WTT #4 - De Blade, Boss, De Blade!!

serpent · Post by **serpent** » Fri Oct 25, 2002 9:20 pm

I've seen blade sharpness all over the map. Sharp, rounded, square-edged - pretty much the gamut. Various thicknesses, too. Can we hear from someone on advantages/disadvantages of the different profiles?
Thanks,
Bill Whedon
(edit 1 to change subject)

[ This Message was edited by: serpent on 2002-10-29 19:53 ]

Ridseard · Post by **Ridseard** » Fri Oct 25, 2002 11:08 pm

I dunno nothin' about whistle construction, but from info about tweaks (on Gen type whistles), I've read that if it slips into the second octave too easily, then dulling the blade may help. However, if you dull it too much, then the second octave gets breathy-sounding. My tweaking experiments (and disasters) have verified this.

Another observation... Someone mentioned in one of the threads that the regular Susato SB has a dull blade and that the VSB has a sharp blade. Maybe this accounts for the fact that first to second octave transitions are much cleaner with the VSB than with the SB.

Zubivka · Post by **Zubivka** » Sat Oct 26, 2002 2:38 am

Tried yesterday to play a big laughing whistle, made in England under

Acme

brand. Nice low whistle sound with half the length, pretty pure.
The funny thing about it is the blade : more than dull, it looks like there's no blade. Just the tube, rather thick-walled, cut (rather, molded) straight in front of the windway.
However, I purchased another laughing whistle (Alto Ab...), clear+yellow+purple plastic for my 6-year old Sacha, he's having fun. The translucent tube makes the whistle look strangely like a veterinarian's syringe. The fipple is like a Generation, with a sharp blade, except it's made of a supple plastic. Sound is nice, a bit more chiffy.

Note both whistles are in tune

Is this the start of LafWhOA ?

--BbZH

mike.r · Post by **mike.r** » Sat Oct 26, 2002 4:41 am

On 2002-10-25 23:20, serpent wrote:
I've seen blade sharpness all over the map. Sharp, rounded, square-edged - pretty much the gamut. Various thicknesses, too. Can we hear from someone on advantages/disadvantages of the different profiles?
Thanks,
Bill Whedon

Saw tooth profile would be interesting..as a disadvantage example.

Seriously though Bill, I think a slight dulling of the blade offers tonal advantages.Somone once pointed out the tip of the nose of the Concord is actualy rounded and not pointed for better aerodynamics.Flute and fifes also benefit from a slightly radiused embouchure I,ve been told. Mike

[ This Message was edited by: mike.r on 2002-10-26 06:46 ]

brewerpaul · Post by **brewerpaul** » Sat Oct 26, 2002 5:45 am

My blades are a bit shy of razor sharp. On a wooden whistle this has the major advantage of keeping the blade stronger. If you thin it down to only a coupla wood fibres thick, the edge of the blade can warp and/or split as it resides in the high velocity , high moisture airstream. On some grainier woods, I coat the finished blade with a wood stabilizer, or even water thin cyanoacrylate glue to strengthen it. So far, none have come back for repairs.

brewerpaul · Post by **brewerpaul** » Sat Oct 26, 2002 5:46 am

Just had a thought-- I have 2 whistles which I will be voicing pretty soon ( purpleheart and pau rosa). As I do this ( files, diamond files, 400 grit sandpaper) I will test play them at various stages of blade sharpness, and make notes to share here.

serpent · Post by **serpent** » Sat Oct 26, 2002 8:17 am

On 2002-10-26 07:46, brewerpaul wrote:
Just had a thought-- I have 2 whistles which I will be voicing pretty soon ( purpleheart and pau rosa). As I do this ( files, diamond files, 400 grit sandpaper) I will test play them at various stages of blade sharpness, and make notes to share here.

WoooHooo! Thanks, Paul! I'll look forward to those notes!

As an aside - I've been keeping my blades less than razor-sharp, even tho using steel and copper (now brass, too), which are pretty much unaffected by the in-play moisture effects. Tried razor-sharp blades and they seem subtly less-easy to voice properly. Mike's observation about the Concorde is a good one. Same deal with bullets, most of which (hunting rounds) use a secant ogive as a nose shape for maximum velocity and stability in flight.

