A metallurgical prospective on watchmaking

[Ophiuchus]

Considering the high company among this site, I was loathe to post a question of my own. I speak here among watchmakers both novice and famous, and I am not one myself yet.
I also don't wish to drag this forum down to something more plebeian, nor do I consider people here royalty. The mere fact that I can, as a citizen, ask questions of watchmakers
and famous independents, is quite humbling and inspiring. So I'll just ask and see who answers.

Everyone passionate about horology knows the metals of a modern watchmaker. My question is, what specific alloys do those who come here use? I'm familiar with many metallurgical compositions,
from the so-called german silver varieties, to the alloys of gold Breguet himself used in the springs of his Sympathetique clocks. I've searched exhaustively over the years for these things.

What alloys of brass do you use in your watches, and for what parts? Are there specific alloys of brass that are set for watchmaking, or right out should never be used?
Even beyond brass, what metals do you use for your gears, pinions, balance rims, weights, and any other key components? Perhaps I've asked something too secret to be revealed...

The reason I ask is genuine curiosity, and that lately, I have a chance to buy a large amound of good Alloy 260 Brass plate stock with a metallurgical report. Until recently, I considered actually attempting
to make a watch something doable, but something I would only attempt after I received training at a school for watchmaking. Anything short of that would be sheer hubris. Now, I've decided if I wait for training,
I may never make a watch. The very act of making a watch is somewhat an exercise in hubris, no matter what training you have, because doing so, you are training yourself anyway.

I've interviewed at two of the top watchmaking schools in the US within the last 2 years, and to get that far at both tells me I can do it. But I need to improve my skill.
I go at things the hard way. Perhaps if I make even a time only watch, I will have progressed to a level where the remaining schools I'd like to join will take me a bit more seriously.
Not that the ones I have been to have not- I know I've impressed them at both places. I didn't get into these "Harvard or Yale" of watchmaking, as it were, but the fact that I got to the final interviews emboldens me.
I also know I'm not crazy, but to make a watch is a bit crazy for anyone. I know I'm crazy enough to succeed with enough time! I can only learn from this endeavor, even if the result is poor.

I risk sounding laughable stating that, but I have the time outside my job, and I have many tools already. Metal stock is my concern now. And those who have posted here, along with men like Daniels,
have shown me it's possible. I just need to approach this methodically, and patiently. With a year or two of spare time!

What alloys should I be looking at buying for this? Would some of the more famous among us care to comment on this, or what alloys they use?
If I've asked something taboo, I apologize.

I have no intention of becoming the next Daniels, Sarpaneva, or anyone else. I am just a passionate soul who wants to make a watch, for my own sake and skill. I don't care about becoming famous or rich.
I simply enjoy the concept of someday wearing on my wrist a device of my own making that tells the time as I alone intended. That's enough for me. I am tenacious, patient, extremely mechanically inclined,
and eternally curious about the smallest things. And if I can't yet get training, perhaps it's time to train myself!

I'll leave you with a fantastic article for those curious about the gold alloys used in watchmaking, as my contribution of knowledge for the thread:
http://www.goldbulletin.org/assets/file/goldbulletin/downloads/Trueb_1_33.pdf

[Ophiuchus]

I'll also add I know that 260 Brass doesn't take a shine as well as 360 Brass, but does anyone here use 260 brass in any of their work?

[Paul Loatman]

Bras 360 is good since it's readily available and it has very good machineability, but i've used 356 brass that's mostly sold in large quantities but it seems to machine a bit easier, probably because it has a bit more iron in it. If you can afford full sheets and rods then go for it.

As far as pinions and springs and any sort of steel bits that needs to be strong use some sort of oil or water hardening tool steel. W1 and O1 are very good for pinions and springs, O1 is oil hardening and W1 is water hardening, however if you get Parks #50 oil then you can harden the W1 in that which is safer for the steel than water and is specifically made for steels that are normally water quenching. Never use a tool steel that's air hardening because it's just way too complicated to harden and will require a furnace.

Never use mid or low carbon steels for pinions, staffs, springs, or steel levers. A mid carbon steel like 1045 to 1060 would be good for stems however you shouldn't use a tool or higher carbon steel because it's very difficult to cut threads onto a tool steel unless you use a special lathe that can cut threads. I've also used 416 alloy stainless steel for stems and screws, i really like 416 for making screws, it's a lot easier than a regular steel because it's more malleable and in small sizes a normal steel tends to be more brittle and might break inside a screw plate.

