14 replies to this topic

[Jack Zuraw]

As far as I know, even replacement reeds in old brass-reeded instruments are either made of steel or taken whole from another old instrument.  I myself have made a few brass reeds individually by hand, but the brass sheet I used was made specially for me by a craftsman friend, using a formula for "reed brass" from a 19th-century book.

Jim,
This probably should not have been in the Buy-Sell forum ( http://www.concertin...p?showtopic=282 ):
What is the 19th century formula (approximately)? Is it like Phosphor Bronze? Was the sheet rolled to spring temper?
Jack

[JimLucas]

As far as I know, even replacement reeds in old brass-reeded instruments are either made of steel or taken whole from another old instrument.  I myself have made a few brass reeds individually by hand, but the brass sheet I used was made specially for me by a craftsman friend, using a formula for "reed brass" from a 19th-century book.

Jim,
This probably should not have been in the Buy-Sell forum ( http://www.concertin...p?showtopic=282 ):
What is the 19th century formula (approximately)? Is it like Phosphor Bronze? Was the sheet rolled to spring temper?
Jack

What's the "smiley" for a puzzled expression? I thought I had answered this question already a while back. Well, maybe not.

I lost touch with the fellow who made the brass many years back, and I have no idea what the formula was. I have no idea how close it might have been to original concertina reeds, and I'm sure there have been many formulas for reed or spring brass over history, just as there are for spring steel. Nor do I know what sort of tempering or other processing he used, except that he rolled the brass into small sheets. The thickness ranged from standard reed thickness to about double that. The thinner stuff seemed to be more "spring tempered" in behavior.

I do have a little left, so if there's anyone here with the laboratory facilities to compare chemical and physical composition between that and an original reed, I might let them have a little. But I'll be very restrictive about that; I don't want to waste it on somebody who has the curiosity but not the analytical capability. (How about convincing me by sending me your analyisis of an actual brass concertina reed, first?)

In the meantime, I might suggest that anyone interested in making brass reeds, if they can't find a modern maker of spring brass, should look in university technical libraries for 19th-century books on the subject.

[David Barnert]

What's the "smiley" for a puzzled expression?

:-/

As I type this, I have no idea whether the glyph above will be replaced with a "cute" yellow dot, so I will describe it as a colon, a dash, and a slash (forward or back will do, this one's forward).

[chris vonderborch]

Modern phosphor bronze makes excellent reeds; I have used it to replace broken brass reeds. Incidentally, I find it virtually impossible to tell it apart in sound from either brass or steel reeds. Which begs the question: how do instruments, such as some Wheatstone Aeolas (even baritones) produce that lovely muted tone?

[Jack Zuraw]

Chris,
What temper stock and what starting thickness did you use? I have made two replacement reeds for a 26b Lachenal from 'thick' phos bronze of unknown temper, and they seem to work fine. I'm wondering about their long term performance...
Jack

[Alan Day]

Hallo Jack,
From my purchasing days in the metalworking trade ,I seem to remember that the brass sheet suppliers sell brass in three hardness types,Hard,Half Hard and soft.
The hard beng the one you would want about 20swg.
Regards
Alan

[chris vonderborch]

Jack, I am unsure of the specs. for the phosphor bronze; it was handed to me as a scrap piece from a now extinct engineering shop. If I recall correctly, it was about 0.6mm thick.

[Alan Day]

A good tip for hardening brass is to gently hammer the suface along it`s
length.I found this usefull when buying some brass wire for springs which did not spring and by gently hammering along the length of the wire, it became hard and springy.I cannot remember the technical reason why this hardness occurs ,but I think it was to make the molecules all face in the same direction.It is part of work hardening which is unfortunately the reason why brass reeds eventually become brittle and snap off.
Regards
Alan

[Clive Thorne]

This is a form of piening (spelling?), which is actually making a minor come back as a commercial method of surface hardening, although in commercial processes it is (I believe) done by a form of shot blasting.

Clive

[Jack Zuraw]

I know that jewlers use a 'rolling mill' to achieve similar effects, but in softer precious metals. My posphor bronze is 1/8" thick and I've tried hammering small pieces out to about .5mm before sizing and filing the reeds. Too random to be scientific, but it is interesting to consider how this might compare to the original 'copper alloy' reeds.

[JimLucas]

I know that jewlers use a 'rolling mill' to achieve similar effects, but in softer precious metals.

Well, compression rollers (probably what Jack called a "rolling mill") are what my friend used when he made the reed brass for me. He rolled it repeatedly, making it thinner on each pass. With each pass in the same direction it should have a similar effect of stretching and aligning crystal domains.

[Dave Prebble]

Hi All,

'Spring grade' brass and phosphor bronze strip are, I am sure, still in use today and most likey in sizes suitable for reed making.

A spare hour or so with the yellow pages and a phone, and a little of the 'gift of the gab' should produce some results from specialist spring manufacturers, either in the form of raw materials or as ready made springs that can be tailored to suit.

A similar quest provided me with two coils of different diameter phos bronze spring wire.... enough to make thousands of lever springs....

Seek (hard enough) and ye shall find

Regards

Dave

[d.elliott]

Hi Dave,

Glad you are back! Its good to have your experienced Engineer's input.

What about the brass/ bronze spring material used for making the arms on electrical contactors? or is it all solid state these days?

Dave

[Alan Day]

I agree welcome back Dave.
Al

[Dave Prebble]

Thanks Guys, nice to be back!

Dave Elliott <What about the brass/ bronze spring material used for making the arms on electrical contactors? or is it all solid state these days?>

I must admit I was thinking more in terms of springs for use in instrumentation or gizmos & gadgets in general, but as you rightly point out, electrical switchgear contactors would require similar 'spring' properties and, who knows, reeds made from such material might just have that extra little spark! ;-}

Dave

Afterthought.... electrical grade material might also contain a lower level of impurities and possibly be less susceptible to fatigue ??