Re: [Harp-L] Carbon Fiber Reeds, 3D printing, plastic metal adhesion technology...?

[David Payne <dave@xxxxxxxxxxxxxxxxxxxxxx>]

Carbon fiber reeds keep coming up in mention. I've never quite understood the alure of it, because, to an archer like me - surprise, I prefer wood arrows (I'm a longbow man) - having used carbon-fiber arrows, seen them break and the long, sharp shards created when they do, it seems about the most dangerous thing you could make a reed out of. I would literally rather have a reed made out of 100 % pure Columbian lead.
 
But even ignoring safety issues, even if I were wrong about that, I don't think carbon fiber has the right properties.
 
I shoot wood arrows, not just because I'm a woodophile, it's because of the properties of the two materials. Let's say you shoot a carbon fiber arrow into a wall dead on. It will probably be fine. Wood arrow will crush at the tip. I can still be an arrow, only an inch shorter arrower perhaps. 
Now shoot the wood arrow to strike a glancing blow against the wall. It will skip off and go about it's merry way downrange, it will even recover and fly straight. Shoot the carbon fiber arrow that way and it will shatter into two large shard-ridden pieces, plus a nice dusting of smaller shards. 
 
How do I know this? From shooting wood arrows at cinderblock walls. I went to this cool indoor archery range when I was in college. It was a hangout for traditional (recurve and longbow, no training wheels) archers and they us do some neat stuff, like dangle snuff cans from the ceiling with a long cord, swing them like a pendulum and shoot at them with arrows. When you do stuff like that at an indoor range, you wind up with a LOT of arrows bouncing off walls.
 
I would surmise that the stresses upon a carbon reed would be similar to that carbon fiber arrow glancing off a wall, only repeated a few hundred times each minute. That's a major reason I've never considered carbon fiber a realistic reed material.  

David Payne
www.elkriverharmonicas.com
www.hetrickharmonica.com
 

________________________________
 From: Joseph Leone <3n037@xxxxxxxxxxx>
To: Mike Wilbur <mike@xxxxxxxxxxxxxxxxx> 
Cc: Harp L Harp L <harp-l@xxxxxxxxxx> 
Sent: Thursday, February 21, 2013 12:09 AM
Subject: Re: [Harp-L] Carbon Fiber Reeds, 3D printing, plastic metal adhesion technology...?
  

On Feb 20, 2013, at 11:57 PM, Mike Wilbur wrote:

> Believe me Carbon Fiber Fishing Rods, fly fishing and spinning and trolling and plug casting are alive and well and the "state of the art" ..... one uses fiberglass fishing rods anymore.
> Well Nimrods do !

I agree, carbon rods are great...UNTIL they break. And yes Mike, I AM living in 1913...an old nimrod.... lolol (Btw, I use glass rods because they're free...ha ha ha). Ole cheapie me. 
> 
> Having said that a hole in Carbon Fiber is the beginning of the end....they / it will shatter.

Kinda what I was sayne. :)
> 
> Also the breathing of Carbon Fiber Dust would be equal to many years of smoking cigarettes.
> Or Coal Miners Black Lung !

Uh-huh, I used carbon fibre on my recurve and long bows. For some things it's great stuff. But not everything.  :)
smo-joe
> 
> 
> 
> Mike Wilbur
> 
> 
> On Feb 20, 2013, at 11:40 PM, Joseph Leone <3n037@xxxxxxxxxxx> wrote:
> 
>> 
>> On Feb 20, 2013, at 3:43 PM, Vern wrote:
>> 
>>> 
>>> On Feb 20, 2013, at 12:06 PM, John Ingham wrote:
>>> 
>>>> What can you tell me about the possibility of carbon fiber reeds,
>>>> products, experimentation. Is that just a crazy notion?
>>>> 
>>> 
>>> Carbon fiber has a very high strength-to-weight ratio making it ideal for many vehicle applications, particularly aircraft.  It has another desirable property in that the epoxy matrix absorbs vibrational energy.  However, these properties may make it less desirable for reeds which act as springs.  To my knowledge, carbon-fiber composite is not used for springs.
>>> 
>>> In reeds, you want a material that stores, not absorbs vibrational energy.  The pitch of a reed is determined by the square root of (k/m) where k is the "springiness" of the reed near the rivet where it bends and m is the weight near the tip that deflects.  You would probably have to attach a weight near the tip of a carbon reed to achieve the customary pitch-length relationship.
>>> 
>>> IF it were not for rust, spring steel would be the ideal material.  If you want to experiment, maybe a thin, protective coating could be developed.  Manufacturing spring steel and tuning would be problems to be solved.  The material that makes the best spring makes the best reed!
>>> 
>>> Vern  
>> 
>> 
>> Three things I can think of.
>> 1...There WERE springs made of carbon fibre. They were on the Chevy II from the early 60s. They didn't work too well. Apparently when you put a hole in it (somewhere?), spider fractures start. I see a carbon fibre reed needing to be GLUED. Screws or rivets would qualify as holes..and that would be NON good. :(
>> 
>> 2...In several America's cup yacht races, carbon fibre parts failed (masts, booms, spinnaker poles, block cheeks), causing the LEAD boats to loose their heats, and ultimately the cup. A sad state of  affairs for millions and millions invested...for naught. :(
>> 
>> 3...Steel CAN be used for reeds. I have done it. First used a Gillette super blue blade, then a Schick copper clad. Finally a Wilkinson sword stainless. The steel reeds were ok as long as you
>> opened the harp from time to time and rubbed candle wax on the edges. (The flat surfaces were already coated). And I like the idea of a protective coating. :)
>> 
>> 4...Ooooh, I just thought of another. Carbon fishing poles ARE springs. They also suck. Real good if you want a light rod and a sporting good time. BUT when they fracture, they virtually BLOW apart.
>> I have at least 16 rods in my bedroom closet which I have found in the marina dumpsters and re-built, They are ALL fiberglass. ALL the discarded carbon rods were junk. Un salvageable. :(
>> 
>> I agree with Vern that carbon fibre presents many challenges. Me? I would give it a shot. Sort of a Mt. Kilimanjaro to conquer. :)
>> 
>> smo-joe  
>> 
>>