Week 6 Aug. 30-Sept. 4, 2010

Just going to be a short post this week. And I don't have any photos cause I keep forgetting the camera at school!

Anyways, like I said things didn't go very well on Monday and I had to do a lot of fixing to make things work. Had to remake some locating pins and such. then I went to make the recess for the stud holder and made the recess too wide so the whole bridge was useless. So after attempting to make the bridge 4 times I finally got it right...

Then I milled out the spot for the stud holder fixing screw and drilled and tapped the hole to 0.50mm. The bridge still has the full material underneath but I will be cutting that out way later.

Next I decided to drill the hole for the stud screw. Unfortunately I wasn't thinking straight (like usual) and drilled it in a random spot. This wasn't a good idea if I was going to use the original stud because it has a slotted side and that has to line up with the center of the bridge so the hairspring comes out perpendicular to the balance staff. So of course that didn't work out so I had to make a stud as well. This wasn't that difficult though even though it is one of the smallest parts in the watch. It is a pin that is 0.75mm in diameter and 1.80mm long. Then at the end there is a 0.25mm hole drilled through and also a small slotted edge for the screw to catch. And I had to make sure the slot was at the right degree so the spring comes out at 90 degrees to the balance staff. but after drilling a few holes off center I got it and it was fine.

Then I had to adjust the stud screw. This was really really difficult. The dimensions I was working with were extremely small. The screw is 0.40mm thread, and the head is about 0.60mm. The plan was to hide the screw in a recessed part of the stud holder. I went through about 6-7 screws before I got it to grab the stud and be hidden in the side of the bridge. It's really hard to explain on here how hard this was. If I have to do it again I won't be pleased...

And that's about it for last week. Next week will be lots of planning to get the right size for the balance staff and the regulating pins (nightmares to come soon)....

Cya