[CW] Changing Sprngs

[Bill Cromwell]

Hi Richard,

Some of those "hairpin" springs have a loop at the back and some are 
just folded with no loop. They have been used a lot as stationary 
retainers as well as return springs. They are use under the keys on my 
accordions and I think most pianos. With multi-turn loops at the back 
you will find them in mouse traps. Much heavier ones without a loop at 
the back are on bear traps.

And then there are torsion bars... "let's do the twist".

73,

Bill  KU8H

On 01/23/2018 10:39 PM, Richard Knoppow wrote:
>     I was catching up with unread messages and found an old one about
> replacing a spring in a key.  I have made springs for keys many times
> where the original spring was missing. The first time was when I was in
> my teens and managed to loose the spring from my brand new J-38. Well, I
> made one from the spring in a ball point pen. I discovered my makeshift
> spring (its still in the key) changed the feel entirely. The original
> felt "spongy" and much more recently obtained J-38s have the same feel.
> The home made spring felt crisp. I am not sure what causes this
> difference, its not the strength of the springs since the compression of
> both for the same pressure was about the same. I have since made springs
> using spring stock from the hardware store for a number of straight keys
> and a TAC bug where the dot return spring was missing. All these keys
> have the same sort of crisp, positive feel. One difference I notice is
> the thickness of the wire. The J-38 keys have rather thick wire which I
> read somewhere was either beryllium copper or phosphor bronze, can't
> remember which. The springs I made are all from spring steel. The first
> two have the advantage that they do not corrode. Whether its the
> material or the thickness something makes a difference.
>     Something else I wonder about. Photos of some very old keys show a
> different spring design than the familiar conical helical springs, these
> are sort of like the spring part of a safety pin with an extension going
> to the pressure adjusting screw and the other end going to a hole in the
> frame of the key. I have at least one of these keys, an E.S.Greeley key,
> that from its catalog pictures had this kind of spring originally. The
> original spring was gone when it was given to me so a made a
> conventional spring for it. This key, BTW, from the address on Dey
> street on the stamped in label is c.130 years old, probably the oldest
> object of any sort I own. I am curious if some of the real key
> collectors on this list have keys with this sort of safety pin spring on
> them and can they comment on how it affects the feel of the key.

-- 
bark less - wag more