(Just for you, Jim) Here's another escapement, the Graham dead beat. It's drawn in a similar way to the recoil but is a better design. Anyway, the drawing takes a fair bit longer and you're encouraged to add in more detail than above so the escape wheel gets spokes and so on. This is all happening pretty fast in a clock so this is a good way of understanding how the locking, impulse and escaping work. I notice in the description on the video that I put "exit pallet escaped" when I intended to say unlocked. It only escapes at the very end, obviously. It's defined as 30 teeth on the escape wheel so each cycle moves the wheel 12 degrees. The impulse, or escaping, angle of the pallets is 3 degrees and the lock is 1 degree so the pallet swings 3 degrees in each direction and the wheel is locked for the first degree of that. Next up is the club toothed lever escapement so, into watch territory. Am working on a very beaten up ETA 2451 watch at the moment as well so might post some pics of that. I've also started getting into the notes and my course starts soon so, plenty going on. Just received a book about George Daniels CBE and realised he was also very much into his cars so, some good inspiration! Cheers, Chris
I watched the documentary, he said that he only collected vintage racing cars and he raced all of them. Very cool.
I've also got "The Watchmaker's Apprentice" but haven't seen it yet. Should be good now I've seen the sort of cars he owned. Like I said above, I have an ETA based watch open at the moment which I believe is late sixties. The case is GP on brass and is in a terrible mess. I think the only way to get the remaining GP off is by hand and I'm going to leave it as a brass finish. Clearly, a Bentima Star and on opening it, I found an ETA 2451. Nothing special but I'm beginning to appreciate ETA calibres as they have a good reputation. Signed rotor, which I think is a service ETA still offer today. One of the aspects of this work I like is the countless ways that the designers used to achieve the same aim. Here's a picture with the auto bridge removed. What's unusual here for me is that the click is acting directly on the crown wheel. When you turn the crown in wind mode, that wheel rotates and turns the ratchet wheel - all as typically done. The ratchet wheel is connected to the barrel arbor and winds the mainspring so, typically the click acts on the ratchet wheel to stop the mainspring unwinding it again when you release the crown. With the click removed, the crown wheel is free to slide away from the ratchet wheel which seems a bit odd. It's held against the ratchet wheel by the click and it's spring. You can see in the next photo that the wheels are no longer meshed. So, the crown wheel is sprung like this to work in the following way: Winding by the crown: the crown wheel turns, is meshed with and rotates, the ratchet wheel to wind the mainspring. Nothing can unwind as the click stops that happening. Winding by the auto rotor: the auto mechanism drives directly onto the ratchet wheel (you can see a small pivot hole just off the ratchet wheel two photos above at about 9 O'clock and the auto mechanism wheel is pivoted there). As it winds, it's turning the ratchet wheel which is trying to turn the crown wheel which can't rotate because of the click so, as one mating tooth climbs up the other, it pushes the crown wheel away until it "jumps" one of the mating teeth and the click spring pushes the crown wheel back against the ratchet. The ratchet wheel has now turned winding the mainspring. Not too many parts. The auto bridge holds the reversing wheels and it's other two reducing gears without separate screws. A small issue with the mainspring as it's in two parts... After cleaning and assembly started with the train just laid in place. As usual, the barrel drives the second wheel, which drives the third, which drives the fourth (and this will take the seconds hand as it's rotating once per minute), which drives the escape wheel and then the fork. Balance not shown which controls the fork movement. Dial side and keyless works (second wheel not shown): Train fitted and running. Rotor and auto bridge fitted and looking a lot nicer. Dial and hands fitted. Right, now for the case.... Can't see that being a quick job. Cheers, Chris
Hi Chris, You will see the DNA of modern ETA movements here like the 2824-2, 2836-2 and some others. I guess I see so much designed like this with the click acting on the crown wheel that I don't think of it as being unusual, but I guess it is in many ways quite different from the traditional designs you typically see from other brands. In layout of the train this movement is the same as the 2824-2, and you even see an earlier version of the 2 piece cannon pinion here. Just a note that the terminology you used as it brings up a point to be aware of. While the terms you used are correct for most watches, is a bit different for these ETA movements. What you are calling the second wheel is called the intermediate wheel in ETA terms, the what you are calling the fourth wheel is known in ETA terms as the second wheel, or sometimes called the sweep seconds wheel. If you need parts, you just need to make sure you use the right terms for that brand, and not just what the traditional watchmaking terms would be. Note that many of these ETA terms for specific parts carry over to modern Omega movements as well, particularly those that are based on ETA movements like the 2892 based movements. As you work on more and more movements you will find some unusual designs, and you may often be wondering what the designers were thinking when they did certain things. In particular some of the calendar functions I see on older movements seem needlessly complex for what they are doing... All good stuff though, and that movement cleaned up well! Cheers, Al
