hey, Woz is wearing a nixie watch on TV right now. yours?
Aside from the requisite advances in mechanical reliability, I wonder if the relatively sophisticated timekeeping demands of some of the WWI tactics(especially later war) helped out.
Something like a creeping barrage would be a friendly-fire meatgrinder unless everyone involved was keeping an eye on the time.
http://upload.wikimedia.org/wikipedia/commons/f/f3/First_Battle_of_Passchendaele_-barrage_map%28colour_balance%29.jpg
This is the brand I always associate with hospitals around here. Youāll probably have less trouble convincing men that itās ok to drink when your water is āclear as Prince Bismarckā.
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Try photoetching. Intricate patterns are possible to make that way. Railroad/ship/airplane modellers use this for ages, the technique is pretty similar to etching homemade circuitboards. There are tutorials online.
Do you know how well the photoetching process deals with āundercutā on thicker materials? With circuit boards, you have to be running very tight tolerances, or very sloppy etching, for that to be much of an issue; but PCB copper layers are thin. The protective grille/dome-thing on that watch looks like a slightly sturdier part.
Iād be delighted to hear that it would work, hence the inquiry, and Iāve never tested etching on thicker stock; but having seen it occur(with a magnifying glass) on my lousier PCBs, it struck me as a concern.
If that is indeed a problem, you could probably get away(with more elbow grease and a bit of craftsmanship) with dremel-bodging. Something like the 9910 or 9904 will more than adequately remove aluminum, brass, or steel that isnāt specially heroic; but the smooth portion of the shaft can be controlled with an (oval, in this case) template cut from acrylic, wood, even sturdy cardboard, and mounted on top of the metal. Maybe clean up with a 953 to hide any unpleasantries from view. It would make a jeweler cry, and a swiss watchmaker abandon neutrality and isolationism in order to punch you; but itād probably work. (General note about dremel bits: the official ones are a bit of a rip-off for routine work, especially those damned, brittle cut-off wheels; but even if you donāt buy from them, having a ācanonicalā model number makes what you want easier to hunt down. Also WEAR YOUR EYE PROTECTION; unless you are against having eyes or something.)
(Edit: the obviously correct approach would be die cutting, which could be achieved in one swift, precise, beautiful, operation; but youād need the appropriate die. Perfect if you plan on having one of these on the wrist of every conscript fighting to defend your glorious patch of razor-wire-strewn mud; but uneconomic for quantity 1ā¦ A pity. Sinker EDM would be suchā¦gloriousā¦overkill; but again, wholly impractical, alas.)
Yup. Heās a great salesman, and he works for free.
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Been there, done that, sometimes the circuitboard disagrees with the etchant and refuses to etch at one place and goes just well at another and then undercuts. I use laser-engraved spray paint as a resist (the photoresist way was a bit too finicky for my tastes, as was the toner transfer; with laser it is just brute force) and apparently there are sometimes little bits of residues. Or there are issues with board cleaning. The process is being investigated, each new board made provides more data points,
Generally, a fast etching bath will do less undercut. Not always but generally. I also had an anecdotal experience just two days ago with a very fast bath that etched a recalcitrant board (which was on a weaker bath for a half hour without much sign of progress) in about a minute, with no detectable underetch.
Undercutting is certainly a concern. You can however count with it, as it is a fairly deterministic process. This is a problem even in smaller dimensions, e.g. in semiconductor-grade lithography There is a method there, plasma etch with ions accelerated perpendicularly against the wafer, which does not undercut; but plasma-etching of 0.25mm brass sheet is a bit of an overkill. Not that I would mind having the necessary gear!
Sounds to me like a lot of work. But it is a work just perfect for a small CNC machine.
Also a good idea after the etch, as there will be sharp edges under the resist. (From every exposed point of metal, the etchant will eat in all directions. Overlay the wannabe-spheres, iterate, get the underetch pattern. Exception, grain-orientation specific etchants engineered to go strongly anisotropic. See also chemical polishing and certain metallography etchants.)
The swiss watchmaker bit is a piece of pure art! I may borrow that expression. 
I always go by eye and specs when matching the generic to the brand-name. But I should try to look at the model numbers, too.
Eye protection is a must. As a benefit, you can grind at odd angles, so you see the stuff well, even if it is peppering your face with tiny little grains of metal and abrasives.
The cutting wheels are ANNOYINGLY brittle! (The fiber-reinforced ones are thicker a little but much MUCH more durable.)
Not necessarily, perhapsā¦ It could expand your material choice with otherwise difficult-to-machine alloys. Graphite-coated sinker could be made one for all the holes, as they are identical, and just sink them one by one using a rotating jig.
You could also go for wire EDM, that can cut through amazingly thick blocks of amazingly hard metals, too. (And the EDM wire is some pretty springy brass thatās excellent for brushes and contacts and very fine probes for scopes and multimeters; touching contacts inside of a microUSB connector becomes easy.)
One day, there will be some homemade EDM rig out there. I saw something vaguely along those lines, made with an audiophile-grade 1-farad capacitor used for car stereos. Technically it is possible, and a sinker EDM is doable using the existing small-scale CNC machines; first pass to make the electrodes, second pass to sink them into the workpieces.
All these comments, and nobody is asking the real question, do you wear your watch with the face on the outside of your wrist, or the inside?
Outside for me, I just find it easier to read without twisting my wrist.
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I donāt think I ever saw a wristwatch worn on the inside.
What are the respective merits of either side?
Iād have thought inside is easier for drivers and outside for engineers, based on the angle of your arm and the likelihood of the face getting scratched, as well as the likelihood that your wrist has direct sunlight on it (inside would probably be more likely to provide shade).
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Heh, Iām thinking more like this -
http://www.chrono24.com/en/omega/speedmaster-professional-moonwatch--id2367710.htm
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I cannot hear the word āwristwatchā without thinking of the epic scene in the pilot of āMoonlightingā in which a rather unsavory man asks for one, politely yet persistently, while grilling sausages on an electric range as a casual demonstration of what he will do to the person who keeps it from him.
āThe WRISSSTwatchā¦ā he intones, over and over.
Aw. Bruce Willis is so young. And has so much hair.
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Hmm. I know a few people from local conventions who do their own circuitboard etchings. Iāll have to have a conversation with them, if not for a watch like this, then at least for some other project ideas. Thanks for the suggestion!
I forgot to include a video. Here is one.
(Edit: Etching starts at about 15:00.)
And definitely do it. Making stuff is fun 
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Iād at least seriously consider wearing one (I am definitely a nerd/geek) but the same things that make a conventional watch useful for me (working in places that ban smart phones and internet-synced computers) also rule out smart watches.
Anyway, the history of watches is interesting: I do not think of them as gendered artifacts. (Or rather, I donāt think of watches as inherently masculine or feminine, though it does seem that watches are the one socially acceptable piece of male jewelry, if socially acceptable is to include all living generations).
My girlfriend wears a Pebble. Sheās far sighted, so it just shows three big fat numbers. Try buying a watch like that. Her only complaint is that the tap to illuminate feature is a bit balky.
I have seen some nice looking mens Fossil watches that had big number digital readouts though that has been quite a few years ago.
Nurses wear them on the inside.
An aunt did it for that reason, and her mother. Who wasnāt a nurse. She did it for a different reason.
Both of which I forget.
No mention of the PacMan watch? I AM DISAPPOINT.
Stirling Moss, racing driver, wore a watch while racing, it faced out, Iām pretty sure they didnāt want any interferences on the inside of their space while steering or moving their hands in a confined space. Iāve seen nurses wearing wristwatches that actually go halfway, they face up when your arm is parallel with the body.
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