I've been working with metals most of my life though so it mostly takes experience to get to know different alloys since not everyone likes to use the alloys that i use. I used to work a lot with Japanese swords and the hardening processes of Nihon-to are much more complicated than watch parts, watch parts are just hardened like a spring almost always, whereas a sword would be a single solid object with two different levels of hardness. So when i first hardened steel for a staff at my school it was like childs play.

You can make an entire watch with just brass and steel though, usually just 3 different alloys, one for the brass plates and wheels, another for steel parts that need to be strong; springs, staffs, pinions, etc. and another for screws and threaded parts that don't need to be very strong but could be made with a corrosion resistant steel, which could also be used for the case if you can't afford gold or any other precious metal.


Also, to add, you don't really need to go to a watchmaking school to make a watch, if you have good mechanical and machining skills and a good understanding of what a watch really is then it's just a matter of time, as long as you think of it as something that you have all the time for than you can get through any difficult task in making a watch, just think of every part your making as something you might have to throw away and make again.

[David Walter]

Paul has given a good reply, I would certainly avoid 260 brass even it is a bargain, 360 is much better to work with and you can buy smaller quantities, for plates and bridges I recommend 356 which is free cutting.

For steel, use O1 tool steel which is readily available in a vast assortment of sizes and drill rod for rounds, from which pinions can be made, a much better choice if you can get is Sandvik 20AP steel which is an oil hardening steel and is superb for pinions.
Do not use low carbon steel for screws, if you do you will never be able to polish the heads to a black polish and the softer steel will stretch, use O1 steel, harden it then finish it as you wish.
German Silver is a good choice too as there is no need to plate it after finishing, it will accept any finish you wish to apply but I find it rather "sticky" to machine and thread. I believe Dufour uses German Silver for his plates and bridges.

The important thing here is your desire to make a watch or at least some parts of a watch, please don't obsess about materials as there really is little choice and those choices are available and waiting for you to start cutting metal.

David

[Ophiuchus]

Thank you both for your responses. I found a good source of 360 Brass, unfortunately for now without a material report. While I love the look of German silver, I've read that it easily stains by even the oil of the skin, lubrication oil, and such. I think my first watch should be done in a traditional material, brass, and I was thinking of gilding it gold. Mainly, I want to do brass because I feel working with it will improve the most immediate skill I need- that of file working and turning brass. Once I learn to work with the most traditional metal, and I've convinced myself I'm good enough to risk it, I may try a crucible powder stainless steel for my baseplate, or white gold, if I can afford it. I would love to use German silver, as I love the way it finishes, but the staining issue bothers me. I haven't decided yet.

I've also entertained a really wild idea of using iridium/osmium alloy for my gear train, the same that fountain pen nibs use, for maximum tooth longevity. It would be a challenge to work with, as it is toxic, but my eventual goal is a watch made of specific metals that allow for maximum longevity, even submerged in seawater. I can't make something that will last forever, but I can make something that will last a very, very long time without degrading. It's always bothered me that even the brightest works of the brightest men in one century can, through neglect, deteriorate so badly after only 200 years or so.

[ASWatch]

Just to offer up a simple - obvious even - solution to what seems to me your greatest doubt regarding German Silver, staining: rubber gloves / finger cots. If you need to handle the finished parts with your hands, use protection!

Brass and steel (yes, even stainless) will also stain surprisingly quickly at the mercy of sweaty palms.

Must admit though, all these exotic materials do sound interesting.

[Ophiuchus]

I have a question for you specifically, David- in reading Loatman's thread, you sugguested the same 353 brass to him as well. I read up on the stuff, but it doesn't seem to take as nice a shine as 360 brass.

Can you elaborate a bit more on why you recommend it, what you use it for, and where I can buy it conveniently? The stuff seems hard to find.

I know more about gold alloys in watchmaking than brass, can anyone comment on if there was a traditional mixture for brass in clock & watchmaking over the centuries? My guess is no, but I could be wrong.

[Paul Loatman]

I have a question for you specifically, David- in reading Loatman's thread, you sugguested the same 353 brass to him as well. I read up on the stuff, but it doesn't seem to take as nice a shine as 360 brass.

Can you elaborate a bit more on why you recommend it, what you use it for, and where I can buy it conveniently? The stuff seems hard to find.

I know more about gold alloys in watchmaking than brass, can anyone comment on if there was a traditional mixture for brass in clock & watchmaking over the centuries? My guess is no, but I could be wrong.

I can't answer with the specifics, but a popular application use for 356/53 is clock plates, and that would also count for watches, it's known for it's horological use. It's also a much simpler alloy than 360 and that might mean it's more traditional.

