Brass or bronze?

Do you think the shank of a tuning key can be made in brass?

Years ago I made one, I gifted somebody I don’t remember so I can’t ask him how is it behaving. I am afraid of the torsion if the tuning pin is too tight in its hole. Can a tuning pin possibly sit so tightly in its hole a brass tuning key shank twists or even breaks?
Or should I try with bronze? (I don’t like iron nor steel) Of course I tried that tuning key but I only turned a few wrestpins so I can’t say for sure it’s safe. I have never seen a brass shank tuning key, only steel or bronze, this is why I am asking.

Here is how I did it (sorry I haven’t any photographs), and how I am thinking to do again.

A turned wooden handle with a hole diam 8 mm (0.315 in). A brass shank that goes in that hole with a very snug fit, maybe reinforced with epoxy (I didn’t use any glue or epoxy back then but am thinking about using it now). A brad nail diam 1.6 mm (0.063 in), in the wide face of the handle, through the brass shaft.
At the other end of the shaft: sawn/filed slot for the tuning pin head. Last 20 mm (0.78 in) covered by a tube internal diam. 8 mm, external diam 10-11 mm (0.39-0.43 in).
All in brass safe the handle which is in wood. I took these sizes from other working tuning keys such as the Vogel’s (photograph attached).
What do you think? Am I sure enough with brass or should I go with bronze?

Of course all of you know how a tuning key is, but I attach a photograph of one similar to mine (this is from Carey Beebe website, CBH Carey Beebe Harpsichords Australia — Global Harpsichord Technology. You can see the wrestpin end of the shank here better: CBH Customizing the tuning hammer fit, I used the same method.

image

Why exactly don’t you like iron or steel?

I have not seen brass tuning hammers but while I initially thought on reading this that brass would be too soft for the head, I then came across this:

Observe though this has a steel shank.

The other comment I would make is that if your historical tuning pins are in so tight that the hammer is likely to break you have rather bigger problems!

Dear Domenico

No.

Brass, of course, being softer, is far easier to machine than steel. But that also means it lacks strength and wears far too rapidly to be considered useful for a tuning hammer. A sloppy hammer is next to useless for quick and accurate tuning.

David Law’s beautifully-made hammers of several sizes are cast in bronze, a much harder material.

An advantage of a slot cut in the end of steel shaft and sleeved, however, is that the sleeve can be temporarily removed and the slot filed to suit any pin profile before the sleeve is refitted—as my movie you kindly mentioned shows.

For me, the hook of the HCH hammer is 90° out of alignment: That might be perfect for hanging the tuning hammer on a nail, but it prevents the hook fitting comfortably between the fingers when actually tuning.

Tight tuning pins are another problem, as Andrew mentions. It is entirely possible to shear the top off a pin held too tightly or even corroded in the wrestplank, especially if the pin has a hole supposedly to facilitate stringing. (Another instance of a modern “improvement”.) And yes, I have heard of a tuning hammer separating from its handle or twisting itself asunder instead of rotating the over-tight tuning pin.

Regards

Carey

Andrew, Carey,
Thanks a lot for your insights. I haven’t too tight pins, I was only asking just in case. I’ve thought of the possibility of twisting but not of the wearing of the slot, so Carey thank you for having mentioned it.

I know David Law’s tuning keys, and I have ordered one. Don’t even think I could make something so beautiful, I am trying just because of fun, as I have a lathe and am learning how to use it by making some wooden handles.

Andrew, I just don’t like iron and steel color, it’s just an aesthetical preference.

So, no brass. I’ll try with bronze. I’ll let you know if I succeed. By the way, is bronze workable with ordinary files, drills and hacksaw?

Dom

I dont know the bronze tuning hammers by David Way, but I have two of the standard ZHI steel hammers, the advantage of which is that they can indeed be used as a hammer to seat a tuning pin. The hooks unscrew and might easily be reset to a preferred angle.

However, my favourite tuning hammer was made by David Jensen. It has a wooden handle 175 mm long and a round mild steel shaft held into the handle by a pin. I imagine that it was hand-made, by cutting 5/16" steel stock to length, drilling it for the pin, and sawing and filing the slot for the business end. The final step was fitting a brass sleeve that prevents the slot from widening.

I agree with others that there is something wrong if much force is required to tune a well-made harpsichord. I hold either tuning hammer lightly between the fingers, as otherwise it is impossible to achieve the necessary precision. As I have large hands, I find the Jensen hammer more comfortable, but I use the ZHI one when stringing.

I have an earlier (and less expensive) iteration of the HRH tuning
hammer. It’s all brass, no steel. I’ve been tuning for a decade and a
half with it and there’s no noticeable wear in the slot. I’ve just been
tuning a clavichord, though, so maybe once a month on average (I’m
making this number up), not exactly heavy-duty use.

