I just took a try at making a tuning wedge for a homemade pvc flute. The flute was made
according to the instructions on Doug Tipple’s Website.
After making the flute, I cut a piece of 3/4" schedule 40 pvc pipe length-wise in half, 10cm
long. I put tape on one end and marked a spot on the tape 4mm up from
the inside surface. I lifted the opposite end up with pieces of paper
to get the correct height. I sprayed the surface with a mold release; poured
in an epoxy mold mix; waited 24 hours and removed the piece. With the
stopper one bore length from the embouchure center, I slid in the
wedge. Octaves one and two were in much better tune than before. Tone
was initially weak but moving the wedge 90 degrees toward the mouth
side greatly improved the tone. The pitch of all notes was around 20
centers flatter than before, though in tune with each other. I guess I
would need to adjust up all holes to fix this, or make the embouchure
larger.
Way to go! You’re right about the tuning effects. FWIW, I’d say it is easier to make a wedge from a piece of the same tube or a slightly smaller guage. After cutting to roughly the right dimensions it can be molded to shape by using a segment of the main tube for a mold as you did, heating the wedge piece to malleability with a hot air gun and pressing it into the mold with a piece of suitably sized dowel until it cools and hardens to its new shape; then you can file/sand it to final shape/correct size.
Dan, I tried to make a wedge by using the same moulding technique, only I used Portland cement, following Jack’s suggestions. I’m sure that your epoxy wedges worked much better than mind, which broke to pieces when tried to get them out of the mold.
I would listen to Jem’s good advice about using a hot air gun. PVC, when heated, will become somewhat pliable and can be shaped. You can even expand thin-wall pipe to make tuning slides, as some makers do. Check out digeridoos online to see the limits of shaping pvc with heat.
I’ve now tried some heat gun experiments. I heated and stretched some sdr 21 3/4" pipe over a schedule 40 3/4" flute to make a lip plate. To make a joint, rather than stretch another piece over the two flute parts, I stretched the two sch 40 flute parts over a short piece of 3/4" copper pipe. The copper pipe has the same interior diameter as the sch 40 and is thin enough to minimize the area change with tuning. Here’s a picture: http://www.danmozell.com/flute.jpg.
The tuning wedge I previously made for a straight one piece flute worked almost perfectly with that flute. When I put the same wedge in this new two piece flute with the lip plate, the second octave actually sharpens too much (at least with my beginning technique). Can anyone explain why the effect would be different in the two flutes? How should I modify the wedge to sharpen less; make it shorter?; decrease the thickness along the whole length? Thanks.
Looking good, Dan. I’m not sure about the wedge effect you describe - there are so many variables. I do know that making the embouchure chimney deeper affects the tuning, as does embouchure size, requiring a different distance from embouchure to 1st tone-hole and possibly requiring resizing/placing of all the tone-holes; so it could be those effects rather than the wedge you are noticing. However, reducing the size of the wedge would be my first experiment - as the other factors are now fixed and you can easily make another wedge if you screw this one up! However, since it is good with the first flute, I’d leave it intact as is with that and start over - copy it and then reduce (I’d say reduce the whole wedge proportionately) by gradual amounts and keep testing.
FWIW, my experience with my school piccolos with the kids making rather crude wedges and by no means uniform in size/profile, was that moderate variations in wedge shape made little difference but the scale length correction for with or without wedge was crucial, especially in a one-piece, non-tunable body. If you have a tuning slide, that problem is reduced.
On balance, though, over-sharpening of the 2nd 8ve does suggest too big a wedge for the particular design.
I made a smaller wedge, this time using a piece of pvc and the heat method. It worked well. I’m also experimenting with wedges for pvc tin whistles. I guess people don’t usual bother with this on cylindrical whistles since you can blow the second octave into tune, but I’m curious.
I tried using the heat method for making a joint for a cpvc whistle. The cpvc doesn’t react the same as pvc. The surface bubbles up. I may have to go back to acetone for expanding cpvc.
Dan, I’d be interested in seeing an RTTA plot with and without wedge if you get a chance. I’ve been meaning to do this for some years, but never find time!
