Tmuir

Is the fact the middle dial is for Bombay time, telling us something? I think I'll pass but I am intrigued as to how you set the times for the different time zones as you would need to be able to adjust them independently so you can adjust for daylight savings when they start and end in each zone.

You could try the oldschool way of vibrating it ontop of a pocket watch. 18000 bph is 150 vibrations a minute, or 25 in 10 seconds. STart the hairspring vibrating just before the second hand on the watch reaches zero and count the vibrations until it reaches 10 second. If your count is less than 25 its too slow, so shorten the spring, above 25 its too fast so make it longer. If you don't think you can count that quick video record it on your phone, use slow motion if necescary and then count them in the play back. Read the second paragraph on this link https://books.google.com.au/books?id=gML7DAAAQBAJ&pg=PT49&lpg=PT49&dq=vibrating+hairspring+on+glass+pocket+watch'&source=bl&ots=X-TZ1ZJWQs&sig=ACfU3U20BIbXyE7zfl2nI7YPx06-xXOPTQ&hl=en&sa=X&ved=2ahUKEwiPs9XO6ornAhWqIbcAHY2_AGsQ6AEwEXoECAoQAQ#v=onepage&q=vibrating hairspring on glass pocket watch'&f=false

No offense really taken, most people call it a shed, I just like to call it a workshop to distinguish it from the 'shed' that stores our push bikes, brush cutter and chainsaw. Also if I call it a shed my wife thinks that means it can be used to store stuff rather than a place for me to fix and make things

I have a workshop, I get upset with my wife when she refers to it as a shed. But it is set up more for 'dirty work' has big my lathes, milling machine, cold cut band saw, buffing and grinding machines, ultrasonic cleaner etc in it, good for many things, but not for watch work and earlier in the evening it would of still been too hot in there as it was 37C today and my workshop is made of colourbond, has no insulation or cooling in it. The glass of malt whisky did the trick though. :-)

It's school holidays where I live and I have 2 sons, one 15 and the other 12 turning 13. The older one has 2 of his friends sleeping over tonight and my younger son has 1 friend sleeping over, so I currently have 3, 15 year olds and 2, 12 year olds high on sugar running around the house between the games room and their bedrooms. Not even going to attempt to do any work tonight, think I will just go get myself a nice malt whiskey and hide upstairs with headphones on. It's probably the safest thing I can do.

Looks like time for me to keep an eye out on ebay then. I'm still going to try and fix this though, if nothing for more than practice

On the weekend I went for a day trip to York which is a small country town about 80km away from where I live and after a nice lunch visited a few antique stores. I stumbled across a Jaeger car clock movement that I just couldn't say no to. On getting it home and opening it up I discovered it looks like someone at some point sprayed the platform with WD40 or CRC or something like that which of course dried up, attracted dust and then rust. I have stripped the platform completely apart and given it, its first clean and I'm pretty confident I can clean up pretty much everything except the hairspring which has rust spots on it, so will need a new hairspring. Just wondering how compatible the parts are between different ABEC or Smiths platform escapements as I'm hoping I can find one on ebay with a broken staff but with a good hairspring for a reasonable price. Here is a photo of the platform in all its dirt, rust and gummy oil glory before I stripped it down and cleaned it. The clock amazingly actually still ticked with the platform like this.

Found this post which gives me inspiration to be able to use a friction fit endstone. https://www.watchrepairtalk.com/topic/6024-replacing-jewel-in-a-rubbed-type-setting-using-my-lathe/

Its the bottom cap jewel that needs replacing. I've had a quick look at ofrei.com and unless I missed something it looks like they only sell friction fit jewels, I need the older rubbed in or burnished in cap jewel. I will have a look through your old posts though.

