Silver tarnish?

[Loren]

I should have asked , in addition , what ,if any , of 19th Century key production do you think was a combination of casting and forging .It is , I suppose , difficult to tell .

I can't say, I haven't stumbled across anything much on the subject. Having said that, I'll hazard a guess:

A highly skilled silversmith could hammer out (pun intended) hand forged keys very quickly indeed. Now, I believe that during the time in question there would have been quite a few top quality silversmiths available in both England and America, and I suspect that having a silversmith on staff doing nothing but keywork, or possibly even subcontractiong the work out to a local silversmith, would likely have been more economical at that time than having someone cast and then heat treat keys, because you'd then still have to pay someone to do the filing and and polishing. So if you had a large shop or small factory making instruments, at that time, it would seem that it would be cheaper to simply hire one person to do hand forging in house, rather than pay for casting, heat treating, shipping, and then someone in house to do the final detail work. That's my guess, but I'd love to find more concrete info on what the makers of old had going on in this area.

These days, a single maker or small shop with only a couple of employees, combined with long waiting lists, and modern casting and heat treating technology, sort of swings the economic edge in the other direction.

Cheers,

Loren
P.S. Andrew, In case you missed it, click back to the previous page for my reply to your first question.

[nopaul]

Cast and heat treated metal is more brittle than forged. While not knowing much about the differences in forging vs casting in flute construction, I do know about the differences in golf clubs. Forged irons have a softer feel and can be bent quite readily while cast peices are very brittle and will break if bent very much. Golf equipment companies started making cast clubs in order to increase productivity. Since we're not whacking things with our flutes, the cast and heat treated should be every bit as good as forged ones.

[andrew]

There are those (and I don't have any view on the matter ) who consider that heat treatment while hardening the metal fails to deal adequately with the granular structure of castings ,which in time leads to failures . That it is necessary to forge at least part of the key to give strength .That is why I was interested in the combination of casting / forging which in my ignorance I suspect some the early key makers used . I am sure they never expected the keys to be in use after 150 years ,rather than a mere generation ,and may well have thaught casting adequate .Even within a business like Rudall & Rose there are huge variations in the quality and style of keywork ,and I suppose there needed to be as the price of different grades varied so much .I cannot believe that the finest of their forged keywork did not take a great deal of time , even when done by experienced " keyworkers" .
It is interesting to remember how the springs have to be worked to harden the metal ,and make them springy and unlikely to break .
As for whacking things you are doing that every time you use a key .You are whacking the pad against the edge of the hole at speed.

[dcopley]

The techniques for hand forging have not changed much over the last 200 years, so a key forged today probably won't be much different from one made in the early 1800's. Over the same time period there have been major advances in casting technology. Vacuum casting and centrifugal casting are standard practices, and eliminate most of the porosity and defects which used to cause premature failure of castings. So the decision to use forged keys would have been a much easier one in the early days, but a close call today.

For ultimate strength and toughness, you would still want to choose a forging process, but casting can come pretty close. The turbine blades in aicraft engines are cast, but the disks they are attached to are forged.

Dave Copley
Loveland, Ohio

[andrew]

Interesting .But what of combination casting / forging ? , Mr C.
Perhaps cast titanium keys are the answer !

[glauber]

I think high-quality stainless steel is even better. But a lot harder to work with!

[dcopley]

Interesting .But what of combination casting / forging ? , Mr C.
Perhaps cast titanium keys are the answer !

Good idea on the cast titanium, Andrew. I had actually made a few enquiries along those lines, but have not yet been able to find anyone willing to make prototypes at a reasonable price. I think that titanium is an ideal key material for its strength, light weight, and corrosion resistance. Pity it wasn't available to the 19th century makers, or I am sure they would have used it. It is hard to join, so attaching key cups would be a problem. The best approach would probably be to cast the key shaft and cup as one unit.

I don't have any experience of the combined casting / forging approach. We have done hand forging starting with silver rod (Marlene is the one who wields the hammer), and also casting followed by a solution treat/age hardening process which gives excellent results.

Dave Copley
Loveland, Ohio

[Loren]

Andrew wrote: "There are those (and I don't have any view on the matter ) who consider that heat treatment while hardening the metal fails to deal adequately with the granular structure of castings ,which in time leads to failures . That it is necessary to forge at least part of the key to give strength .That is why I was interested in the combination of casting / forging which in my ignorance I suspect some the early key makers used . I am sure they never expected the keys to be in use after 150 years ,rather than a mere generation ,and may well have thaught casting adequate ."

Dave has basically adressed this, so.....

"Even within a business like Rudall & Rose there are huge variations in the quality and style of keywork ,and I suppose there needed to be as the price of different grades varied so much .I cannot believe that the finest of their forged keywork did not take a great deal of time , even when done by experienced " keyworkers" ."

Well certainly the highly ornate work would take quite a bit of time, which would make it even less cost effective to cast because the finishing work would be a real bitch, so I have no doubt the high end stuff was forged. On the basic stuff, I really am convinced that a highly skilled silversmith, given the task of doing nothing but making simple system flute keys all day, would be able to crank them out like nobodies business. Let's see, can anyone recall what R&R's average flute output was each year? I think we could work out a reasonable estimate of whether or not 2-3 staff silversmiths could keep up.

"It is interesting to remember how the springs have to be worked to harden the metal ,and make them springy and unlikely to break .
[/quote]

Indeed, I had to make a couple of these as replacements just a couple of weeks ago (and one promptly got damaged in shipping ), but lets not forget that hand forging, by it's nature, does make metal brittle, hence the need for constant anealing during the forging process.

Loren

[andrew]

I lived briefly next door to someone who made stainless steel keywork for silver Boehm system flutes , but I seem to remember that it took him forever .
It would be interesting if there is any evidence of someone knocking out fine forged keys quickly . It is rare enough to see fine keywork of any sort . The only ones I see made seem to take a long time .
I seem to remember that it isn't too hard to TIG weld titanium , but why not make one piece ones ?

[Ro3b]

To polish your silver just use a bit of fag-ash on a finger or cloth and rub away that oxide.

This is a great tip. I tried it just now (with cigar ash) and it worked like a charm.

[peeplj]

I have always been very cautious about polishing silver, especially silver plate, because when you use a conventional polish you actually remove a finite amount of metal each time.

So my question: do any of the modern clothes or polishes pull tarnish off silver by reversing the oxidation, rather than by removing the later of oxide? Is this even possible? I'm guessing this would have to be how the anti-tarnish strips would work if they do much of anything.

--James

[mat]

Seriously James, go with the fag ash. Ive seen it used on 18th century antique silver. Its pretty harmless. I reckon you would have to do a LOT of polishing to do any tangible damage to your silverwork.

Mat

[andrew]

But will your suggestion give a Mat finish ?