Re: [Harp-L] How the Turboslide actually works

[David Payne <dave@xxxxxxxxxxxxxxxxxxxxxx>]

That was a great post, Vern. I didn't mean to imply that the magnetic force affects density at all - what I meant was that the application of a strong magnetic field has the same effect as adding density, but instead of density, it's an application of force. It all makes sense in my head, but I know I can't communicate it clearly. Hopefully, there is an electrical engineer who also flyfishes.
I did a little flyfishing this morning and it all came to me.  
When you cast a flyrod, you are throwing the weight of the line only and it takes a very precise application of force with very precise timing to do this. Like a harmonica reed, the flyrod itself is a spring and it is, in the most basic sense, shaped like a harmonica reed - it is very thin at the top and thicker as you get closer to the reel (where the casting force is applied). 
If you just move a flyrod back and forth at a constant speed, you'll have a clump of coiled line at your feet. The force must be varied during the cast to make this happen. 
To get sharper, the reed has to go faster. The following scenario I believe represents what happens when magnetic force is applied to the base of the reed, making the reed go sharper.
Imagine you're looking at somebody casting a flyrod from the side and imagine there is a huge clock behind the angler. The flyrod go back and forth from  2 o'clock to 10 o'clock. OK, so the flyrod is behind the angler at 10 o'clock.  As he brings the rod forward, he will start very slowly, but he will be constantly increasing this force with his arm. By the time he reaches 1 o'clock, his arm will be moving very quickly and will continue  to increase the speed until he reaches the end of the cast. At that point, two O'clock, he stops and the tip of the flyrod surges forward very quickly. 
And that's how you throw 60 feet of flyline.
So what about when it goes back? It's the same thing in reverse. The anglers arm starts slowly then builds up speed. The speed climaxes at the very end of the backcast. 

Cracking a whip might be another analogy, but I cast flyrods a lot more than I crack whips, so I don't know much about that. But I do know, from flyfishing, that when you have a spring swinging back and forth applying force at the very end of its travel will make the tip go faster. When the tip goes faster, that's an increase in frequency, which, when you can hear it, means an increase in pitch. 

For the record, I'm not a 10 o'clock and 2 o'clock caster. I'm more 9:30 and 2:30.
(ducking)

David Payne
www.elkriverharmonicas.com


Elk River Harmonicas Forum now available via Iphone app, www.elkriverharmonicas.com/forum


________________________________
 From: Vern <jevern@xxxxxxx>
To: Joseph Leone <3n037@xxxxxxxxxxx> 
Cc: harp-l <harp-l@xxxxxxxxxx> 
Sent: Saturday, June 9, 2012 5:35 PM
Subject: Re: [Harp-L] How the Turboslide actually works
 
There are many types of SS with substantially different properties.

The #2xx and #3xx types:
- Have a high nickel content
- Have an austenitic structure
- Are non-magnetic
- Cannot be hardened by heat treating.

The #4xx types:
- Have low or no nickel content
- Have ferritic or martensitic structure
- Are magnetic
- Can be hardened by heat treating

I doubt that the presence of magnetic flux changes the elasticity or density of the metal to affect pitch.  Thus the effect must be something more subtle.

If eddy currents in the moving reed reacted to the  magnetic field to cause damping, then the effect would be observed in non-magnetic reeds.

If the magnetized reed were attracted to magnetic material in the plate to increase the restoring force on the deflected reed, then the pitch would rise.  Besides, the plate is not magnetic.

If the moving magnetic flux concentrated in the moving reed caused  eddy currents in the plate, this could damp the reed to affect the pitch.  This seems far-fetched but is the only mechanism that I can think of that allows magnetic flux to affect reed pitch.

Any EEs on the list?

Vern

On Jun 9, 2012, at 12:45 PM, Joseph Leone wrote:

> I'm going to assume the reeds are what 'I' like to call suspicious stainless. Like Dave, I am a MacGiver type. I checked around the house one time back when I was making custom knives. I had been surprised to fine that the stainless that I was working with attracted a magnet. Si I checked in the kitchen and found that 7 out of 8 stainless implements WERE magnetic. Except for out flatware (Ecco), most of my chef's knives attracted a magnet. Some where merely that you could hold the knife in your hand and the magnet would stick with enough flux field to hold the magnet in place. Some were so ignoble that you could hold the MAGNET and the knife would hang there. (To me, that's fairly crappy stainless). 
> 
> Ok, so I found that stuff coming from Sheffield and the U.S. were the least attractive, but stuff from Denmark, Germany, Sweden, Finland, and Japan were VERY attractive. I saw this as a bummer until I realized that (in actuality) you WANT the knives to have more carbon steel than they do nickel and chrome. Why, you say? Well, very good stainless is hard to sharpen well and when it IS sharp, it also looses it's edge quickly. Carbon steel is hard to sharpen but it HOLDS it's edge. So, in conclusion, lesser stainless is actually better for some applications. Now in this case, I think it was to save money BUT we wind up getting the benefit of this faux paux. OR..Brendan does. lolol  
> 
> smo-joe 
> 
> On Jun 9, 2012, at 1:00 PM, Joel Fritz wrote:
> 
>> I'm curious how this works since copper alloys are non-magnetic.  :)
> 
>