Spring Time

[John Delacour]

At 11:27 -0400 16/4/08, Jon Page wrote:

>I made a few springs by hand with a hinge pin mounted in a vise to form
>the coil but am interested in what is a suitable spring making tool. Possibly
>the one listed in the Schaff catalogue or someone's fabrication. Ideas? Pix??

I've had ready-made spring tools for years but never found a use for 
them.  I make all my own springs except for a few types and make a 
tool specially for every type of new spring.  I'll take some pictures 
but the idea is simple.  Get a piece of 1/2" or so hardwood and make 
a hole in it to hold a 6" length of hardwood dowel.  Glue the dowel 
in the hole with the end flush with the top surface and screw into 
its centre a screw the size you need to get the coil diameter you 
want.  Saw off the head and file the top smooth.  You can also file 
down the circumference of the shank to get just the diameter you 
need.  To get the shape and curves of the spring, use centre pins, 
washers, larger screws etc. and play about until you have things just 
right.

>Also, I'll be making different wippen assist springs. The arm which attaches
>to the loop is too short and strained at rest. I've done some experimentation
>and found that a longer arm has a more fluid feel to it's affect and there is
>less of a tension change from rest to full key stroke. And according to
>Ron O, they need an extra coil.

Many piano springs are over-strained and an extra coil, where there 
is room, will extend their range and life.  Upright damper springs 
are always over-strained, for example and always need to be replaced 
on old pianos.  Last month, by chance, I came across two 100 year old 
uprights with actions by makers who had given the damper springs 3 
instead of 2 coils, and the springs are as good as new.  You need to 
adjust the gauge of the wire to get the required pressure, but there 
is a net gain from more coils.  In the case of helper springs, such 
as you are making, there is very little movement and the risk of 
breakage is low compared with damper springs, butt springs etc.

JD