Moving the Cork back

[Jon C.]

I have found that Pratten models like to have the cork about 21mm, where Rudall's like about 19mm. I usually set the cork position by checking the first and second octave of A and B notes.

[an seanduine]

Hmmm.My maker seems to have retired, or died, or something, since he is no longer on the 'net and does not respond to emails, so I cannot consult him.
However, since someone did the hard part before I acquired this flute, the cork is in a very sweet spot. . .octaves are in tune and strong toned, as well as easily shifting from octave to octave. I measure this cork at 20 mm in a lined head of 18.1 mm dia.
According to the cached website on the 'Wayback Machine, this flute started out based on a Prowse flute with some modernisation.

Cheers,
Bob

[Kirk B]

used ta be that once you'd removed the cork ya might as well finish the bottle

Yarp. Once I pull the cork, it goes right into the trash.

[Gabriel]

I use an old Korg Tuner. Also my ear.
...

Thanks for that, Casey. Of course what we hear and what electronic gadgets measure are two different things. I usually use the tuner to determine a starting point for tuning (usually the two or three finger note in the 1st register) and go on by ear then. I was fine tuning my newest F flute the other day and noticed that a newly tried-out hole position (RH1) was wrong, the second octave was sharp. So I checked against the tuner and it showed 20-22 cent. That's why your message took me aback a bit. I think that this is not too bad, a good embouchure will easily blow the upper register in tune (and casually forces the player to learn that the second register needs less air than the first!), but for my very ears, the 20 cents, without special embouchure attention, clearly were sharp.

I solved the problem with a bit of wax northside and undercutting southside and will bore the hole a bit further down the tube next time. The second octave is reasonably well tuned now, xxxooo and xxoooo being still a bit sharp (about 5-10 cents), but that works for me.

[sponge]

Thanks to all,

quite a lot more info on this subject than I expected, I was thinking it would be a straight no dont do it.

so thanks again

sponge

[MarkP]

well I don't have the knowledge to explain the acoustics of it but, unless my ears are playing tricks, Jon's rough guide of 19mm radically improves the lower end on my Metzler(?) 8 key. I've been working on my embouchre to find more power in the weak low D the past few days. Just tried pulling the cork out to 19mm and now I can cran it. Interesting! Maybe it's psychological? It's a lot further out than the screw adjustment would suggest, just about as far as it will go (although perhaps the cork is too long).

Guess it won't work for all, but a good tip nonetheless

[jemtheflute]

Mark, Chris Wilkes recommends about 21-22mm back from embouchure centre, which enriches the low register (at some expense to the ease and clarity of the 3rd, but as we mostly don't go there.....) It doesn't make too much of a difference to the octave tuning either, which is the primary purpose of the adjustable stopper. I suspect I'd have set he stopper in that "nach Metzler" ( ) of yours to about the rule of thumb 19mm when we worked on it together last summer....

[Doug_Tipple]

used ta be that once you'd removed the cork ya might as well finish the bottle

Yarp. Once I pull the cork, it goes right into the trash.

I agree with Denny on this on, however, tonight is a no alcohol night while I try to get over the flu. I don't agree with Kirk about throwing away wine corks. Of course, they can be used for flute stoppers, but if you drink enough bottles of the stuff, you can begin to think about about making end tables or maybe a whole acoustic wall in your studio. Saving wine corks is a whole lot more satisfying than collecting used beer cans. At a four to one ratio of beer cans or bottles to wine bottles/corks, based on the alcohol content alone, my accumulation of wine corks and empties isn't quite so frightening.

[crookedtune]

A great read: http://www.corkboat.com/

[Aanvil]

I've been saving the bottles for recycling and its been a sobering experience.

Actually no... it hasn't.

[Nanohedron]

...however, tonight is a no alcohol night while I try to get over the flu.

You DO realise there's an argument to be made for that being an act of immoderation in itself, don't you?

No alcohol. My lands. Alcohol is an antiseptic.

[Maihcol]

If the people throwing away wine corks could throw them far enough and in the right direction, they might land here...and I could be putting them into flutes ...I seem to be only able to find conical corks here – have to reshape them at the same time as sanding them down! Still much quicker than the delrin stoppers with rubber O-ring...

I set them at 20mm back in the conical flutes and 17mm in the Boehm type . There seems to be more discussion of the cork position in the conical flute than in the Boehm – likely due to the much more frequent need for the 3rd octave in the latter which doesn’t leave much option. I’d say cork position in the conicals could be another of those player dependent issues, like the preference for a long or a short foot for example.

Garry

[Doug_Tipple]

Garry, you can buy used wine corks on ebay, bags of 'em, more than you will ever need. However, unless you are lucky it is hard to find corks that are the perfect diameter for the bores of the flutes that you are making. I have some rasp-type files that I use to remove cork to size the cork for the flute bore. Sanding paddles are used for final sanding of the corks. By the way, one good wine cork will make three flute stoppers with a half inch thickness, so unless you make a lot of flutes, you don't need many corks. My own cork to flute ratio is growing every day based on my own consumption of wine for dinner.

[Maihcol]

...And you'd think conical corks would be good for conical flutes!...
They're not actually a problem to sand down though. I have a little jig which I use to hold them between centres on the lathe and then it's just a matter of sanding them down with a strip of sandpaper – and knowing when to stop before they get too small! I have a few of those around...I've been mostly using the delrin stopper with rubber O-ring though.

Garry

[pflipp]

My personal advise is to keep away from wine corks and stick to champaign and special beer corks. They don't contain an opener hole, since you pop them, and if you make your own flutes, their basic shape can provide a classy crown on an otherwise blatantly cheap stick of PVC. I don't finish my flutes as nicely as Doug does, so it helps a lot if the crown tells you that the makers are called "Moet & Chandon" or -ever so applicable- "Piper Heidsieck".

(A little word of warning: if you use a cork freshly off of a Kriekenbeer, expect it to smell nasty at first, and to shrink more later. It can mask bad flute odour, but only by means of another bad odour.)