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Someone had tried on a large Sector watch at the jeweler shop. Only later the owner found that the person managed (how?!?) to snap the stem in the little time he handled it, but didn't say anything. The crown is signed and of a peculiar look, of course Sector service center said that it's not available anymore. 
Then, somehow I botched on the correct way of removing a stem broken flush on the crown, that is to cut around the top of the female threaded section about 1mm to grab it. The sliding portion left for good and the fixed one was ruined. Time to think something different, all in all it took about two years until yesterday.

All work was done an a non-watchmakers baby lathe with standard tools. An extremely useful one is the carburetor jets gauges below.  These are now discontinued or sell for a stupid price but I had secured the pair from a German metrology seller. As the usual I apologize for the rough pictures.

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I started by drilling a blind hole in the original crown "core" to be the largest possible without touching the threads.

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Then cut off the button from a spare screwdown crown.

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That revealed the mistery of how the pipe, which holds the sliding portion and its spring, is attached to a screwdown crown. It's screwed in as well!

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But, once turned to press fit size into the hole of the original crown (3mm) there was not enough material to hold a firm friction fit. That I remedied turning and pressing in a brass sleeve. I left the contact surface a little rough to improve friction on the 0.05mm interference. I don't know why but most of my mechanical repairs involve sleeving and shimming.

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Then I turned a tube to push the above into the crown. It's sized so to be also used as a stump on the staking set.

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It went in without issue. Compressing air in there is not ideal, but once I realized it was too late to pull it out back and cut an escape groove.

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The finished item works fine on the case, all is left to do is to cut a new stem to size and return it to the happy jeweler.

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    • I believe @nickelsilver has a setup like that.
    • I posted pictures earlier in this thread. My lathe and mill are two separate instruments. I think I have seen examples of putting a milling head on a lathe bed...but not certain.
    • Timex Camper, September 1994, new to me. Strap is an old perlon with "Germany" in script etched into the resin on the tail end. Not Horlon or Eulit I believe. History unknown, running strong, losing less than a minute a day. Goals for this: Wear it a ton! Buy crystal lift, clean out the gunk around the ring and under the crystal Eventually swap into a stainless steel case. I've seen a member who has swapped a Timex mechanical movement into the Timex J.Crew quartz field watch case.
    • One of the problems we would have with a watchmaker's lathe is they were made over considerable span of time and manufacturing in the early days probably wasn't as good as it was today. Then if you look at the older catalogs typically it was just the head a few collets and something to rest graver on. So basically a basic lathe with over time things acquired but acquired things may or may not fit. Order today you purchase a used lathe that all kinds of nifty bits and pieces from a seller that acquired from? This would come back to that the basic watchmaker's lathe was used for basic watchmaking like turning things with a hand graver. Then limited indexing is fine because you can make things like stems Which don't need a whole bunch indexing   In the link above the word vector is mentioned and at the link below you can purchase one. Then of course you're going to need the motor that's a little bit extra for the price. https://www.hswalsh.com/product/lathe-vector-watchmakers-48-collets-hl11. That you're going to need some bonus parts like these found this picture online show the classic way of classic gear cutting.   The lathe could have a much bigger indexing disk but it has to be mounted close to the edge. Otherwise you're going to have a whole bunch of smaller disks like this which I think has notches rather than holes. Then as wonderful as these pictures look actually cutting a gear with this is not entirely fun. Look at all is belts all pulling on things and this is a watchmaker's lathe lightweight with lots of bits and pieces attached. It would make more sense if you actually cut a gear with something like this and it tends to be it's not really the best way to do it looks nice on paper but it is not the best way to go. Reality for cutting watch parts would be a bigger machine is much better. Than getting rid of all those belts and pulleys also good. Here is an interesting channel I would've liked of found a different video but this was nice and short if you look at his video as he uses a stepping motor and worm gear assembly for the indexing plate. In this particular video it gets attached to the lathe at about one minute and seven seconds and it looks like it's hiding looks like he has a Sherline. I do know he's had other stuff you'll just have to go through his videos to find it. Then at about one minute and 22 seconds you find out if you set up things appropriately. It's always bad we end up with half a tooth at the very end. Then you will note big lathe yes he's getting a big gear but you could easily cut a watch gear with the setup. And it definitely way more stable than a watchmaker's lathe.         Oh here's a company they been in business since 1911 http://www.fwderbyshireinc.com/  
    • Hello and welcome from Leeds, England. 
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