Thanks Al, I’m sure this is the first one like this that I’ve seen and had no idea it was used so widely. The only auto ETAs I’ve done are the 2892 and it’s Omega equivalent, the 1120. Now, I remember ordering parts for the 1120 and coming across this unusual nomenclature but had not realised it was used in general by ETA – something to be careful of, as you say. There are similarities here with the 2892 and it’s quite a nice little design. So, moving on to the case… What an awful mess this was with some gold plate left and a great deal of pitting. Now, I know we don’t polish cases on here but there is no option for this one as I’d say it’s really beyond any economic repair. I could clean it all off and try to re-profile it and then get it plated again but here, all I wanted to do was bring this watch back to life for a friend. It’s a brass case and the good part about working with brass is that it’s soft but that’s also the bad part. So, easy to re-profile but difficult to get any sort of finish other than polished so I ended up going for a polished look. It will tarnish but I’ll have some access to it later so can keep it looking nice. Worked with blocks and a couple of grades of wet and dry in an attempt to maintain some edges and then final polished. I wouldn’t be doing this on a good watch but, I’m happy enough with the result. Will put “case refinishing” on the very long list of things to look at, probably next year. Here on the wrist with a new crystal and the movement re-installed and looking far better than the starting point a few posts above. Nothing special but nice to bring it back to life and a new calibre for me. Cheers, Chris
Thanks! I did a little of my lever escapement drawing as well today and am quite pleased that it makes sense to me. All the labeled points are there for the construction but I've only drawn the wheel so far. This is also very interesting and quite involved. Will check this and then draw the fork and so on. I wanted to get to this as it's what I want to work on unlike the clock escapements above. Step by step though. Cheers, Chris
I've not posted anything about this for a week or so as I've been on the first course at the BHI. This was the Basic Mechanical Watch course about halfway down this page. I would recommend this to anyone who has an interest in the way their watch works as well as any budding Tinkerers and Watchmakers. You don't need any experience to do it and can go in without any knowledge. There are six on a course with one instructor, John, who guides you through everything. We had mixed group of ages, spanning 25 years (me at the top), and experiences with some never having opened a case before. I think you'd get a lot more out of it if you've done some pre-reading and have spent some time tinkering but it's not essential. Most of us stayed at the BHI where breakfast and lunch were supplied in their on site cafe and everyone said the quality was excellent. In the evenings, students and instructor trooped down to the local pub where again, the food and beer were very good. Have put on a few pounds.... You do end up being immersed in watch talk a lot of the time but you also chat about most things under the sun so, definitely worth doing that. Basically, you start with a cased pocket watch with an ETA 6497 calibre. These are big calibres and are still used by companies today, for example Panerai as well as Al at Archer Watches. So, a pretty robust movement with, in it's better forms, some great available performance. Being a pocket watch, the seconds sub dial is opposite the crown and there's also a 6498 with the sub dial at 6 O'clock when used in a wrist watch. Here's a quick picture of my 6498. This is big, far larger than a typical wrist watch and I think minimum case diameter is 42 mm with these calibres. It means that the screws are huge so less time spent crawling around on the floor.... No complications at all so, it really is the most basic calibre you can buy but contains the same basic layout as in, say a 565 or 861 just without any complications. Al and others always recommend getting the base movement working correctly and then adding all the extra parts so, this calibre has the same layout as many others, for example the train is barrel/second wheel/third wheel/fourth wheel/escape wheel/pallet fork/balance. This is the same as the base movement of a 565 but of course, the parts are calibre specific. As Al noted above some people rename the wheels and they can work in a slightly different fashion but if you can build this 6497, you can have confidence in building the basic part of a 565. I'll have to do this post in stages... Cheers, Chris
In a general way, this is how the course goes: First day after introductions, is spent reviewing basic tools, opening the case, removing hands/dial and stripping the movement. I thought John's explanations of what each part is doing and how to remove each item were very clear. They have a microscope connected to a large screen that he uses to explain as well as a white board for giving details and he made sure that everyone grasped each aspect. Second and third days are spent cleaning, pegging, adjusting end shake and so on with most of the reassembly. The discussions covered a lot of ground from different types of cleaning to train counts, end shake, side shake and oiling. Some of the guys had a fair amount of fun with the mainspring winders but he runs through the usage of staking and jewelling tools (of course, he'd messed up some endshakes late one evening...) as well as static balance poising. There was a long and very interesting diversion into balance springs and balance staff replacement but no practise from a practical point of view. That whole subject could take weeks if you're making your own balance spring and fitting it to studs and collet so, very interesting but I suspect not often used these days. At the end of Wednesday, the movement is built except for the escapement. Thursday was a lot of escapement discussions and adjustments. There's a lot in this such as lock, draw, run to banking, shock protection, regulator pin adjustment, guard pin adjustment, isochronism and the etachron system. Some of the movements had etachron and I'm a fan of this to adjust the hairspring and regulator pins. I really found this whole topic interesting and I think the way it was explained with large models and animations made it clear. It's at this stage where, I suspect, some people decide it's not for them as it's getting much more complex. At the end of the day, the movement is built and