A A spring, even when only wound partially stores a great
deal of power and MUST be treated with every respect or serious personal
injury can occur.
B Most clock springs are thin flat strips of special
steel with a hole at each end and are fitted into a BARREL. Others have a
hole at the inner end and a loop at the outer which hooks over a pillar and
are generally open and visible.
C As the spring is wound the CLICK system prevents it
uncoiling.
D The hole areas are by their nature and position weaker
than the body of the spring.
E Springs often, but not always, break at a hole.
F There is NEVER any warning!!
G The violent release of energy and the reverse thrust
set up when a mainspring breaks almost always causes some damage to the
teeth on some wheels and pinions. Whilst closed springs remain in the
barrel, open types can often fly outwards.
H If the CLICK system fails to work the full power of the
mainspring is released. This usually happens during winding and results in
the key revolving backwards at extreme speed and with considerable force. This
is the moment when the operator is at greatest risk of personal injury and
he or she should be aware of this at all times.
I ALL springs can break; even a NEW one on the first
winding.
J During repair you will be informed if springs show
obvious weaknesses or if their anchor points are damaged. In addition, all
click springs, ratchets and pawls will be replaced if they appear in danger
of failing. HOWEVER, MOST METAL FATIGUE IS NOT VISIBLE!