There is a long thread on the whistle forum discussing the possibility that whistles with Delrin plugs might go bad over time. It’s my guess that the Delrin plug is not the cause of the problem with the whistle in question. However, as I have been seriously considering the purchase of a Delrin
flute, I would like to know if anyone has had a problem with one losing it’s voice after years of playing?
The material would probably have a life of about 10,000 years, so it might last your lifetime. 
I think it’s a good question. I got to wondering the same thing after someone brought up the hydrophilic property of Delrin and its implications for fipple plugs, something I never knew of and wouldn’t have guessed.
Anyone know more about this and the implications for the flute side of things?
I have one… but its pretty new. A baby in fact. 
Will it last?
I’d say sure… yes.
Knowing the material properties of Derlin I would have to say you’d have to go quite out of your way to destroy it. Bury it and 400 years, dig it up, wash it off, replaces the tenon corks it and fire it up.
It doesn’t warp, crack, deform, swell, its hard to wear down and it laughs at most solvents.
I think high heat is probably its biggest foe… don’t go playing it if its over 200 degrees F. out.
As long as you don’t take knifes to it, throw it into the fire place or place it in low orbit it will most likely out last humanity.
So far, after some Googling, the best I can tell is that the hydrophilic nature of Delrin more implies simply that water is attracted to it, but water doesn’t necessarily dissolve or otherwise structurally compromise Delrin in any way we could consider significant. Would this be about right?
with all the dribble coming off the end of the Seery, i’da never thunk to hear the word “hydrophilic” associated with it 
seriously though, it would seem that a windway on a whistle would be a different story than the bore on a concert flute in terms of tolerance for moisture collection or surface degradation.
I’m particularly thinking in terms of the embouchure edge in this matter.
ah so.
even so, i’d think it no more hydrophilic than wood (likely considerably less), and we have examples of intact wood embouchures older than any natural human lifespan.
disclaimer: not a science guy (can you tell?)
I was thinking that, too, but for the possibility that the structure of wood might be the difference: Delrin having no fibrous bonded grain as we think of it, I had a vision of the stuff’s surface going sort of all gwooshy instead of smooth after years of water contact. Maybe it’s a non-issue, but whistlemakers caution against soaking Delrin heads in water. Questions, questions.
Birds of a feather. I am indulging in wildly idle speculations, what with no authoritative guidance on the issue so far.
I can’t imagine the pressures involved and the amount of liquid involved on a flute emouchure to ever cause a problem for it. Like wooden flutes, I’ve experienced gunk build up on the embouchure walls, but it’s easily cleaned with a q-tip and some warm water.
Granted, delrin really hasn’t been around long enough for us to know if it’ll degrade any 100 years from now, but there are ebonite flutes that are 100 years old out there still being played and not having problems. Granted, it’s another polymer, but it gives one hope…
I can’t recall where I read it, but I do recall reading that delrin doesn’t like chlorine or chlorinated water (an issue PVC does not have)…but the testing involved soaking it under water (or in pure chlorine) for 100 days. I can’t imagine rinsing it out, despite the noted whistle maker’s comments, with tap water would cause any problems. Even leaving it overnight in a glass of water shouldn’t cause a problem with the delrin (it is used in products where it’s wet 100% of the time in plumbing fixtures and fountains) - especially since the chlorine will air out overnight (old aquarium technique…which shows how old I am).
I think the whistle problem with delrin is related to cleaning. With a wooden whistle or flute, people really clean them - using a rag/cloth with oil on it is very good at removing gunk. With delrin things, people just tend to rinse them out…which doesn’t always remove deposits AND they can build up. On a flute, it would be less noticeable (except at the embouchure), but on a whistle windway, especially a tight one, it could cause problems.
Eric
Okay, this from the Whistle Forum where a clogging discussion led to Delrin questions parallel to those in this thread:
Thanks, Mitch!
I was sweating that alcohol thing.
(whew!)
