A thread on harmonica playing got me thinking about this.Any one who plays mouth harp regularly will know that it has a limited life span due to out of tune-ness caused by metal fatigue of the brass reeds.Sometime ago I offered to retune a very old brass Gen D that had seen better days and found it extemely dificult to tune in comparison to a new unplayed Gen.Now a lot us feel that whistles do improve with age, but I also wonder if metal fatigue eventualy sets in making our prized whistles unplayable and if there are things we can do to offset this process. Mike
I’m going back a number of years here, but I seem to remember from a college Materials Science class that fatigue is caused by repeated movement of an object, such as through flexing or bending. So I could see where metal harmonica reeds would have this problem, but I don’t see a whistle having this problem, since there are no moving parts.
John Mac
If they cryogenically froze the harmonica before use, it would probably have lasted 3 times longer before going out of tune.
Not exactly right John:
Non-moving metal is subect to “work hardening” or “wear hardening” due to shock or vibration as well as metal that is “Flexed” - this is why (Safe) Mountaineers and Rock Climbers avoid banging their equipment around whenever possible, and this is also why they replace harnesses with critical metal buckles, as well as their aluminum carabiners, at regular intervals - one doesn’t want to trust one’s life to a piece of aluminum that may have become brittle due to the wear hardening caused by excessive shocks and vibrations over a long period of time.
So, bang your whistle on a table, or knock it against another whistle in your sock drawer, and even if it’s not enough to cause a dent, the impact will have a slight work hardening effect on that small area of metal.
Metal Fatigue/Work Hardening is mostly cumlitive and, in general, it takes many times more small shocks to achieve the same amount of hardening/fatigue as several large shocks. Flexing is generally more damaging than little shocks that aren’t enough to cause flexing.
Now, are the numerous little bumps and dings your whistles suffer over their life time enough to cause a difference in tone or playability? I have no idea. Most likely a whistle that’s banged around a lot during it’s lifetime, only ends it’s life more brittle than it started.
Now, whos in the mood for some annealing?
Loren
[ This Message was edited by: Loren on 2002-10-23 12:25 ]
Merty Millner wrote: If they cryogenically froze the harmonica before use, it would probably have lasted 3 times longer before going out of tune.
Man, I am cracking up on the floor over here. LOL LOL LOL Thanks so much for adding to the content of this website. Sorry I have to stop, my sides are hurting.
John Mac
I wonder if there is a difference in the way metals age and change over time for the different metals whistles and other instruments are made of?
Off the top of my head, that would include tin, brass, nickel, silver, and steel, as well as all the stuff I’m not remembering right now.
Fascinating subject.
–James
http://www.flutesite.com
Loren,
Thanks for the info. That’s why I went into software.
John Mac
On 2002-10-23 12:01, peeplj wrote:
I wonder if there is a difference in the way metals age and change over time for the different metals whistles and other instruments are made of?
Yes, there are differences, not just based on the metal type (compostion) alone, but also what state the metal was in at the time it was formed: How hard was the metal, had it been tempered/annealed etc. Heat treating metal can maker it stronger/harder or have the opposite effect, depending on a variety of factors:
A good forged/heat treated modern sport fencing blade is incredibly strong and flexable - it’ll bend (in an arc) nearly 180 degrees without breaking. And it can with withstand thousands of these extreme flexations, at very high speed (speed of flexing usually increases metal fatigue significantly), before it fails.
OTH an equally well made (but differently formed and heat treated) non-sport sword or Rapier blade will snap at somwhere less than 90 degrees - and perhaps even at 20-30 degrees if the flexing happens rapidly or often.
There are a lot of factors involved - it’s a pretty complicated subject, that I’ve somewhat oversimplified, to be sure.
Loren
[ This Message was edited by: Loren on 2002-10-23 12:44 ]
On 2002-10-23 11:46, Loren wrote:
Now, whos in the mood for some annealing?
My ankle still hasn’t recovered enough flexiblity to anneal for very long.
I understand the ‘breaking in’ of a wooden whistle, but in general a metal/plastic fipple sort of whistle. . .I can’t see what ‘breaks in’. Could the use of it do micro-wear on the blade? Imperfections on the fingerholes? Or (once again) is it the whistler being broken in on the nuances of this particular whistle?
