I'm repairing an old musical instrument and need to replace 4 small
Measuring one of the unbroken springs gives: wire diameter 0.5mm, 2 1/4
turns, inside dimeter 3.5mm, one arm about 22mm with 2 small bends in
it, the other arm is about 11mm with 1 bend.
I'm planning to take a naive approach and simply wind some piano wire
around a 3.2mm mandrel, add the bends and then bake it at 250C for an
hour or so. Will this work? How do I hold the start end against the mandrel?
Winding a spring from piano wire of the appropriate diameter should do the
trick, it is unlikely that you will need to heat treat it. Do not try to b
e too economical with the initial wire length. Use a long enough piece to
get a good hold on it at each end and try to keep some tension on it as you
wind it. There are a number of designs of spring winders marketed to the
instrument repair trade. While not worth buying for 4 springs, looking at
the instruction pages for them might give some clues for your application,
try having a look at Votaw Tools springwinder which has a video and manual
for their tool: http://www.votawtool.com/springwinder.html . In the UK you
can buy spare parts for many instruments from Dawkes Music http://www.dawk
es.co.uk/index.php. They list springs and spring wire under repair materia
ls and formed springs under spare parts. Their site has good pictures of t
he spare parts so if your particular brand/model isn't listed have a look a
t other makes to see whether there is something that looks similar that mig
ht be adapted. I have always found them to be very efficient and helpful.
need other items such as reeds, lubricants or cleaning brushes if you deci
de to place an order with them.
On Sunday, January 4, 2015 9:07:01 PM UTC, no firstname.lastname@example.org wrote:
Thanks for the reply. The instrument is an old East German Melodeon so
I'm resigned to making the springs. The video at the votawtool link
makes it all look as simple as I had hoped.
I thought heat treating was needed to remove stresses and reduce the
risk of failure ... but that's based on very hazy memory.
On 05/01/2015 11:08, Brassman wrote:
On Monday, January 5, 2015 12:30:32 PM UTC, no email@example.com wrote:
I see that this company specialises in accordion/melodeon parts. Might be worth giving them a call. I have no personal knowledge of them though.
I just have a hole in my mandrels, but that wouldn't work for the
arms. What about just tapping a small hole in the side of the mandrel
for a screw? Might make a washer shaped to capture the wire if needed.
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