Anyone have an easy solution for fixing a cracked mouthpiece?
What kind of whistle is it? And where is it cracked?
If it’s a plastic-headed whistle, and the mouthpiece is cracked on the part that slips over the metal tube, I’ve had luck with plain old superglue. Glue it together, let it dry, then go around it with twine and glue it again. That’s what I did (on a Gen).
If it’s a wooden whistle (for example) and/or cracked directly on the part you blow or the blade, then the solution will be different…
I cracked the mouthpieces on a walton and a feadog. The Walton has 3 cracks and the feadog is cracked right down the middle. Thanks for the help, Cranberry. By the way, nice avatar. 
On the Feadog, I have had the same problem. I used super glue and tape to pull it together. It plays beautifully. I have repaired this one several times because it is so good. I bought a Feadog Pro and another brass to supplement my Feadog sound. The Waltons you can try the same thing. If it doesn’t work get another one.
Ron
Well, I’m not really concerned about the Walton. The cracking is probably my own fault. I think I applied to much pressure when turning them straight. 
Thanks for the tips Mr. Kiley.
The good news is that Waltons are pretty consistent from whistle to whistle and from type to type, so if you break one you can get another quite easily, whereas if you destroyed a “good” Gen, it would be another story.
On the Feadog it is a common issue. The MkIII head has a faint line running longways down the head on the window side. Occasionally this does develop into a crack. This line is a weak point left from the production process.
On Feadogs I have bought recently the line seems less visible, and I haven’t had one crack for some time.
To be honest I just discard the heads if they do crack.
Alright, thanks for all the help. I guess you’re right about the Walton Cranberry.