Steve Bliven wrote:
And I, unfortunately, got a black top and that sucker won't move. Tried just twisting, tried hot water, tried several incantations, tried several explicatives, and it still won't move.
Hmm... you could take the temperature-difference thing further. Put the whistle in the freezer for 5-10 minutes (assembled so that you've got more cold mass), *then* put the head in really hot (but still not boiling) water. (Of course you'll want to use a towel around the cold metal of the tube, and if the water is too hot or you keep the head dunked too long, you can warp the head enough to damage its ability to make sound, so be careful!) I *think* this method has helped me with tight heads, although it's also possible that I'd just been yanking and twisting at them long enough.
Another approach, which I believe is Jerry Freeman's preferred method, is to slide just a bit of the top joint of the whistle into a larger tube (conveniently, a C whistle is ideally sized for this), hold the larger tube by the end with the whistle in it, and then "throw" the larger tube with a quick snap of the wrist, like you're shaking down a mercury thermometer. The D whistle will slide into the larger tube and the head will hit the end of the tube with enough force that, in theory, you should be able to dislodge it.
That said, you're at a massive disadvantage with the Clare -- literally, in that there's less mass to the top joint, and it's the force (and therefore the mass) of the movement of the D whistle's brass tube that determines the force that'll pop the head off. And I never got this method to work with my (new) Gen D, which has a full-length tube (and therefore over twice as much mass). Still, there might be some way to rig this sort of thing up, to get a greater velocity for the top joint. That wouldn't be hard if you have access to a big enough centrifuge... not that you heard such an idea from me, of course....