I have made several whistles out of cpvc, using the info for the Low Tech Whistle and the Twcalc program to figure out where to put the tone holes. I made a Low F whistle out of 3/4 cpvc, it was pretty well in tune and a more breathy than I would like. I have since made 2 more of the Low F’s. I tried a High D and it was very quiet and sounded nice on the bottom end but when I played into the second octave it got very scratchy. I reworked the labium ramp and the fipple plug and refigured the tone holes and now it is a very quiet whistle and very sweet sounding.
I am a machinist and the manufacturing part is not a problem (so far 
) I have found a lot of information on the web about whistle making, and a lot of it seems to disagree. One site says the knife edge should be just slightly above the windway floor, and the next says it should be half way between the top and and bottom of the windway. Which side of the ramp to sharpened top or bottom. The size of the window relating to volume. Etc.
I realize that the apparent dissagreements may be what works for that particular design.
There are a multitude of variables that all impact the design and sound and how it plays.
Where can I find information to help me sort this out, and point me in a more focused direction. At this point I don’t know enough to know what to change and what not to.
My goal is to eventually be able to make myself some nice looking and sounding whistles.
Any informtion/help/pointers would be greatly appreciated.
Thanks!
FWIW-- the bottom of my blades are exactly in line with the top of the fipple. This is inherent in the design.
There’s no “right” place for the edge to be, or shape to the edge even, without all the other parameters being known. The whole sound-making business is due to the interraction of lots of things going on in the head of the whistle.
That said, most ramps I have seen are positioned at the bottom of the windway. This might be due to the fact that the easier methods of making the windway and fipple tend to result in a design that works well with it there.
If you are generally following Guido’s instructions, then also follow his advice about the labium ramp. He know of what he speaks!
What are you using for a plug? If it is wood did you make it glass smooth for the windway? If 220 grit sandpaper is used to size the plug than go to 400 and make it smooth. Then wet it and let the wood grain raise. To speed things up use a hair dryer to dry the plug. Then sand it smooth with 600. You can get 1000 and 2000 at a auto parts store in the paint and body dept. Wet the plug, dry and sand at least three times to get it very smooth. If you are using wood dowels from the hardware store and there is no clue to what kind of wood they are. Make some plugs from cedar. The moisture will not affect them as much as cheap dowel wood.
gregdidge,
It sounds like you have gotten to the place where whistle making becomes a lot of fun. Really!
I made a Low F whistle out of 3/4 cpvc, it was pretty well in tune and a more breathy than I would like.
Are using the ivory colored 3/4" cpvc? The bore diameter is well suited for making good low G and low F whistles. Did you follow Guido’s design for the mouthpiece? The wall thickness of the tube determines the windway height in the Low Tech whistle. I would suggest that the breathiness may come from the height of the windway. Guido uses tubing with a comparatively thin wall. And that works well.
There are a multitude of variables that all impact the design and sound and how it plays.
Yep, you are correct! Start making whistles varying some of those parameters. Take notes on what characteristics change as you vary the parameters. Think about why that happens. When you get to a combination that produces the sound you like, there is nothing left to do but make more whistles. It’s great fun. It might take some time but you can discover a lot.
My goal is to eventually be able to make myself some nice looking and sounding whistles.
This is very doable. Good luck.
Feadoggie
Here is my $0.002 worth:
It seems to me that the cause of breathyness is turbulence in the airstream. The airway needs to be really smooth inside and the entry and exit points of the airway need close attention. I tend to round the plug a little where the air exits and that seems to cure some breathyness. Also, if the blade is very sharp, that seems to cause it in the high octave.
Thanks for all the feedback!
Start off rounding the plug just a tiny bit. If the low notes are weak and tend to break into the second octave too easily, round the plug a tiny bit more. If you go too far, you’ll get really solid low notes, but will have to blow very hard to get the second octave. Somewhere in between is that perfect spot.