As far as finishing goes, they look identical to me when polished.

Read the material data here; http://www.matweb.com/search/DataSheet. ... 8a91946d4b

Compared with 360 here; http://www.matweb.com/search/DataSheet. ... 6641162def

[Ophiuchus]

Paul, thank you for the direct comparison. I checked the data sheets- they are very, very similar. It must have been the so called "engravers brass" (353/56) that was indeed used mainly for clocks & watches over the ages.

If I want to be more traditional, I can, but to me, their metallurgical compositions are so close in Copper & Zinc ratios I feel either is appropriate.
My main concern now is sourcing large amounts- I have clocks I wish to build as well, and finding any source of 353 or 356 at a fair price in large size is a bit daunting. McMasterCarr carries 353 in a very narrow size range, and for brass, that particular type is absurdly expensive. It would be cheaper to smelt my own at home in a crucible, really- they want 1400$ or so for a 0.5" thick 24x48" piece- just one! That's flabbergasting. 360 can be found elsewhere fairly easy, and is far, far cheaper.

While brass can be sourced from many places, as well as gold, when we get into things like German silver, who retails that? I've never found anyone. I know various metallurgical makeups for the stuff, so I could technically make my own in a furnace of my design rather inexpensively, as I imagine the makers of Saxon did over wood fired furnaces and whatnot.

Any ideas if I went the route of German silver then?

As for Iridium, that's an even harder one to source, especially in the native iridium-osmium alloy that is found naturally occurring, which happens to have the best mechanical wear properties for gears, I feel. It must sound absurd to mention that, but I'm convinced a geartrain of it would work well, even as a plated coating on a standard gear.

Oh, and Paul- I was quite impressed with your handmade hobs- I just ordered a copy of Porter's "The Clock & Watch Makers Guide to Gear Making". Perhaps it will help me as well as it did you.

[Paul Loatman]

Paul, thank you for the direct comparison. I checked the data sheets- they are very, very similar. It must have been the so called "engravers brass" (353/56) that was indeed used mainly for clocks & watches over the ages.

If I want to be more traditional, I can, but to me, their metallurgical compositions are so close in Copper & Zinc ratios I feel either is appropriate.
My main concern now is sourcing large amounts- I have clocks I wish to build as well, and finding any source of 353 or 356 at a fair price in large size is a bit daunting. McMasterCarr carries 353 in a very narrow size range, and for brass, that particular type is absurdly expensive. It would be cheaper to smelt my own at home in a crucible, really- they want 1400$ or so for a 0.5" thick 24x48" piece- just one! That's flabbergasting. 360 can be found elsewhere fairly easy, and is far, far cheaper.

While brass can be sourced from many places, as well as gold, when we get into things like German silver, who retails that? I've never found anyone. I know various metallurgical makeups for the stuff, so I could technically make my own in a furnace of my design rather inexpensively, as I imagine the makers of Saxon did over wood fired furnaces and whatnot.

Any ideas if I went the route of German silver then?

As for Iridium, that's an even harder one to source, especially in the native iridium-osmium alloy that is found naturally occurring, which happens to have the best mechanical wear properties for gears, I feel. It must sound absurd to mention that, but I'm convinced a geartrain of it would work well, even as a plated coating on a standard gear.

Oh, and Paul- I was quite impressed with your handmade hobs- I just ordered a copy of Porter's "The Clock & Watch Makers Guide to Gear Making". Perhaps it will help me as well as it did you.

I have to agree about the 356/53 vs 360 they're very similar and i've worked with both and they are very similar when working. Both are easily machined and either one would be much better than one of those "red" brass alloys.

German silver is very easy to find, you can buy small quantities at decent prices, are you searching for "German Silver" or for "Nickel Silver"? You won't find much if you look for the former, but the latter will result in some good sources, it's also known as nickel copper and cupro nickel. However, like brass there are a lot of different nickel silver alloys out there, what i used in the past for non-horological things was 770 because it was the easiest to find, but i have no idea what would be best for watches, i found it to be difficult to machine. The only thing i've used in horology involving nickel silver was for my balance wheel which was 715 and it was quite difficult to machine as well, but it's physical properties are what sold me, although 715 might be more difficult to get than 770.

Porter's book will definitely come in handy, it's one of the best horological books i've ever read and is very straight forward, which i appreciate.

