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Welcome to the forum Kevin. Don't listen to Will and Bob, they have succumb to a horrifying horological mental illness: Will's condition is full blown chronic, and Bob is showing the first frightening stages of this symptom. We've tried medication, and even a forum intervention session: where we threatened to make them wear cheap Chinese watches with a complete plastic gear train ... but sadly without success :( All we ask is that you keep beautiful and exotic watches away from them until a cure is found ... and we thank-you for your understanding with this tragic situation. ;)

Patek pocket watch repair – Part 2, making and replacing the balance staff, new stem fabrication In Part 1 of this repair I had to make a new arbor for the escape wheel (see my earlier post if you haven't read it). Unfortunately the bottom balance staff pivot was bent and when I tried to straighten it out with my Seitz pivot straightner it snapped. Obviously it was much harder than normal as the pivot straightner should have been able to do it's job. So with no access to any spare staff, I had to make one. Here is the old staff being pressed out of the balance after I cut away the rivet. Someone had previously replaced the staff as there was a slight bit of material removed around the balance arm hole. With the staff removed I was able to take the dimensions and make a new one from round silver steel stock. Luckily the staff is quite large and measures just over 5.00mm long making it easy to work with. The pivots measure 0.10mm. The new staff was riveted to the balance and the roller table installed before it was poised. Poising is checking and adjusting the balance wheel to make sure that it doesn't have any heavy spot. In other words “balancing” the balance wheel so that all the mass is centered on the pivots. Poising is mandatory and always required after a new staff is installed. If the poise is off and the balance is heavier on one side the vertical rate will not be accurate. The original stem was in very poor condition and did not fit the hole in the mainplate, being somewhat too small which was causing all sorts of problems. Here's the new stem I made In this view you can see that the new stem fills completely the mainplate hole, no side play anymore

You'll be more than welcome!

I knew an old clock repairer more than 30 years ago who used to mix plaster of Paris with molten candle wax to repair enamel clock dials, when set it could be shaped & polished to match the original. Amazing stuff ! .

What a gorgeous movement, and in the safe hands of skilled man. Top write-up with lots of excellent pics too. Thanks for sharing it Geo

Hi John, I think you'll find it's a Longines 22AS http://www.ranfft.de/cgi-bin/bidfun-db.cgi?10&ranfft&&2uswk&Longines_22AS

OK you've had no takers on this one so here's one way to file a perfectly straight and square edge. First scribe a line that you want to to file down to. Next file down to about 1/32" above the line keeping the cuts as square as you possibly can. Now clamp a piece of square or rectangular metal bar perfectly in line with your scribe mark, leaving the 1/32" protruding. Finally file the remaining excess off while keeping your file pressed down flat on the bar of metal until all the excess is removed. You will now have a perfectly straight and square edge the you required. Oops, I forgot to say..............WELCOME TO THE FORUM! :)

Great video, can't wait to see the whole series. Soon the mods will have to stop recommending the TimeZone courses and just link people to a playlist of your best videos.

Thank you Geo and Bob. I am going to try a new generic hand and see how that goes......For some reason, a new sweep pinion costs over $40, and so a generic set of hands would be a better solution ($12.00) at this time. The strange thing is that the watch was working fine--and continues to keep time--up until the moment I noticed the sweep hand hand had become stuck on the minute hand, and later it came off completely. Perhaps at that moment the tube on the hand was damaged or stretched out. At this point, this is as likely an explanation as any. More to come.... JC

Thought I would give it a test run today. The height of the bench is perfect for me - no more bent back, this is really good. Unfortunately it feels very strange not working on a bergeon work mat, in fact it feels like i'm doing something naughty! New one on order :) Here's a couple more pics: I could prolly increase the light in the room by another 20% when I clean all the dust off the windows :D