-
Recently Browsing
- No registered users viewing this page.
-
Topics
-
-
Posts
-
By nickelsilver · Posted
The tiniest screws are usually ones used to hold down cap jewels or Geneva stud holders in small high end calibers. 0.30mm threads are sometimes seen here. Smaller than that I've only seen on really small balance screws. I've made 0.25mm thread balance screws; that required making an adjustable die with a 0.30 tap. I asked my tap supplier if they had a 0.25 tap as they didn't list one, and they said yes, then called back to say they do but they are reserved for one specific customer. I think that customer must be Nivarox. Luckily 0.30 and 0.25 have the same thread pitch. Waltham made some amazing automatic cam operated lathes already back in the late 1800s, really the first of their type and the origin of the term "screw machine" which became what all cam operated lathes were called- up until the Swiss innovated with lathes where the workpiece itself moved, sliding in the headstock collet. These are called a- wait for it- Swiss Lathe. Die is 8mm diameter like the old standard dies (which are no longer made, at least good ones). -
The part you've linked above is the 242 canon pinion. the 227 3.55 high is on Cousins as you've shown but isn't listed when you do a parts search for the 2892.A2 If you're measuring 3.6 then I think this would be the correct one as your original post. -
It's this one, though weirdly the part code on the link ends 'h315' rather than the 'h355' it actually says on the site, tying in with the height of 3.55mm https://www.cousinsuk.com/product/eta-2892a2?code=ETA2892A2242H315# https://www.cousinsuk.com/product/eta-2892a2?code=ETA2892A2242H315# I note that dimension 'C' is given as pivot end to pivot end. -
By Neverenoughwatches · Posted
The rolex...the rivets made to brake away easily, probably what you saw happening with the Horia tool. It's not just about bending the balance wheel arms , which seems to be what these accessories prevent. Potential staff hole deformation....over one or many staff changes. Then we have Chronoglide popping out staffs with a staking set and proudly showing a wobbly wheel. ?? Removing the staff is just one part of the process of replacement. Staking on a new one is just as easy if not more so to mess up. -
I was in London recently and took the chance to visit the Clockmakers Museum which is now hosted at the Science Museum. It’s free and well worth a visit if you are in that neck of the woods. One of the exhibits was this screw made by Waltham. The blurb says you can fit 47,000 of them in a thimble 😵💫 I assume it was used in a watch and they didn’t just make it because they could. It made me wonder though, how on earth anyone could work on something that small. You can “see” it in the centre of the box in the picture; although you can’t really tell what it is. For all I know they cut a grain of sand in a half and put that in the box!
-
Recommended Posts