Hi Guys

Thought I would share my adventure in bringing back to life a project watch. I wanted a 550 series movement and am currently favouring tool watches so, a Seamaster 120 seemed the way to go. Not too expensive or complicated. This is what I bought, surely paying over the odds for something not running, without movement pics and with an incorrect crown . The bezels are not available and this one looked not too bad. Hoping that it was mainly dirt and would clean off, I pulled the trigger on this 166.0027....


Pretty much as expected, looks terrible. I'm not sure if these should have a satin finish to the case but most I have seen don't. Would appreciate knowing. Bezel turns, no clicks (there's a reason for that, as I discovered later) but feels like it's running in treacle.

Some marks on the back but, it is already loose and comes off easily to reveal what looks like a very nice movement. The seal has turned to sludge and whoever previously removed the back managed to spread some on the rotor and the bridge near the balance. There is more sludge on the movement than oil! Not surprised it doesn't want to run. Seems to be from 1968 and as far as I can see is original.


De-cased and can finally see the dial. Yes, that is some black sludge on the movement holder, it seems to get everywhere. The dial and hands look really good to me, evenly aged and seem to be original but, I would appreciate any comments from the experts here.


I've cleaned and oiled half a dozen of these calibres now so stripping it is not too difficult. I'm just an amateur learning from books, experience and with advice from someone who knows so, after only a year, I am hardly expert in anything, except perhaps, knowing my limitations. Tightening a cannon pinion -yes, poising a balance -no (looks simple in theory ). I was quite adept at firing screws across the workbench but I seem to be losing that. Anyway, this is turning into a long story, so, apart from the black gunge, there were two problems. Not sure if it's clear below but the balance spring was stuck together in places.

Cleaned, demagnetized and it looks fine to me.


The other problem is a far bigger one for me. The incabloc on the bottom plate is not good as one side of the spring is not engaged and has little spring to engage it. This means the bearing is not properly supported. Fully expecting to break it, I try to adjust it to restore the shape. 30 seconds later and it's done - yes, it's broken. Now, I need to replace the spring and these are tiny and fragile. It also means setting the end float/shake of the balance as the incabloc frame needs to come out. The end shake is measured in a few hundredths of a mm, so many hours later (what is the correct way to assemble these blo**! springs in the frame!) involving 'Dial test indicators' and much coffee, I get this fixed and am happy that the end shake is the same as it was and compares to other movements I have. This is a (long and tedious) story in itself so I take a photo with the balance in the plate before it all goes back in the ultrasonic and I open a beer, or two, or four...

Next day, I build the keyless works and train. It fires to life and runs smoothly. There is something almost magical about this stage for me. Perhaps I'm just very affected... Well, I am an Aerospace Engineer and although I understand aerodynamics, I still look at big aircraft and say "How the hell did that get off the ground!". My wife says I must stop making such comments with friends who know what I do


More to come (assuming I have not bored you too much).
Chris.

 

Chris

Absolutely brilliant Great write-up, ace pictures, quite inspirational. Please continue this absorbing story to its (hopefully) triumphant conclusion . . .

 

Keep it coming, really enjoyable read!

 

Please tell me its done and we don't have to wait weeks to find out how it all turned out?

 

I don't know what it is with the bottom Incabloc spring on the 5xx movements but I have had more break than I have had stay intact. The revised spring is a bitch to get into the old block - I presume as a result of its re-design. My solution is to order a new complete block/jewel/spring (already assembled) at the same time as I order the mainspring. At worst, I have another block in the spares box. I measure the difference between the level of the plate and the raised part on the underside of the block before I press out the old one, then I press the new one in to the same height and it takes very little adjustment from there.

 

Great write up and the watch looks like it should clean up nicely too, the dial and hands look to be in very good shape.

 

great write up! wow, really inspires me to take it up!

 

A bit more, it's late in the evening here and I am spending some time with my wife... Anyway, Neil Young is looking after her Received a bezel removal tool and modified it for those with psioratic arthritis . Used an E-type lower radiator hose clip (XK-E for our friends across the pond).

Got the bezel and retainer spring off with some effort. Now, with the new crystal, seal, crown and stem from Cousins, I have this:


Bezel cleaned up pretty well. Still a half built movement but, I am further along than that now, calendar plate is finished:

Looks good, so added the dial and hands. I am very nervous with the hands as it is too easy to damage something you cannot replace. All well and now I can check the regulation.


