Bulova Accutron 218-N4

September 15, 2020
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Well this one was a big project but one that turned out beautiful in the end.

This was sent to be my a friend Peter Hurst who sent his Bulova 666 Snorkel in for a repair, It needed donor parts and luckily he had this one lying around so sent this with it. I repaired and serviced his Snorkel and he allowed me to keep what was left of the donor watch as I was of no use to him. I had taken out a coil and a few other parts that could be swapped. They were both 218’s but different variations so not everything is compatible.

Here is his Snorkel, a lovely looking watch.

I kept on looking at his donor and thinking that I needed to get that restored, it has a great dial and original bracelet, with quite a lot of work I could get this to as good as new.

Here is the watch as I was before I worked on it.

Definitely potential. So I stripped back all the movement and managed to source another donor with a working coil.

On rebuilding the watch I had no end of trouble with the setting lever and stem. It has such a weird setup to all the others I have worked on. The hacking complication is done by a copper strip that makes contact with one of the screws that hold down the coil with the capacitor and resistor on it. This screw is gold, same size as in any other 218 but gold. When the copper strip makes contact with the screw the watch will stop. Pull the crown and the setting lever shoulder pushes this copper strip on to the screw to break the circuit and stop the watch. seems logical enough but I do prefer the simpler and in my view safer method in the other movements which is a pin that moves the pawl jewel off the index wheel. In the N4 leaving the fingers on the index wheel could lead to damage if you accidently moved the index wheel whilst tinkering.

So my issue was that every time I built the watch I would build with the stem and crown in the movement so I could set the time to fit the hands so the day / date changes at 12. All before casing the movement. To case the movement you would loosen the screw to release the stem, then case and fit the stem again. Now I will note that the day date compilations are not all that easy to fit and quite fiddly with the day wheel having what I call the spring from hell to fit.

Above you can see this copper strip.

what would happen to me is when I would loosen the stem release screw this would make the setting lever (that its attached to) rise up, as the copper strip is under tension it would slip underneath the setting lever . Then the stem would not fit in and tighten or operate. The only way to reset this was to remove all the dial and day date complications, strip down the keyless and reset everything. The of course rebuild the lot and try again.

I think this happened 5 times before I finally realised what I was doing wrong. This probable is written in a manual somewhere but I don’t have it!

So the key thing to do is to only loosen and remove the stem when its not in hack / time setting mode. This way the copper strip is not making contact so under no tension to move back to its static position.

The even when fitting the stem in I would have to push it all the way in, then slightly back it out again to feel / here a tiny click. This would be the nipple on the setting lever falling into the groove on the stem . Once you hear that tighten the screw and your all done. Honestly this took me so many attempts to work out its why I write this blog in case anyone else falls into this deadly trap.

I also somehow either broke or it was already broken a lever on the quick change day lever, so this was totally inoperable until I found a donor part. fitting meant dealing with the spring of death again.

Here is the spring, (from another watch) it sits in a recess and loopes though two bends before resting on top of the wheel “click” I have tried to highlight its path.

Here is the broken lever and then the new and old replacement.

Anyway onwards and upwards.

I now started the casework. Here is the case before any work was done.

As you can see its rather beaten up.

I sorted the brushing on the top by using fine wet & dry paper on a steel block and moving the case back and forth and following the contours of the case. Once all the scratches are out I use 1500 grit paper and some Scotchbrite as the final pass. It takes a few attempts to get the lines parallel but once I was happy it was onto the sides of the case.

These were badly scratched. I used a rubberised abrasive wheel on my dremel to cut under the deepest before then hand sanding with wet & dry up through the grades. It is laborious work but worth the effort. Getting this part right now means that when you come to polish that bit is easier.

My problem here was that the rubber wheel was too aggressive. I have used this method many times before successfully but this time it put slight dip in the center of the sides. You have to look to see it and some of you may not but for me I can so its disappointing. I can still rectify this but its long work and I did not really have the time / commitment to do it.

So here it is after polishing.

Here you can see all three stages. Polishing comprises of four types of compound and four types of wheels.

Now onto the bracelet. Nice links but badly scratched up from years of wear.

In the second picture you can see how the links have stretch and opened. I was able to close these using some pliers. One side was worse that the other.

Also see this on the bracelet wear, You can tell if the owner is left or right handed by the wear on the sides. One is always worse than the other.

Its worse than it looks in this photo. I used again my dremel with a tiny P600 flap wheel to follow each segments contours to remove the scratches.
This takes a very long time and under magnification. Once its good enough I can then just finish with an ultra fine scotchbrite pad.

Lastly the clasp. These are always very tough stainless and highly scratched. I have had comments on my YouTube video on the restoration of these that you can do it just with Scotchbrite. This is incorrect. In theory as it is abrasive you could but you would be rubbing it for hours to get under the biggest scratches. The way I do it is to use a hard non woven unitised wheel mounted on a shank in the dremel. These are for surface finishing in industry and cut stainless well. It gets very hot and you have to keep it moving or you will get flat spots but it will remove material fast! have to be very careful around the embossed tuning fork logo.
After that you can apply the finish with a scotchbrite pad.

I took this one step further on this one, I decided to tape off the logo with capton heat tape , cut it out and then polish. I am not sure it was like this from factory but it looks cool.

I personally think that looks really good and worth all the effort put in.

So there it is, such a transformation.

So all that was left was to put it all together. I replaced the acrylic crystal with a new tension ring one. The joy of acrylic is they are just a few UK Pounds yet make such a transformation.

So here is the final result. a few little videos and then the photos
Another watch rescued from the scrap bin to give service and enjoyment for years to come.

Thank you for reading my blog.

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