Forums
New posts
Search forums
What's new
New posts
New media
New media comments
Latest activity
Classifieds
Media
New media
New comments
Search media
Log in
Register
What's New?
Search
Search
Search titles only
By:
New posts
Search forums
Menu
Log in
Register
Navigation
Install the app
Install
More Options
Advertise with us
Contact Us
Close Menu
JavaScript is disabled. For a better experience, please enable JavaScript in your browser before proceeding.
You are using an out of date browser. It may not display this or other websites correctly.
You should upgrade or use an
alternative browser
.
Forums
The Water Cooler
General Discussion
Another OSA Owned Watch Rebuild – 1961 Bulova Type A17A Military Issue Navigation Watch
Search titles only
By:
Reply to Thread
This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Message
<blockquote data-quote="thor447" data-source="post: 3915183" data-attributes="member: 24867"><p>I had to wait for a few days to begin disassembly. This watch had a special type of 4th wheel that is pressed onto an extended arbor on top of the wheel train bridge. </p><p></p><p>[ATTACH=full]326500[/ATTACH]</p><p></p><p>In order to remove it safely without bending the wheel, it requires a special type of tool. It wasn't an overly expensive tool, and I've been meaning to get one for some time because I have a watch of my own that I've been wanting to restore that will require it, but I just hadn't bought it yet yet. This watch gave me the excuse to finally get one.</p><p></p><p>Once the tool came in disassembly began. Everything went pretty smoothly during tear down. No major surprises. There was a thin film of oil on nearly everything. The pic below shows a good example. The seconds hand is rotated around the shaft of a very small gear & pinion that is mounted directly in the center of the watch. This seconds pinion is driven off of the 4th wheel that required the special tool to remove, and the pivot on the end of the pinion is held upwards into the bearing by a very thin spring that puts slight upward pressure on it. This spring is mounted directly to the main plate and sits flat on the bridge until it bends upwards at that center pinion.</p><p></p><p>[ATTACH=full]326501[/ATTACH]</p><p></p><p>Once all of that was disassembled, you can see the oil from the underside of that spring as shown in the following photo:</p><p></p><p>[ATTACH=full]326499[/ATTACH]</p><p></p><p>A couple of other photos were taken, but I didn't go in depth with 'before' movement photos like the last rebuild I posted. All of the jewels had dirt and old lubricant on them as one would expect, etc. There were a few photos that I did remember to take though.</p><p></p><p>This photo is of the 'click', which is the part that engages with the ratchet wheel when the watch is wound, and makes the clicking sound you hear. This part allows the ratchet wheel to turn when the watch is being wound, but does not allow rotation in the other direction, thus requiring power to be released through the watch, and not by the barrel just unwinding. You can see old caked up lubricant on this part.</p><p></p><p>[ATTACH=full]326497[/ATTACH]</p><p></p><p>Another photo is of the top cap jewel of the balance assembly. This is under serious magnification, so I apologize for it's lack of clarity. You can see dirty and gunk on top of the jewel. Once disassembled, the underside of the jewel that actually interacts with the balance pivot wasn't much better.</p><p></p><p>[ATTACH=full]326498[/ATTACH]</p><p></p><p>Continued on next page.</p></blockquote><p></p>
[QUOTE="thor447, post: 3915183, member: 24867"] I had to wait for a few days to begin disassembly. This watch had a special type of 4th wheel that is pressed onto an extended arbor on top of the wheel train bridge. [ATTACH type="full"]326500[/ATTACH] In order to remove it safely without bending the wheel, it requires a special type of tool. It wasn't an overly expensive tool, and I've been meaning to get one for some time because I have a watch of my own that I've been wanting to restore that will require it, but I just hadn't bought it yet yet. This watch gave me the excuse to finally get one. Once the tool came in disassembly began. Everything went pretty smoothly during tear down. No major surprises. There was a thin film of oil on nearly everything. The pic below shows a good example. The seconds hand is rotated around the shaft of a very small gear & pinion that is mounted directly in the center of the watch. This seconds pinion is driven off of the 4th wheel that required the special tool to remove, and the pivot on the end of the pinion is held upwards into the bearing by a very thin spring that puts slight upward pressure on it. This spring is mounted directly to the main plate and sits flat on the bridge until it bends upwards at that center pinion. [ATTACH type="full"]326501[/ATTACH] Once all of that was disassembled, you can see the oil from the underside of that spring as shown in the following photo: [ATTACH type="full"]326499[/ATTACH] A couple of other photos were taken, but I didn't go in depth with 'before' movement photos like the last rebuild I posted. All of the jewels had dirt and old lubricant on them as one would expect, etc. There were a few photos that I did remember to take though. This photo is of the 'click', which is the part that engages with the ratchet wheel when the watch is wound, and makes the clicking sound you hear. This part allows the ratchet wheel to turn when the watch is being wound, but does not allow rotation in the other direction, thus requiring power to be released through the watch, and not by the barrel just unwinding. You can see old caked up lubricant on this part. [ATTACH type="full"]326497[/ATTACH] Another photo is of the top cap jewel of the balance assembly. This is under serious magnification, so I apologize for it's lack of clarity. You can see dirty and gunk on top of the jewel. Once disassembled, the underside of the jewel that actually interacts with the balance pivot wasn't much better. [ATTACH type="full"]326498[/ATTACH] Continued on next page. [/QUOTE]
Insert Quotes…
Verification
Post Reply
Forums
The Water Cooler
General Discussion
Another OSA Owned Watch Rebuild – 1961 Bulova Type A17A Military Issue Navigation Watch
Search titles only
By:
Top
Bottom