Cnc Spring Manufacturing

[Theodore Kloba]

I'm contemplating doing a complete replacement of springs on one old instrument, and I thought about the possibility of using a CNC shop to make the whole set. Certainly they would be a lot more uniform than hand-wound springs. Has anybody ever looked into this?

 

I saw one of these machines in operation at a tradeshow several years ago; it's really interesting: A spool of wire feeds in at one end; mechanical fingers wind the spring and bend on whatever special end shapes are needed; the finished spring lands in a box.

 

There are a couple shops not far from my home, so I may request a quote.

[Bob Tedrow]

I'm contemplating doing a complete replacement of springs on one old instrument, and I thought about the possibility of using a CNC shop to make the whole set. Certainly they would be a lot more uniform than hand-wound springs. Has anybody ever looked into this?

 

I saw one of these machines in operation at a tradeshow several years ago; it's really interesting: A spool of wire feeds in at one end; mechanical fingers wind the spring and bend on whatever special end shapes are needed; the finished spring lands in a box.

 

There are a couple shops not far from my home, so I may request a quote.

 

let me know, I'll take a couple hundred if they measure up.

 

Bob

[Richard Morse]

We have a company that specializes in making springs - which makes ours to our specs - by the ten thousands. I'd be far cheaper to get a set from us (The Button Box) than to go through the time/hassle of getting a shop to get a set "right". There are a lot more variables to spring making than one would think.

[Theo]

I asked a local spring maker about making concertian springs. I can't remember the exact details, but there was a setting up charge of 50GBpounds and an additional minimum order of 50GBpounds so its only worth doing if you need large quantities.

 

Then as Richard says you need to get the specification right, and there are many variables.

[JimLucas]

...as Richard says you need to get the specification right, and there are many variables.

And it's not just an issue of getting "the one" right set of variables.

 

I have a small supply of spare springs that I got from Steve Dickinson some years ago. He supplied me with three different grades: "light", "medium", and "heavy".

[Theo]

...as Richard says you need to get the specification right, and there are many variables.

And it's not just an issue of getting "the one" right set of variables.

 

I have a small supply of spare springs that I got from Steve Dickinson some years ago. He supplied me with three different grades: "light", "medium", and "heavy".

 

And there is left and right handed (most concertinas use both) steel, brass or phosphor bronze wire, diameter of coil and number of turns, both affect how the spring force increases with more button movement, length of each arm, and more...

[Theodore Kloba]

It'd be far cheaper to get a set from us (The Button Box)

I should have said: These springs are for a bandonion, so the shape is different from concertina or accordion springs... In fact, it's even different from the vast majority of bandoneon/chemnitzer springs, since it's a very old bandonion.

there was a setting up charge of 50GBpounds and an additional minimum order of 50GBpounds

Was this a CNC spring shop, or a more traditional maker? I'm sure nobody likes to deal in tiny quantities, but there shouldn't be as much of a setup fee for CNC as for traditional. I'm sure it also depends on how complex the ends are. In my case it's just an ell on one end.

And it's not just an issue of getting "the one" right set of variables.

On this instrument, all the springs are the same.

And there is left and right handed (most concertinas use both) steel, brass or phosphor bronze wire, diameter of coil and number of turns, both affect how the spring force increases with more button movement, length of each arm, and more...

All easily measurable in this case. So I guess it's just a matter of getting a quote.

 

FWIW, these are the two shops I might try:

http://micromaticspring.com/

http://www.internationalspring.com/prod03.htm

[Theo]

QUOTE(Theo @ Jun 21 2006, 02:47 AM) *

there was a setting up charge of 50GBpounds and an additional minimum order of 50GBpounds

Was this a CNC spring shop, or a more traditional maker? I'm sure nobody likes to deal in tiny quantities, but there shouldn't be as much of a setup fee for CNC as for traditional. I'm sure it also depends on how complex the ends are. In my case it's just an ell on one end.

 

No I think they are a traditional maker. I'm interested to hear how you get on.

[Chris Drinkwater]

No I think they are a traditional maker. I'm interested to hear how you get on.

 

Many years ago, I came across a traditional spring makers not far from where I live in North London. They were using treadle operated machines and appeared to be able to make any kind of spring you wanted, provided you supplied a pattern, in any quantity from a one off to a few hundred. I recall that they specialized in car brake springs and I got them to make me up a set of new brake springs for an old Morgan three-wheeler I used to own. That was in the days before I acquired my first concertina. Sadly, they have long since gone, as have many old trades, such as my local blacksmith. Guess there are not too many inner city horses around these days. Anyone know where David Leese gets his springs made?

 

Chris

[Frank Edgley]

If you can get the right size wire and number of coils, in the right material, it's not necessary to worry about length of the arms, or the end configuration. These (the ends and arm length) are surprisingly easy to do.

[Theodore Kloba]

If you can get the right size wire and number of coils, in the right material, it's not necessary to worry about length of the arms, or the end configuration. These (the ends and arm length) are surprisingly easy to do.

Certainly, they're easy to do, but if it costs not much extra to have the machine do it (likely with CNC), why not?

[Frank Edgley]

Well, if you're only doing one, it's only 30 or so springs for and anglo etc. etc. By not having the ends done for you, you can decide whether they're right or left handed, and the arm length. It takes about 15 - 20 seconds to do it yourself. ---only a suggestion...