If you haven’t tried RTTA, give it a go - it saves heaps of time when doing development work like this and gives you much more precise data, in an easily stored form. I use Flutini for first analysis and to guide tweaking, then export the data to the Polygraph and then on to my own Excel spreadsheets when I want more detailed analyses and comparisons. If you haven’t seen it, check out http://www.mcgee-flutes.com/RTTA.htm
Mac users please note that Dan Gordon (Australian flute maker and player) has now ported Flutini to the Mac, follow the above link for download.
Or if you prefer Dan, email me an .mp3 of with and without wedge and I’ll do the RTTA.
Interesting idea! But as a beginning player, a plot of me playing won’t be very meaningful. I might get around to it anyway, but I’m so busy I have to squeeze in time here and there. I had a recent surge of time because I was sick for a week. Now I’m back to my non-musical hectic job. Anyway, what’s the point of comparison since it’s possible to lip the high notes into tune without the wedge? Wouldn’t you just be measuring the players skill?
Heh heh, I think it’s exactly the point. What happens when neophyte hits hurdle? It’s always been my assumption (and assertion) that we need to give newbies a fair go - give them a flute that lies naturally close to tune. Let them concentrate on all the other issues a newbie flute player faces - tone, breathing, phrasing, musicality, etc, etc. Others argue that what doesn’t kill us makes us stronger - struggling with an out-of-tune flute will improve our embouchure control.
Focusing on the plain cylinder, I suspect the deviations to be beyond the newbie’s ability to correct. I’m not even sure a good player could correct them, and I further suspect that, if anyone can, it will be at the expense of learning bad habits - specifically overblowing - that will have to be unlearned later. But these are suspicions, and you are in a position to illuminate them. Give it a go!
Actually I think we need to compare four things, namely playing without trying much to play in tune, and playing while doing your best to play in tune; both with and without the wedge. Don’t plead lack of time - a few minutes recording 4 mp3 files is all that’s needed. Just fire the mp3s off to Terry and we can all SEE what difference the wedge makes to your tuning.
Then what we need is some really good player doing the same thing…
I have three Tipple D flutes, of cylinder bore, each having the lip plate and the wedge, and I’ve discovered that these flutes simply don’t need the wedge.
Granted, a beginner could experience multitudinous troubles at getting the gamut of such flutes to play in tune, but playing in tune indeed can be done.
And, there’s no need to overblow them to do so, as it’s just a matter of correctly focusing the air stream, to get and to keep them in tune.
Let me add, however, that a better made flute simply doesn’t call for such embouchure gymnastics.
BTW, Terry, I’ve heard wonderful things about your flutes!
I agree with Terry that it is important to give newbies a flute that lies naturally close in tune. Even though I bow to Terry’s expertise and many years of flutemaking experience, I do take issue with his comment that the pitch deviations in cylindrical-bore flutes are beyond the newbie’s ability to correct. I have made hundreds of cylindrical flutes with a modified Fajardo wedge headjoint insert, and the feedback from both beginning and mature players indicate they are pleased with the tuning of the flute, at least for the commonly-used first two octaves.
Terry, I have a number of audio recordings of my cylindrical-bore flutes on the “audio files” page at my website. Jem Hammond has also recorded 7 videos of him playing my flutes, and these can by found at my YouTube channel listed below. You are free to sample any of these recordings with your pitch-recording software. I suspect that you will find pitch deviations, as I can easily hear similar pitch deviations when listening to professionally-recorded CDs of ITM tunes. Ultimately, as others have mentioned here on the forum, the responsibility for playing the flute in tune lies with the player. A good flute makes it easier for the player to accomplish that end, but it does not guarantee it.
FWIW, my intonation is by no means perfect, on the clips I did for Doug or anywhere else on any flute!!! All the clips I did for Doug were with the wedge in because without it I consider it virtually impossible to play acceptably consistently in tune. Yes, if you play one of Doug’s or even one of my own conduit-tube flutes I made years ago without the wedge, it is possible to do a fair amount to lip them into tune and with constant practice upon them I daresay one could become fairly consistent at it, but there are obvious reasons why that isn’t really a good idea. I disagree with Cork on this. I also disagree that the lip-plate makes a significant difference to intonation or ease of lipping it - I don’t think it does.
