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June 5, 2015 at 12:05 pm #49605
All:
I FINALLY got finished with this little monster. While the case hinge didn’t workout for me, I did get everything else repaired, so I thought I’d post the steps, the issues that I faced, and what I did to overcome them. Some of these I’ve posted before, but I thought it might be helpful to summarize it all in one thread.
Upon disassembly, I found that this watch appeared to have been “dipped” in some kind of lubricant to get it running long enough to sell it on eBay. This image shows the abundance of this mess in the movement.
After cleaning it and pegging the holes, I started to reassemble the movement and noticed that the detent screw for the winding mechanism was missing. I didn’t have one that would fit so I found a regular case screw that matched the threads, turned it down on my lathe, and replaced it. Because it didn’t need to be very tight, I was able to put a small screwdriver through the existing hole and tighten the screw that way. In other words, the detent replacement was seated on the watch main plate not extending up through the top plate as is typical.
All of the jewels looked good as did the bushings, so I turned to the mainspring. Since I couldn’t find a new/old stock replacement, I was forced to clean and re-use the old spring. I looked at the old barrel which appeared to be very rough. I put a felt disk in my Dremel tool, coated it with some Tripoli, and buffed it out.
After replacing the mainspring and re-assembling the movement, I found that the balance assembly amplitude was very poor. So, I removed the balance cock, turned it upside down, and noticed that the hairspring wasn’t centered on the jewel. After combing the hairspring I satisfied myself that the hairspring was now pretty well centered. However, when I put the balance assembly back into the watch and put a few winds on the movement, the amplitude was somewhat better but it still wasn’t as strong as it should have been.
Thus…… I pulled the balance cock out again, removed the hairspring, put the balance wheel/staff into my Jacot lathe, and burnished both pivots with a boxwood slip coated with wintergreen oil (I can’t tolerate the smell of turpentine). OK… so back in it went and the balance amplitude was now very strong.
Attempting to check the timing I decided to put a full wind on the watch. After about three turns the dreaded “snap” occurred. This sent me into a search for a replacement mainspring that I documented here:
<!– l –>viewtopic.php?f=5&t=1626<!– l –>The crystal was cracked so I took a measurement and ordered a replacement from a supplier who has a good supply of French crystals.
http://www.daveswatchparts.com/index.htmlI placed the bezel on my coffee pot warmer to heat and expand it, and dropped in the crystal which fitted nice and tight once the bezel cooled.
I did notice a hairline crack in the dial so I took this opportunity to use the technique posted by Dave on his sight. The process rendered the crack virtually invisibly. (Apparently, most of the hairlines cracks show up because microscopic dirt particles work their way into the cracks).
http://www.daveswatchparts.com/Info/CleaningEnamelDials.pdfHere’s the reassembled movement running strong.
Luckily I didn’t need to replace the balance staff on this watch as I would have been forced to have tried my hand at making one. I’m not quite there yet, but It won’t be long before I fall butt first into that as well.
I hope this helps someone… if by nothing other than learning to develop a bulldog tenacity and never give up.
Later,
TomJune 5, 2015 at 1:16 pm #62873Oh…
Here are some movement photos that I always take for documentation purposes.
continued…June 5, 2015 at 1:19 pm #62875continued…
June 5, 2015 at 1:41 pm #62874NICE WORK!!!
June 5, 2015 at 3:46 pm #62877Steve:
Thanks… It was a real learning experience to be sure. I might have spent $40.00 for this piece several years ago. Ultimately, it doesn’t matter as the case is silver and the movement is a practice piece. I have learned a lot working on eBay crap. If you can fix these things, then working on a really high quality watch should be easier. Since I don’t have any of those, I can’t really say for sure.
Later,
TomJune 6, 2015 at 5:26 am #62876Great job. Looks really nice.
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