The Unicorn watch was made for Rolex. This is a big distinction, it was not made by Rolex, but was made for Rolex for Rolex to sell as the 'Unicorn' brand (They had other brands too Marconi and Wilsdorf and Davis was another). This was so Rolex could also have a share of the lower end of the market, but it backfired as people associated these cheaper watches too much with Rolex so the expensive real Rolexs sales dropped. In the late 1920s (I forget the exact year) Rolex dropped Unicorn and other brands to stop watering down the Rolex name. Bottom line due to the association to the Rolex brands these watches sell for far more than they should and being they were only ever made in low numbers nearly 100 years ago are pretty uncommon to find and when you can find them its not uncommon to see the sellers wanting $400 to $800 or even higher for these watches. So unless I get real lucky I'm unlikely to get another one for spares for a reasonable price. As a side note another company ending up buying the rights to the Unicorn brand and started making Unicorn watches again, all of these watches have Incabloc settings so are easy to spot and have a picture of a unicorn's head on the dial, they have nothing to do with this watch, but are regularly sold on ebay as 'Rolex watches' for stupid prices Here are a few 'genuine' ones on ebay https://www.ebay.co.uk/itm/vintage-Wilsdorf-and-Davis-UNICORN-ROLEX-SILVER-TRENCH-WATCH-C-1920s/233454163279?hash=item365af3d54f%3Ag%3AUC4AAOSw7c1diovu&LH_ItemCondition=3000 https://www.ebay.com.au/itm/Unicorn-Trench-Watch/163845237413?hash=item2625efeaa5%3Ag%3AbLsAAOSwPwhdbfBE&LH_ItemCondition=3000 and here are later Unicorns which has nothing to do with Rolex trying to live off the association. https://www.ebay.co.uk/itm/GENTS-1940-s-UNICORN-Hand-Wind-Movement-In-GWO-And-Condition/333331499064?hash=item4d9c1b0838%3Ag%3Af7kAAOSwk6Fdf3Qm&LH_ItemCondition=3000 https://www.ebay.com/itm/VINTAGE-UNICORN-ROLEX-AUTOMATIC-AMPHIBIAN-CALIBER-21-JEWELS-DIAL-1950/202792138232?hash=item2f375a75f8:g:g0UAAOSwoalc3wzZ

I've got a 1920s Unicorn watch which is my long term project as it has many issues, with the first one I want to fix being a cracked rubbed in cap jewel. I have a small selection of rubbed in train jewels and possibly a few balance jewels, but I have no rubbed in cap jewels. I could possibly replace the cap jewel with a friction jewel, but would prefer to keep it original, but haven't managed to come across any in the last few months of looking. If anyone is aware of any place selling second hand equipment that also has rubbed in end stones for sale please let me know. For those interested here is the watch. The other issues besides the cracked endstone is a broken balance staff and for me probably the biggest issue is the hairspring is snapped just a few mm from where it is pinned to the regulator, so I will need to find and regulate a new hairspring to the watch which is something I've never done before.

Archie Perkin's book Antique Watch Restoration Volume II has several pages going through the process to make a cylinder as described by Nicklesilver. If you do have a go at making one please take photos and post your progress.

A couple more photos. This first one shows the impulse mechanism. Every swing of the pendulumdrops the gathhering pallet on the end of the gathering wire (Its just above the tooth in what would be the 3 position on the dial) onto the saw shape teeth and rotates the wheel and the hand. When the hand reaches 30 it realeases the impulse leaver (for want of a better word) which drops under gravity causing the impulse wheel to run down the slope on the impulse pallet giving the pendulum a little kit. If enough people are interested I will upload to Youtube a slow motion video of this. The next photo is the master movement that sits on top of the vacuum tube under a glass dome that runs the master movement. It has been cleaned and serviced but cant be installed yet as the impulse carriage which I don't have a photo of has a broken pivot on a wheel and that part was off at another watchmakers being repivotted. (Its a joint effort between 2 watchmakers to restore all of the observatories clocks). The movement is sitting ontop of a basic wiring diagram for Shortt Clocks, which they hadn't been able to figure out why it did not match the clock they were working on, but my reference material solved that mystery as I managed to prove they were for clock number 94 (The other Shortt clock at the observatory) which is a Type B clock (simpler) than the Type A clock number 11 is.

I guess another way to put it would be : 'This is the most accurate clock any of us could ever hope to work on' As there are no mechanical clocks more accurate than this and you have to move to 'Atomic Clocks' to get more accurate and that requires a very different skill-set to work on. The Shortt clock is accurate to less than a second a year if run in a temperature controlled environment.

This was the clock that was used before the 'atomic clock'. The first atomic clock was built in 1949 but it was really only a proof of concept and didn't even reach quartz clock accuracy, the first accurate atomic clock was built in 1955 and the started to be sold in 1956, hence why the last Shortt clock was ordered in 1957 as after that date atmoic clocks were used. Shortt clocks were the most accurate clock available from the 1920s to the mid 1950s