The spring is called a buckle spring.
In its actual use, it is "L" shaped with the top of the
"L" restrained by a notch in the button shaft, and the
right end of the "L" restrained by a notch in the key
switch frame.
Its purpose is to sit in an "L" shape, holding the button
in the full up position, until the button is pressed hard
enough, compressing the top of the "L" until it causes its
bottom of the "L" to buckle.
When the spring buckles, the button quickly drops down, and
causes an internal contact to make.
Another way to visualize it pressing on the button causes:
L -> h
It is not a contact, just a spring. It is 0.0022" thick,
measured with a Starrett ten thousandths micrometer.
It is made of spring steel... just like a feeler gauge.
There have been dozens of posts on the subject on this
group... some of them even by me. Try searching.
-Chuck Harris
On Thu, 03 Jun 2021 08:33:22 -0700 "Jim Adney" <jadney@...>
wrote:
This comes up often enough that it would be useful for someone to
actually measure one of those pieces with a micrometer. McMaster-Carr
sells individual feeler gauge 12" strips in almost any thickness. I
just happen to have some .002" feeler stock that I've already cut up
for another purpose, in case that's what is needed, but I suspect
what's needed here is thicker.
Is this spring part of the electrical path? If not, spring steel,
often called "blue steel" would be a good choice. This is also
available from M-C in lots of thicknesses.
If someone would measure and share the L, W, & T, replacement springs
should be easy to make. Thin stock can be cut with scissors.
