More Bulova Accutron 219 movement work

[ManSkirtBrew]

New forum member @ChrisMcKeith saw my previous thread about fixing the electronics in my 219 movement and was foolish trusting kind enough to send me his to work on. It's been an interesting journey and I thought some folks might find it useful or interesting.

The capacitor, resistor, and coils were all within spec, and a little pluck got the fork humming, so we were off to a good start. Full tear down, clean, oil, rebuild. Got to break out the Horia clone when the second wheel jewel surprisingly popped out of the main plate.

After depthing the wheel, I inly had to tear it down twice more because I forgot to put the hacking lever under the train wheel bridge...then forgot to put the fork under the train...good practice, I keep telling myself.

 

Then I started phasing it. Adjusted the tension on the index and pawl fingers by the manual, applied voltage from my power supply, and it ran...for a half revolution of the index wheel at a time, no matter how I adjusted it.

After some more diagnosis and manually moving the fork, I had the hunch that the index wheel has some bad teeth. 45x is as high as my microscope goes, but it sure looks like those teeth are rounded/flattened:

 

I compared it to the index wheel on the 219 I have that runs:

 

Seems like a big difference in the sharpness of those teeth.

Literally as I took this picture, I got a message from our friend @LittleWatchShop, who generously offered to try re-pivoting the 4th wheel on my 219. Since it didn't work, he's sending me a spare 219 movement!

Hopefully we can use the 4th wheel for my 219, and the index wheel for Chris'. The kindness and generosity here does not cease to amaze and delight.

 

[LittleWatchShop]

1 hour ago, ManSkirtBrew said:

New forum member @ChrisMcKeith saw my previous thread about fixing the electronics in my 219 movement and was foolish trusting kind enough to send me his to work on. It's been an interesting journey and I thought some folks might find it useful or interesting.

The capacitor, resistor, and coils were all within spec, and a little pluck got the fork humming, so we were off to a good start. Full tear down, clean, oil, rebuild. Got to break out the Horia clone when the second wheel jewel surprisingly popped out of the main plate.

After depthing the wheel, I inly had to tear it down twice more because I forgot to put the hacking lever under the train wheel bridge...then forgot to put the fork under the train...good practice, I keep telling myself.

 

Then I started phasing it. Adjusted the tension on the index and pawl fingers by the manual, applied voltage from my power supply, and it ran...for a half revolution of the index wheel at a time, no matter how I adjusted it.

After some more diagnosis and manually moving the fork, I had the hunch that the index wheel has some bad teeth. 45x is as high as my microscope goes, but it sure looks like those teeth are rounded/flattened:

 

I compared it to the index wheel on the 219 I have that runs:

 

Seems like a big difference in the sharpness of those teeth.

Literally as I took this picture, I got a message from our friend @LittleWatchShop, who generously offered to try re-pivoting the 4th wheel on my 219. Since it didn't work, he's sending me a spare 219 movement!

Hopefully we can use the 4th wheel for my 219, and the index wheel for Chris'. The kindness and generosity here does not cease to amaze and delight.

 

Yeah it was a disappointing fail. I turned a perfect center and was halfway through drilling ahen the bit broke. I was crestfallen. Live and learn. I am recovering well.

[JohnR725]

2 hours ago, ManSkirtBrew said:

I had the hunch that the index wheel has some bad teet

One of the tests or a test to tell if your index wheel has a problem is to do the following. So what you want to do is pluck the tuning fork so the index wheel was spinning and you watch where it stops. As you can't actually see where the wheel stops you look at how the arms are arranged. Then you do it again and each time you do it as long as a stops in a random position your okay but if it seems to favor a particular location or an exact location you have a bad index wheel.

 

 

 

[Alastair]

Unfortunately, 219 index wheels are difficult and hard to find. They aint the same as a 218 wheel. Took me a year or two to source last one, and that came from dead movement I got by sheer chance...

My advice would be to change the entire movement to a 218x Much easier than finding parts for the lesser common 219...

They are completely interchangeable as a movement (although some of their parts are not)--providing you choose the right type, ie, day date to day date...

 

[ManSkirtBrew]

Well, big thanks to @LittleWatchShop, as the donor movement was exactly what we needed.

I cleaned and replaced the index wheel, and the pawl wheel was definitely locking the wheel when I moved the fork manually, which it wasn't doing before.

Apply power and...nothing. No hum! Turns out the coil was bad. After testing and installing the coil from the donor movement, it started humming!

I adjusted the pawl and index fingers to get ready for phasing, and it instantly jumped to life.

 

[ManSkirtBrew]

One more update:

While I was getting ready to phase the watch, I noticed the finger jewels had skipped under the index wheel. Turns out there was an absurd amount of end shake.

After some quality time with the Horia clone (and a lot of practice aligning pivots in a bridge), I got the shake down to an acceptable level.

Phasing was actually super interesting. I used the method described here.

Started at 1.05v and turned the pawl adjusting screw until it ran smoothly. Jumped up to 1.75v, and the train started spinning noticeably faster. The method above says, "See if the index wheel is running normally or fast." I thought there was no way I'd be able to tell, but looking at the speed of the second wheel it is completely obvious.

I was able to get it to run smoothly up to 1.80v, and I called that good.

Re-cased, popped in a Renata 344, gave it a little tap, and off she went!