I’ve also used it to make loops for the occasional repair (mostly for
other people’s harpsichords) and also never noticed that the angle of
the hook isn’t optimum. Now that Carey Beebe has pointed that out, I
expect that I will have trouble making future loops. In the past,
though, I’ve found it very comfortable because it weighs so much that
there’s a lot of momentum when it’s spun around. I really like it for
loop making.

best to all,
Stuart

Stuart, are you sure it’s brass? If you are not sure it could be bronze. I am looking around on metals and finishing these days and learned there are dozens of different bronze alloys, some of them resembling brass in colour and texture. (I am embarassed in speaking of metals in a forum where one of the users is Philip Birkett! Please forgive errors)

Brass is an alloy copper + zinc. The yellow strings we use are usually 70% copper and 30% zinc. The red strings in the bass are 90-10 (this can be not the case with Birkett’s brass, I don’t know).
But if you add a small percentage of lead (3%) you gai greatly in machinability.
If you want harder brass you add phosphor. And so on.

Bronze is an entire world. Dozens of different alloys: copper and tin is the base, then manganese, nickel, lead, phosphor and others in various percentage. The colour, hardness, machinability, change dramatically. We have manganese bronze, phosphor bronze, silicon bronze and so on, each of them are in fact various alloys. The only way to not be confused is to use numbers.
Silicon bronze (bronze 655) is reddish (high content of copper), others are yellow, quasi-gold, others brown etc.
Then there is the “commercial bronze”, aka bronze 220. Remember: brass is copper+zinc, bronze is copper+tin. But the bronze 220 is copper+zinc+tin. So it’s a brass because the zinc percentage is superior than tin.
Only a few of the bronzes: The Online Metals Product Guide | OnlineMetals.com®

By the way, as Carey pointed out, David Law’s tuning keys are silicon bronze, it’s very beautiful. I found a forum where someone said it’s one of the most machinable. I’ve tried to locate silicon bronze 655 rod diam 8 mm (5/16’’) but didn’t succeed. Nobody in Europe. I found only two suppliers in USA willing to ship to Italy but asked something like 35$ for the material and 280$ for the shipping.
If anybody can point me to an European supplier, please tell me.

Following Carey and Andrew advice, I abandoned brass (though Stuart’s post is encouraging) for steel (maybe silicon bronze if I can find it). I am experimenting with chemical blueing/rusting and heat coloring. I am not satisfied so I asked a quote to a electroplating factory. I think of trying with brass and pink gold electroplating. At the very last I’ll have the tuning pin shaft nickeled or chromed, just like the Marc Vogel tuning keys.

Sorry for the length.

Dom

Ah! This is the worst! Sorry Stephen.D

Domenico, try to find a friend near the source of those metal rods who is willing to cut them to manageable length and send them to you in a USPS flat rate box. The medium box goes for under $60 and the large box is under $75, if I remember correctly. Both rates will ship up to 20 pounds of stuff from the USA to Italy.

https://www.usps.com/international/priority-mail-international.htm#flatrate

Hi, Dom -

I’m pretty sure it’s brass. My father was a metallurgist but his skills
weren’t genetic. On the other hand, I’ve seen a lot of slabs of bronze
and the occasional brass in my other-music life with Javanese gamelan
(mostly bronze but occasional cheap, and terrible sounding, instruments
in brass; the usual cheap instruments are iron). The color of the tuning
hammer looks like brass to me, not like bronze. It’s all of the same
material. Of course, there are bronze alloys that look pretty much like
brass, so that’s not proof.

If I remember correctly, it was sold as “brass” but my memory is fallible.

I don’t have a mass spectrometer handy to test (I did try building one
as a weird project a long time ago. It never really had any hope of
succeeding because there’s no way I could have drawn a high enough
vacuum. It would have been only for volatile organics, anyway.)

Oh, maybe x-ray fluorescence would work. Checking ebay … looks like
you can get a refurbished spectrometer for something in the
$10,000-$15,000 range.

It’s not my birthday, so that’s no good.

Checking aliexpress. Ah, there’s something for only $3000. The top of
the page describes a spectrometer, and the bottom of the page describes
a centrifuge. The listing does not inspire confidence.

That’s about as far as I know how to take this.

best,
Stuart

Hi Stuart, reading up on how to tell apart bronze and brass alloys when it is doubtful, one site mentioned that many scrap metal yards have X-ray fluoroscence machines, for obvious reasons. Buy your local metal dealer a beer.

You can make steel a lovely rich and durable black by heating it in linseed oil. Very non toxic and a lovely effect. There are lots of pages on the web about this old technique. Maybe you would like that?

Bluing can look very beautiful - think of the superb blued steel hands on 18th century English watches, and indeed still today.

Yes Andrew, I’d like that. I am now playing with the chemical blueing used on the guns. After I’ll try heating and quenching in oil.