Metal seems to be the subject here today so I add this twist:
Does anyone think that aluminum whistles change more than brass while they are being played from warmth or whatever?
The reason I ask is that as I was playing my Burke AlPro D this morning, it reached a point where the high A and B started getting weak and cottony sounding. This also happened the other night. I havent had this happen to the brass one so I am wondering if the softness of the metal means that the character changes substantially more will warm…
As the other night was during a band practice, where I was the newcomer, it was sort of embarassing to have the thing poop out.
I do remember a thread a while back in which Mary Bergin (or somebody famous) said that the whistles go out of tune, tho I doubt she plays aluminum whistles…
Thoughts?
Well, I’m no metallurgist, (and I don’t play one on TV), but here’s a bit on work-hardening of metals. Though it addresses heating as a cause, there are others, such as impact and vibration.
http://www.manufacturingcenter.com/tooling/archives/0799/799sht.asp
In silversmithing (and with most other metals), drawing material through a wire die will harden the material in just a few passes, to a point where you must anneal it to continue.
In some metals, crystallization takes place over time, witness old “classic” cars that have been stored without being driven. Oftentimes, parts will simply break the first time they are used. This usually applies to cast ferrous (iron and steel), but might also be applicable to brass, nickel, and other metals.
Any metallurgists out there have comments?
Cheers,
Bill Whedon
(speaking of answering some of one’s own questions) Excerpt from a Web article on Ottoman-period braziers:
“They were generally made of copper or brass, the latter being an alloy of copper and zinc, and yellow in tone in contrast to the red of copper. Since it is a work hardening metal, care must be taken when annealing not to overheat, as it then becomes brittle when hammered and can result in cracking and breaking.”
So, maybe the whistle brass was annealed at too high a temp? Lots of room here for speculation, huh?
Cheers,
Bill Whedon
Week, thermal expansion properties are differnt for brass and aluminum. I found a nifty little chart that shows the thermal expansion coefficient for various allows. It is intersting and pertains to several of the threads going on now about different metals. Check it out:
http://www.scinfitech.com/engineerresource/property/lineartherm.html
Well then I want an INVAR whistle that will stay the same when I play it (yuk-yuk). Wotinell is INVAR???
I never knew about more than one kind of brass tho… are ours whistles yellow or naval? Or somethin else…
Hm.
I never knew about more than one kind of brass tho… are ours whistles yellow or naval? Or somethin else…
Hm.
I think my Generation is naval lint
I know very little about metal, but as a classical flute player, I can say that some 100 year old flutes are highly prized because they were work-hardened (sheets of maillechort or silver were banged out into appropriate flatness and then formed into a tube and then banged into shape some more). These flutes definitely sound different from new flutes, although other factors are at play as well, for sure. (Older silver flutes in general have a different sound…I don’t know if it’s because the metal has been around for 50-plus years…)
However (and this seems to run contrary to what I just said), my teacher, among others, thinks that flutes eventually get “played out” and no longer play as well or sound as good. Her Powell flute is from the early seventies, and she thinks it is becoming “played out.” I have no explaination for this phenemenon.
Finally, cryogenic freezing is used by some flute companies on headjoints…it has something to do with hardening the metal or aligning the molecules, as far as I understand.
Micah
Okay, new place to store Burkes: IN THE FREEZER! HA! Burglars will never find em…
As if…
On 2002-10-23 11:42, Martin Milner wrote:
If they cryogenically froze the harmonica before use, it would probably have lasted 3 times longer before going out of tune.
Martin,would you or anyone else care to explain this further and what sort of things, if any, cyrogenics play a part in increased longevity of metals.I just got in so if its already been discussed further down,apoligies.
Mike
No need as I just saw the previous and cryo whistle thread. Crool stuff.
Mike
[ This Message was edited by: mike.r on 2002-10-23 17:18 ]
[ This Message was edited by: mike.r on 2002-10-23 17:24 ]
I remember in the 80,s that some guitar players stored guitar strings(brass/phosphor bronze) in the freezer,claiming long life as the benefit.I,m thinking now If I had taken there example I could afford some very nice high end whistles with the money saved all those years.From today my Gens are going in the fridge.
Mike
I’ve decided to keep all of my whistles outside all winter long. Maybe -60 is close to cryogenic temps?
Erik