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

[Vern <jevern@xxxxxxx>]

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.  :)
> 
>