What would be the average wall thickness of wooden whistles, and how does thickness affect it?
Also what would be the normal wall thickness of metal tuning slides, and what would be the preferred metal?
And last question, does the wall thickness of the body affect the responsiveness of the whistle?
talking about high D’s here
thanks in advance 
chrisp, wall thickness varies from maker to maker according to their design. It’s just one of many variables that each maker determines during their design process. I am reluctant to quote an average thickness. Wall thickness itself does not determine responsiveness, IMHO. Hole size and efficiency is a big factor, again, IMHO.
These can vary too. Some makers draw their own tubes, some order custom drawn tubes but a number use stock sizes of K&S brass tubing. It is available from here.
http://www.specialshapes.com/brasstubing.asp?product=014
There are other online sources as well. It is also widely available here in the US through many hobby and craft shops. The wall thickness I use is the .014" tubing for the high D’s. The diameter you use depends on the bore size of your design. You want the inside diameter of the smaller tube to match your bore diameter ideally. K&S is telescoping tubing, meaning that each successive size fits neatly inside the next larger size. Even with that, the two tubes slide too easily to hold the tuning position in place. Most makers persuade the inner tube to be a tighter fit. “Persuade” in this case means you expand the diameter of the inner tube a little bit for a firmer fit by whatever means works for you. You could also use a wax, like beeswax, to make the fit a little more firm.
Hope that helps.
Feadoggie
Thanks for the information 
surely the body’s wall thickness affects something? I haven’t seen any whistles as fat as me yet 
Excuse my ignorance but what is IMHO?
IMHO =“In my humble opinion”
The wall thickness of my wooden whistles is around 2.4 mm.
WOW… lovely whistles O’Brian
how long have you been making?
My whistles have an ID of .500",OD of .656"
The tuning slides are thin walled telescoping brass tubing, 9/16", and 17/32"
Note that these sit in bored recesses in the wooden wall of the whistle.
My slides are the same dims as Paul’s. The ID of the 17/32 is 0.5 in., the same as my whistles.
I’ve been making whistles since the 80’s, but wooden ones for the last 4 or 5 years.
There is something about these beautiful wooden whistles.
They are both tactile and a piece of art.
got to have a go myself, and it’s fantastic to get this feedback from people that put the heart into their work.
there’s nothing like making something beautiful with your hands and to then hopefully hear how beautiful it sounds.
Thanks to you all
I’ve got my hans on some 10 year old laburnum.
Does anyone know if it is still poisonous after ten years?
It’s a beautifully grained wood and heavy
A thicker wall means the hole is deeper which reduces its effective size (unless undercut) and so a whistle with thicker walls will have larger holes all other things being equal. This is something to watch out for even when using plastic plumbing tubing as though the OD is accurate (it has to be to macth the fittings) the ID varies.
Bill
Would it be this Laburnum?
From
http://www.ces.ncsu.edu/depts/hort/consumer/poison/Laburan.htm
Scientific Name
Laburnum anagyroides
Common Name
Golden chain tree
HIGHLY TOXIC, MAY BE FATAL IF EATEN!
Characteristics
Family
Fabaceae
Plant Description
Small, deciduous tree; leaves alternate, long-stalked with 3 leaflets; flowers pea-like, golden, in long drooping clusters; fruit a long, flattened pod.
Origin
Europe.
Where Found
Landscape as cultivated, woody flowering vine or small tree.
Mode
Ingestion.
Poisonous Part
All parts.
Symptoms
Nervousness, stomach and intestinal irritation with nausea, vomiting, and diarrhea; irregular pulse, convulsions, coma; may be fatal.
Toxic Principle
Cytisine, an alkaloid.
Severity
HIGHLY TOXIC, MAY BE FATAL IF EATEN!
Does not look like something I would want to turn or put in my mouth!
I knew it was poisonous, and certainly wouldn’t want to eat it whilst it were living. I wondered if it were still poisonous being dead(seasoned) for ten years?
I guess it wouldn’t be a wise thing though.
Just out of interest, are all woods that are used for whistle/flute safe to consume whilst living?
I don’t know the answer to that.
