bore. They are very common in Reid instruments which all show an extraordinary degree of craftsmanship. I've just had a look inside an exquisite ivory musette bore, and yes, the point of the drill is very visible. It clearly wasn't thought very important in the 18th and 19th century when instrument design developed as a result of enormous quantities of experimentation and experience in certain families.
Personally, I'd avoid leaving those marks. But I'm grateful to those early makers who did, because it leaves unequivocal evidence of the intended position of those tone-holes, no matter how much they have been altered. In response to your question about unevenness at those drill points and the effect on standing waves, I strongly doubt (and this is just a guess) that it would have any effect on standing waves. Consider that the volume of the cavity caused by a tiny drill point is virtually nothing compared with the volume of the huge cavity that lies immediately opposite; the tone-hole itself. The other thing to consider here is the nature of the cylindrical bore. We expect cylindrical bores to behave in predictable ways because that's what acousticians tell us. To a large extent thats reliable wisdom, but what applies to a clarinet is certainly not true of a small-pipe bore which may be anything from 4mm (very early) to 5+mm (some recent examples). A small pipe-bore cannot function as a theoretical cylindrical bore because of the relatively huge tone-hole cavities. The same is true of a clarinet but the relative disturbance is proportionally much less. It would be nice to think of a well made small-pipe bore as analagous to a long regular and smooth surfaced walking stick. In practice, its effective shape is closer to some knobbly stick pulled out of a hedge. Even if you have sanded it and varnished it afterwards! Even with such an irregular effective bore-profile, it still works best when coated with oil. I wonder what is the best kind of oil to use? Does anyone have any ideas on that? Yours mischievously, Francis On 10 Feb 2011, at 10:38, Julia Say wrote: > On 9 Feb 2011, Philip Gruar wrote: > >> I'll just say that with care, a flat-ended drill and delicacy >> of touch, there should be no need for rods down the bore. You just stop the >> drill before it goes too deep! > > Well, quite. One can both hear and feel the drill reaching the bore. > Nevertheless > it was something I was warned about, and was checked up on. > > Now I'm wondering about the acoustic effect of all those "dimples" that do > occur in > various makes of pipes (historical and otherwise) on what I believe is > supposed to > be a smooth shiny bore. > (Not to mention all the "agricultural" standard bores that are about - this a > phrase which makers fettlers sometimes use!) > > My ivory chanter is jointed near the low E and when I got it, squeaked on > that key > at the least provocation. Adrian had a look at it and suggested there was > possible > unevenness in the jointing. We had a bit of a go at sorting it and the matter > improved (so did my playing, which probably helped too). > > The point being that I'm wondering whether the uneveness caused by drill > marks in > the bore would be sufficient in some cases to upset or affect the standing > waves > and therefore tuning / tone / stability / reed / whatever. > > Since that's physics, which frightens me rigid due to some very poor teaching > in my > yoof, I'm going to tiptoe away now and let the heavy duty theorists get to > work on > the suggestion. > > Julia > > > > To get on or off this list see list information at > http://www.cs.dartmouth.edu/~wbc/lute-admin/index.html