By way of I hope an illustrative story… back when I did my own experiments with PVC culinder flutes, I though I was doing really pretty well with tuning them for play through two octave. I then had an opportunity to show the better ones I’d made to Mike McGoldrick, who played them, said they made a very good sound, but were noticeably flat in the 2nd octave! I could hear it in his playing of them too, whereas in working on them and using a tuner in doing so, I thought I had gone a long way to curing the problem. Clearly I had become used to lipping them and was doing so unconsciously while trying to tune them - a perpetual bedevillment of the flute-maker, of course! I was also able to show them to Chris Wilkes with the same result…which effectively put the kybosh on them. At the time I’d never heard of the Fajardo Wedge and couldn’t think of an accessible/economical way to make either a Bohm head or a tapered body to effect the necessary tuning corrections (pace another recent thread!) - and I gave up trying to re-invent the wheel until more recently I came across Doug’s work.
Like my old experiments, I think Doug’s flutes without the wedge and probably Hammy Hamilton’s practice flutes (going on hearsay, here - I haven’t gotten to try one) have optimised the tuning within the limitations imposed by using commercially available tubing with little choice over the ID and therefore over the scale-length to bore ratio (which is one of the variables that can be manipulated to minimise the tuning issues - at the expense of compromises with tone quality and strength and response in different 8ves), but bottom line is that the 2nd 8ve goes significantly flat without a compensating mechanism. I’m with Terry in thinking it is futile to struggle with this fact as a palyer, especially as a beginner. Doug’s wedge is very effective and substantially provides a very tolerably satisfactory (though not perfect) compensation - and that is why I have previously advocated that he should make his flutes with a fixed-in wedge as his default product.
Re: RTTA tests, as Doug says, Terry is welcome to do them on the clips on Doug’s YouTube channel - and I will try to find time in the near future to do some comparative clips with and without wedge on one of my larger embouchure cut heads on a Tipple flute - I will do my best to keep a neutral/consistent embouchure for both options to try to provide as objective as possible a comparison.
No problem with the wedged cylindrical flutes (at least in theory, you’d need to check the tuning to ensure that the wedge was the optimum size). As you’ll see from my words above that I’m concerned about newbies buying plain cylinder flutes. Theoretically, these are going to run about 60 cents flat in the second octave, assuming the low octave is set in tune. In practical terms, I imagine they never run that flat as even a newbie will feel constrained to correct the flat upper octave. But 60 cents is too much to lip, so I imagine that the newbie will be forced to try to blast the 2nd octave up, by sheer jet speed. This seems to me to be a bad habit to ingrain in the early days, especially as a lot of conical flutes tend to be sharp in the same region, and require lipping down.
Now the word “imagine” appears there a few times, and the truth is I have never measured a plain cylinder flute to confirm or explode the theory. I don’t even have one, although I could obviously make one. Ideally though, it shouldn’t be me doing the blowing! This is why I’m encouraging someone (Dan, Jem, others?) to feed me some playing on plain and wedged cylinder flutes so we can really check it out.
Now, while I have you, Doug, have you (or anybody else?) ever tried to make a conically-wedged flute? I’m imagining a plain cylinder flute, with a long, slowly tapered wedge of the same material in the fingerholes region, to emulate the tapering bore of a conical flute.
One of the problems with the head wedge is that it is in a region of spiralling air column, and this can cause some aerodynamic loss. A wedge further down the flute would not suffer this (although the leading edge of the wedge would need to be smoothly chamfered to avoid it becoming an aerodynamic obstacle). Further a conically-wedged flute would exhibit the darker tonal characteristics and higher resistance of a conical flute. Variations in the shape of the wedge would enable the octaves to be tuned very well, and so the flute should have strong resonance all over the range.
Coming up with the dimensions of the wedge will require a bit of fiddling, but I’d be happy to collude on that. First thing to do is to make sure such a thing would be practical to make. Anyone up for it?