There, also, is a place we can pick up some ideas for the discussion on windways and turbulence!
Cheers,
Bill Whedon

Loren · Post by **Loren** » Sat Oct 26, 2002 9:27 am

On 2002-10-26 06:41, mike.r wrote:

Flute and fifes also benefit from a slightly radiused embouchure I,ve been told. Mike

Well Mike, I suppose it depends what you mean by "Slightly Radiused", I mean you're not going to cut yourself on a good flute or fife embouchure edge, but the fact is, the edge you blow on does need to be fairly sharp to give the best sound and response - only the back and (sometimes) the sides of the embouchure hole will get (noticabley) radiused, depending on the shape of the hole and the maker:

The blowing edge of the oval shaped embouchure hole on my Olwell is VERY sligtly Radiused, however most would call it sharp, I think. The Healy Flute I owned, which had a somewhat rectangular embouchure hole, had a blowing edge that you could almost cut yourself on, as does the Seery Polymer Flute I'm borrowing at the moment, which has a more Oval shape.

Loren

Loren · Post by **Loren** » Sat Oct 26, 2002 9:31 am

P.S. I suppose there will be a number of people who say: "Yeah but, I filed down the sharp edge of my (fill in the blank with cheap whistle name of your choice) and it sounded much better"

I'd suggest that the reason for this is that you actually smoothed out (as well as dulled) a ragged edge blade, which may or may not have actually been sharp to begin with. A ragged edge (sharp or dull) I should think is going to have a negative impact in the efforts to produce an instrument with good tone.

Loren

Brian Lee · Post by **Brian Lee** » Sat Oct 26, 2002 9:41 am

As a curious note to not only the sharpness, but the leading edge of the blade itself.

Aircraft manufacturers slant the wings of fast flying aircraft to improve stabitily at high speeds. Would it stand to reason then, that an angled blade might somehow improve the tone/overtone/playability of a whistle? I'm talking about the whole leading edge, not the sharpness, but the overall shape.

So if you look from the top down, onto a regular windo and blade, youi see a rectangular opening. I'm suggesting a blade shaped like a triangle, or wedge (possibly reversed too??) instead of the flat edge...

Thoughts????

Bri~

dkehoe · Post by **dkehoe** » Sat Oct 26, 2002 10:00 am

Are we forgetting that speeding bullets, Concordes and jet fighter wings travel at way higher Mach numbers than the relative movement of air and blade in a fipple? Nice ideas, but I just don't think they apply here.

Loren · Post by **Loren** » Sat Oct 26, 2002 11:10 am

I was thinking the same thing: Airflow reacts very differently at supersonic speeds when compared with the speeds we're talking about.

Once again we need a PhD., this time in aerodynamics, or.....a highly experienced maker of fine bladed woodwinds to accurately answer our questions.

But then those folks don't seem to be hanging around and contributing to these threads, do they? Okay maybe some are hanging around, so in the meantime, Paul's pending experiment not withstanding, we're back to the blind leading the blind via speculation. Not very scientific, or particularly enlightening........

Loren

dkehoe · Post by **dkehoe** » Sat Oct 26, 2002 12:01 pm

Loren, it could also be the the highly experienced makers of fine bladed instruments are just that - experienced. Now this is a good thing, except my guess is that most of them build their whistles based on what has worked before, not based on any fancy-schmancy scientific theory.

Fact is that the American Acoustical Society (of which I am not a member) still accepts papers on edgetone theory. The scientific details here are still being worked out.
In the end, these H.E.M.O.F.B.M.I.s probably are only passingly interested in discussions like this, because it probably doesn't result in them selling any more whistles. Or maybe I'm just being cynical.

jtbishop · Post by **jtbishop** » Sat Oct 26, 2002 12:22 pm

makers of fine bladed instruments are just that - experienced....most of them build their whistles based on what has worked before, not based on any fancy-schmancy scientific theory.

I would completly agree with this as many of the makers seem to have experimented and built up a knowledge of what works. (Didn't Fred Rose spend a decade doing this?)

I was lucky to see Jim Copeland tweak my whistle with a file utilising a rudimentary jig. I asked how he knew when to stop - no specific answer, he just knew when it felt right!

I think that the old adage, "practice makes perfect", applies here.

BTW what is/are H.E.M.O.F.B.M.I.s ?

dkehoe · Post by **dkehoe** » Sat Oct 26, 2002 12:57 pm

Highly experienced makers of fine bladed musical instruments.

(a reference to Loren's post)

Dave

[ This Message was edited by: dkehoe on 2002-10-26 14:59 ]