All well and (Mothra) I am further on than this without any problems. I don't know, Stewart but perhaps I have been lucky as have not broken an incabloc spring before. I have a saying at work with my team "consistency is the key to success". I have no idea what it means but, the Spanish like it . Let's hope I don't keep breaking incablocs as I don't fancy spending hours fixing the problem each time.

More tomorrow.

Goodnight, Chris

 

Hi Chris

Yes, I'm pleased with the dial and hands. Never sure what you're buying with a picture through a scratched crystal!

Chris

 

Sublime! I want a 120 now

 

Chris, this is brilliant work… I'm enjoying every update…Keep em' coming!

 

Great project, love these SM 300-120-60, my 166.027 says hello:

Best Thomas

 

That looks a really nice watch, Thomas. A better bezel than mine, I am somewhat envious

Am going out for the day but another update of what I managed yesterday. On the calendar plate picture, you can see the lyre shaped spring on the incabloc. I like Stewart's idea of buying a complete unit as it did take me a long time to fit this... I fitted the plate on a steel block and measured the height of the frame on the plate with a DTI. Removed the frame, fitted the spring and pressed back in. First go got me to within 0.04 mm of where it started but, that is not good enough. Got it fairly quicky after that to the same position it started from. For those wondering what we are talking about, his is what the spring looks like (from the calendar photo).


Fitting the hands is only made tricky by the second hand shaft which is only supported by this V shaped piece. That meand you have to support this when pressing the second hand on. Anyway, I have a method now. This is from the rear side of the watch in the photo above. The watch is running so the third wheel is a blur.


So, after it ran for 42 hours or so, from full wind, which is better than spec and I mounted the hands, time to re-case the movement. First, press in the new Omega crystal and mount the movement on it's ring and it slips back in. Trimmed one or two mm from the new stem and fitted that as well. Here's how it looks.


I'm really pleased with this Some numpty has marked one lug with numbers which don't seem to be a service date so, will remain a mystery.

I haven't fitted the bezel yet but, can now see the watch from the front to compare to the very first photo.


Still left to do: fit bezel; rebuild the auto winder mechanism (on hold as I can't find the little tool I made to separate the reverser wheel); adjust as it is losing 5 to 10 seconds per day face up; fit strap and enjoy!

Cheers, Chris.

 

Chris

The movement looks beautiful, it's not often we get to see one without the rotor bridge. Losing 5 to 10 seconds at this stage is very good, ideally I like to set mine to gain just a little face-up and then they tend to lose just a fraction when they are worn so it balances out. It's going to be a very nice looking watch

 

Great work Chris.

 

Hi Stewart,

Can I ask what tool you are using to unclip the arms of the spring out of the setting, and to put them back? The springs should not be breaking. They will sometimes come out of the setting and have to be put back in, but unless they are already damaged, they should not break.

I have serviced hundreds of these and can only recall once having a broken spring....

Cheers, Al

 

Hi Chris,

Something I will recommend is that when you are supporting the pinion for the sweep seconds hand, and the friction spring is in place, that you protect the spring from being damaged by inserting a piece of old mainspring between the pinion and spring as shown here:



This prevents the flat portion of the spring that contacts the pinion from getting damaged and looking like this:





The spring is designed to provide just the right amount of friction, so enough to keep the seconds hand from looking jerky, but not so much as to reduce the balance amplitude significantly. Not sure if you have a timing machine or not to check the amplitude, but preventing the spring from being damaged like is shown above will help make adjusting the friction easier in my experience (aside from being good practice not to cause any damage while working on the watch).

Cheers, Al

 

It's similar to Rodico, but this is made by A*F and it's called "Rub Off"

http://www.esslinger.com/a-frub-off-1.aspx

Take the claims on that page with a big grain of salt by the way....

 

Hi Al,

Thanks for taking the time to explain that. It is better than my way of moving the spring to one side and supporting the pinion. I shall use it from now on. I did my first 565 as you surmised and afterwards realised what could be happening. Mine didn't look like your pictures, thankfully.

I have just ordered a cheap timing machine. One of the Timegraph 1000 models. I've resisted buying one before as there is so much to learn just picking up the basics. It just seemed a further complication and I didn't want to get distracted. I've been checking them with the simple method of monitoring over a 24/48 hour period for each position. This just tells me they are running in spec (except one which had/has an issue ) so, it will be interesting to see the amplitude as well. I suspect that interpreting the results will be difficult in it's own right....

As I say, thanks again for the tip. Have just got back from a day out so am off to fit my bezel!

Cheers, Chris.