Broken Carbide Bit

[Dave B]

SOme days it just doesn't pay to get up. Took a Cartier clock (really an 18s pocket watch in a little bedside case, labeled Cartier, wit a cloissenne bezel and dimond hands) in for repair. After struggling with the cross threaded case , I managed to coax it open, only to find the following problems: broken balance staff pivot, chipped top jewel in the balance bridge, tangled balance spring, completely smashed second wehhel upper and lower jewels, chipped third wheelupper jewel, wrung off crown wheel screw, and the barrel end broken off the mainspring. Of course thee is nothing whatsoever inside the watch to give a clue as to who made the movement, so I will have to measure all the jewels, or their respective pivots and order replacements for these by size. That is not an insurmountable problm. After fussing with it for about 1/2 hour, i managed to untangle the hairspring, and, surprisingly, see no kinks in it. SO then I tackled the sheared cap screw. Well - it was just far enough down in that I couldn't get a graver in ther to smooth off the sheared portion, but I did namage to get a reasonable dimple in the center of it with a small center/countersink cobination drill. SO I chuck up a 0.80 mm carbide drill, to drill out teh center of the screw. Of course, it walked off slightly, and before I could get my foot off the pedal, snaped off the carbide drill, in the hole. So now, I either need to get that beast out of there, or somehow come up with a new mainspring arbor. SInce I don' teven know who made the watch, other than it ifs fifteen jewel, and looks to be either French or Swiss, I'd really like to try to salvage the existing arbor. Does anyone have any suggestions for getting the mess out of the hole?

[Cary Hurt]

Dave,

I'd think it would be easier to source a replacement arbor. If you can provide the critical dimensions, I'll be happy to look at my spares for you.

You may be able to turn down a larger one to fit.

Regards,

Cary

[bkerr]

Do you know any one with an EDM? Carbide should be no problem for this process. The problem will be finding someone to do s goverment job at the machine shop.

[Dave B]

Thanks for the responses. I received a PM from someone who can do edm work down to 0.30 mm, and am going to get the broken piece cleaned out. So now all I have to do is start mearsuring and taking notes for pivot/jewel sizes, and dig through my stock of balance arbors to see what I have that is close enough to machine a new one from.

I swear - this watch/clock looks like someone threw it against a wall. Since it is a bedside clock, that conjures up images of a rather heated ...um...."discussion"....in someone's home!!!