Edible and contact safe are different things, and just to throw something else in the mix walnut sawdust can make some people sick but it is commonly used for salad bowls as is the oil for oiling wooden bowls and utensils.
Best to stay away from Very toxic things and try to minimize your intake of any sawdust (or other fine dust - flour is not good for lungs either)
Bill
That’s a good point Highwood,
I bet the sap of a lot of woods are not nice to consume, including well known woods for whistles. PVC and some plastics are not good to breath in.
What about birch? Birch in this region of Norway grows very slowly due to the climate and creates a tight grain.
Rowan (mountain ash) grows slowly here too. It would be nice to try a native wood. Any thoughts on these two?
A.H.Benade and Lew Paxton Price recommend a wall thickness of at least 1/8th inch at the voicing or it will be very difficult to generate oscillations. I find this true in my experience.
The thickness of the Tube Material at the voicing (ID to OD) can average between 1/16th and 5/8ths inches, but this is not a set “rule”. Sound waves travel through solid materials faster than air (Young’s Modulus). This means that the more mass/atoms a material has, the faster sound will travel in it. Hardness is also a factor (harder/faster).
Example: A concert german silver flute is more dense than a wooden flute and will favor high frequency harmonics. The wooden flute will attenuate more of these frequencies in it’s softer mass and favor low frequency harmonics.
I find it best to keep the thickness at the toneholes to a minimum to reduce any flat tone at higher registers with more internal pressure. Higher aircolumn pressure pushes up into deep toneholes and increases internal cubic volume leading to flat tones. I try to stay at least a 16th though, or the finger pads intrude into the bore.
Tuning Slides: The prefered metal is German Silver (60/40-copper/sterling silver). This metal is cheap and once oxidized (reticulation) and polished, it resists corrosion. Bronze and Brass are used, but these copper alloy metals produce toxic verdigris (green copper oxide) when corroded.
You didn’t mention “Bore Perturbation” but… Restricting the bore just above a tonehole will increase aircolumn velocity and raise pitch. Conversely, increaseing the ID will do the opposite (E = 0.5mv2).
The combinations are Legion here, so I have generalized. questions? vengeful retortes? 
Mr T-H, I’m confused by
“The thickness of the bore (ID to OD) can average between 1/16th and 5/8ths inches”
The thickness of the bore is the ID and 1/16 is too small for a bore.
5/8 is too thick for a wall thickness.
I made an edit to clarify my last post. I was refering to the distance between the Inside Diameter(ID) and the Outside Diameter(OD). Example: ID = 0.5 and OD = 0.625 would leave a thickness of 0.125
This thickness is at the “Voicing Window” location. A Few rare historic Recorders have Labium ramps this deep. Deep voicings maintain pitch with changes in breath pressure, while shallow ramps (Tabor Pipe) allow greater pitch bending with changes in breath pressure.
Wouldn’t an OD of 0.625 inch and an ID of 0.500 inch give a wall thickness of 0.0625 inch? Sorry to be picky.
I’d love to get some German silver tubing: any idea where I can get it in the sizes I mentioned earlier?
With only a bit of effort, toxic green verdigris is not likely to be a problem.
I recommend disassembling a whistle when you’re done playing it and dry the bore and slide. The brass will develop a patina, but I’ve never seen any green meanies.
When I was working on my masters thesis, I came across a lot of information on the toxic effects of wood and wood dust. One interesting point was that not only does the composition of wood vary from species to species, but also from tree to tree in the same species. It also varies depending on what part of the tree the wood was from. The roots, trunk and branches can each have a different composition.
Exposure to the dust will produce the highest concentration of the toxic chemicals. Allergic reactions are the most common problem. Western red cedar has a chemical (plicatic acid) that is responsible for allergic reactions up to anaphalactic shock. On the other hand, cedar of lebanon and eastern red cedar don’t have it.
Oak dust has been linked to nasal cancer. The problems would be more of an issue to the woodworker since the dose level for anyone else would be so small as to approach zero.
There are so many woods that have centuries of use that I wouldn’t use other varieties without a lot of caution.
Angelo