[David Walter]

The 35300 grade is what was and sometimes still is called "Engravers Brass", in Austria it was called "Uhrmacher Messing, or watchmakers brass ".
Formerly it was sold in 1/4 hard, half hard and full hard, for the most part today it is the half hard that is available. unless you request a a special order.
This brass is used as it is harder than the other alloys, has good properties for wear (most clocks do not have bushings or jewels so the plate becomes the bearings) and is very durable for wheels, for machining it is free cutting, does not tend weld to cutting tips or bind and produces a small, clean chip leaving a good surface finish on the material. As for polishing, both brass alloys mentioned will produce a mirror polish if prepared correctly although there may be a slight color difference that appeals to one person and not another.

For sources try McMurray Metals; http://mcmurraymetals.com/
Sequoia Brass; http://www.sequoia-brass-copper.com/
Industrial Metal Supply; http://industrialmetalsupply.com/produc ... /brass.htm
Alaskan Copper and Brass; http://www.alaskancopper.com/
or Metal Shorts 206 382 0305

Paul is correct German Silver is usually called Nickel Silver, I haven't looked very hard but Rio Grande; http://www.riogrande.com/default.aspx
Have some but I am not sure of the sizes available, nickel silver is usually used in the jewelery trade in place of silver as it is cheaper and often sold as "tarnish free silver"

The traditional brass was different in all places and mix standards were not even close to accurate and repeatable until the late 1800's and they have been much improved in consistency since then. The English brass of the 1700's was far better than the French brass of the same time as it had less flaws and was harder. However the French bronze was superb and far better than the English bronze. Any brass you smelt will have to be hammered or rolled, as it comes out of the furnace is generally not suitable for use. The rolling or hammering process work hardens the metal and fuses any small flaws.
A good example is say a 200mm bar of round brass, the outside will be harder than the center because the center was worked less than the outer portion, there is only a small difference but it is there. Smelting brass for working is different from smelting gold intended for jewelery.

David

[Paul Loatman]

Hello Ophiuchus,

I've so far made about 5 balance wheels out of the 715 nickel alloy that i think i mentioned in this thread. It's good, but it distorts easily, easier than stainless steel at least, which is what Roger Smith uses.

While i was looking around for something that wouldn't distort but still be easily machined i came across a ceramic composite that can be readily machined and doesn't need to be prepped or finished in any way like most ceramics.

It's called "Macor", i came across it when looking around for information on invar and when i found it i first thought of this thread, because i know you were interested in more modern metal alloys, but if you really want to be modern i think ceramics, silicones and complex forms of plastics would be the way to go.

Here's a link to where you can buy Macor; http://www.ceramicproductsinc.com/macor.html

I'm going to make a balance wheel with it and see how well it works, from what i've read about it, it should work very well, one problem i do see is the density of it, it's very low compared to iron, so i may have to add screw weights or something, but that actually shouldn't be a problem because it's easily tapped and threaded.

I'm in the middle of moving and right now i have absolutely nothing to do so i've also been reading up on silicone and how to make simple molds and casts, i'm not entirely sure how accurate a silicone mold would be, but if it's accurate enough i think i may be able to make a mold of a hairspring, then cast it with a different type of silicone in the right mixture to make it similar to a steel spring, i can't think of how i would make a mold of an overcoil but a flat spring would be possible. I could probably even have the collet and stud part of the silicone.

Anyways, i'm just throwing some ideas out and see if any good feedback comes from it, a forum like this is great as it can build a really good "collective mind".

[jadewatchmaker]

I'm new, so don't know if it is too late to reply on this. Though I am new to making watches I have been in repair for 25 years so have made a number. I have used mostly O1 steel for making parts but have also tried A2. Most parts do not need heat treating after making and A2 has better machinability and comes about the hardness you would temper O1 to so hardening is not an issue. I have also used Starrett feeler gauge material because it was cheap and came in many more thicknesses than their flat ground stock but found it way too hard. I was unable to temper it.
On the German silver I have heard that the version called Maillechort is the easiest to machine. Somewhere I have info on where to obtain it in Switzerland but could not find it today.
I have considered both gold, german silver and stones such as sapphire for plates. I was disappointed to see Audemars come out with a tourbillion in rutilated quartz plates as I had already thought of using it and even have a nice piece. I was very interested in reading the article on gold and finding out about a gold which will harden under temperature. Though I have been a jeweler, I did not know that one.
Yes, as you may guess for a watch case I have used nephrite jade for my first watch and intend for the second watch to use it also albeit a different color.
I'm enjoying this forum very much and will be hopefully posting some of my work soon, jadewatchmaker