Most of the flutes that I have made play noticeably flat in the upper end of the second octave without the addition of the wedge in the headjoint against the tuning cork. However, I did notice that on at least one or two of the flutes that I sent to Cork (they were experimentally-cut embouchures with the small round shape and an aggressive cut to the front and sides of the embouchure hole), the intonation was pretty good throughout two octaves without the wedge, needing very little adjustment from the player. I should have been more scientific and recorded the measurements of the embouchure cut, but I didn’t. For reasons other than intonation I decided to back off somewhat on the aggressive embouchure cut for my following flutes. Like Jem mentioned, it is sometimes hard for me to access the potential of a flute after it is made and I am playing it for the first time. When I see that it plays well and in tune, my tendency is to get it in the box and off to the customer.
Terry, when you used the term “plain cylinder flute”, I thought that you were distinguishing a plain cylinder flute from a conical-bore flute. By this understanding, my flutes are indeed plain cylinder flutes with the addition of a wedge. However, as you have said, you were using the term “plain cylinder flutes” to mean cylindrical-bore flutes without a wedge or any other intonation adjusting device. It’s easy to misinterpret simple terms.
I do believe that the wedge in the headjoint of the flute does cause some aerodynamic loss. However, in the case of the cylindrical-bore flute, this may be a good thing. Cylindrical-bore flutes tend to have a pure tone, much like the tone of a concert flute, whereas conical-bore flutes have a darker tone that is seen as more desirable for ITM, for example. The wedge does interfere with the spiralling air column resulting in a more complex tone without causing a significant loss in the volume of the flute tone. Thus, the wedge in the headjoint accomplishes two desirable functions: 1) Like the parabolic taper in the Boehm headjoint of a concert flute, the Fajardo wedge similarly adjusts the second octave intonation to standard pitch. 2) The presence of the wedge adds complexity to the tone of the flute, making it sound more like a conical-bore Irish flute than a silver concert flute.
I ought to be able to give this a try using the middle-sized conduit tube inside the larger - it isn’t quite a snug fit and would require heat-molding out to fit the walls of the main tube snugly. I could probably reasonably easily make such a thing to fit inside one of my old body tubes or even one of Doug’s. The possibilities are severely limited, however, by the fixed dimensions of the pre-formed tubing, particularly the wall thickness. I suspect even a wedge expanding to a full tube section at the foot end might not supply sufficient bore compression/taper to be a complete tuning fix. Of course, simply sticking such a long wedge in a pre-made body tube might well not be an adequate experiment as it would have to work with the existing tone-hole sizes/placements, which might well no longer be appropriate. It might be necessary to make a new body and drill and tune the tone-holes to new specs.
Terry, if you want to work out a set of dimensions to work to, I’ll give it a whirl. The tube available to me has the following nominal dimensions (in fact the tubes are usuallly slightly undersize by between 0.1-0.2mm):-
Large: OD 25mm, wall thickness 2mm (actual ID usually c20.9mm)
Medium: OD 20mm, wall thickness 2mm (actual ID usually c 16.5mm)
Small: OD 16mm, wall thickness 1.5mm (actual ID usually c 12.4mm).
The body tubes for my already made D flutes (short foot) are c40cm.
If you need any other details, let me know.
Re: your comments on the disruption causedby a head wedge, I think you are right- I certainly notice some effect - but I have a plan I’m nearly ready to try which may substantially obviate that - which I’ve discussed with Doug: to whit, instead of a lip-plate to increase embouchure chimney depth, fixing the internal wedge before drilling the embouchure and then making the embouchure through the wedge - thus providing the extra chimney depth, obviating the need to fix an external lip-plate as well as a wedge (the OD of the tube is already quite fat enough and doesn’t need a lip-late for playing comfort) and, I suspect, significantly reducing the turbulence cause by the wedge. Gonna be interesting!
All the clips I did for Doug were with the wedge in because without it I consider it virtually impossible to play acceptably consistently in tune. Yes, if you play one of Doug’s or even one of my own conduit-tube flutes I made years ago without the wedge, it is possible to do a fair amount to lip them into tune and with constant practice upon them I daresay one could become fairly consistent at it, but there are obvious reasons why that isn’t really a good idea. I disagree with Cork on this. I also disagree that the lip-plate makes a significant difference to intonation or ease of lipping it - I don’t think it does.