you've run the 0H tests on the timing machine and made any preliminary adjustments. Friday is running the 24H tests (really 12H tests as time is short) and a discussion of dynamic poising plus fitting hands, dial and re-casing. Quick visit to the museum which is virtually all clocks and it's over when you get the course notes and certificate of attendance. So, overall, he covers a lot of ground. All of the basics are there and covered in detail with the practical experience of working and adjusting your own movement. Excellent feedback from the instructor so you can see how your work is going. He's not just aiming to get you through the course but also wants you to work to the right standard even if this is a basic course. I really appreciated some of the parts that probably have no right to be on a first course, such as balance staff replacement, even if they were just explained. You also get to see various tools which otherwise can be a bit daunting. Most of the guys were into newer watches but I picked up some good tips on hand tightening/straightening as well as other tips that relate more to the vintage watches that are of most interest to me. We even had a discussion about 550 series reversing wheels so, he's happy to have a chat about specifics. If anyone is thinking of doing this course, I'd certainly recommend it. Worst part was probably this tower clock they had temporarily fitted in a storage area close to the workshops. It was so far out of beat it really started getting to me.....Note the placement of the PC box and the adjustment to the floor under the pendulum Cheers, Chris
I know you're joking but, I wonder what this really will mean. Decision made now and we'll see what happens in UK. I can't see exactly what opportunities will arise but with any change, there are bound to be some just as some people are bound to lose out. There's been a drop in the pound versus the euro and the Swiss Franc of 20% since last year so, anything from Switzerland will get more expensive. Against that, I suppose the Swiss will see UK labour rates as being cheaper and they are desperate for Watchmakers so, perhaps they'll set up more service centres in UK to cover Europe? From a personal point of view, being a Brit living in Spain, as long as I keep contributing here I can't see the Spanish government sending me away and losing my tax income and contribution to the local economy. Anyway, we still don't have a majority government here (second vote this year just finished) so we have our own troubles.... Cheers, Chris
Just to follow up what Al said about how ETA names some parts. In French (thus in French speaking Suiss), you usually call the 4th wheel the second wheel, the 3rd wheel the intermediate wheel, the 2nd wheel the central wheel (well, at least when it is in the center of the movement!). For instance, see the very good courses and explanations at horlogerie-suisse.com. I do not know why and since when French and English ways to call these parts are different. Not a big difference actually, but as Al said good to know when you are ordering parts, and when you read watchmaking stuffs in both languages.
Actually, although I make out that ETA seem to move in their own mysterious way with part naming, it is logical for the 2451 above. For me in a "classical" calibre, the train goes barrel, 2nd wheel, 3rd wheel, 4th wheel, escape wheel. As the 2nd wheel is usually in the centre of the movement, it is often called the centre wheel. The 2nd (centre) wheel turns once per hour and has the cannnon pinion (and to that, the minute hand) attached on the dial side of the plate. The 4th wheel turns once per minute so, if extended through the plate, a subsiduary seconds hand can be directly mounted to it. For me, the 4th wheel translation to French is not "second" as in 2nd wheel but, "Second" wheel - what I'm trying to say is that it's not the number 2 wheel in the train, it's the wheel that counts seconds. Underneath here is an Omega 565 extract and it's part 1243. The English is clear and the translation of the Spanish is "Seconds wheel" which makes sense with what I said. French is, obviously, not my first language but, that's how I read it and I'd be interested if you are thinking the same. Note that, for me, the French translation of part 1240, 3rd wheel, is "average wheel" and the Spanish is "first wheel". Seems like everyone likes to rename into something of their own choosing! Hard for me as a Brit, living and buying parts in Spain, as well as UK and France... Back to the ETA 2451 above.... What I labelled the "fourth wheel" as in 4th in the train is actually part 227 and for me is the "wheel that sweeps the seconds" and not 2nd wheel. The English description shows that as well. But this a an old calibre so, when I look at the parts for an ETA 2892-2 which is much more modern, for the same part, the name has changed to "Second (2nd) wheel" in English but the French name is still consistent. I am firmly blaming the French speaking Swiss for generating this confusion Yes, you need to be careful when ordering parts but, for most calibres a parts list with pictures and descriptions is available. Cheers, Chris
My mistake, it should be "Seconds wheel" (roue des secondes) in French (the English 4th wheel). In French : Barillet (barel) Roue de centre (2nd wheel) Roue de moyenne (3rd wheel) Roue des secondes (4th wheel) Roue d'échappement or roue d'ancre (escape wheel)
Hello Archer, Could you please elaborate on that please? I have read a lot of your posts concerning acuracy, adjusting processes and regulation, and I would like to thank you for your always interesting answers! It is a great pleasure for me to read your posts. As I am currently trying to improve concerning poising a balance and adjusting a watch, I would like to learn more about dynamic poising. I have read some stuff about that but must confess I am not sure to fully understand the theory. I have done some static poising - with good but not perfect results - but never dynamic one - I have to know more about that before trying! Thanks! François
I'm not sure of your skill level, so I'm not sure I can teach you this over the internet - this is something best learned from someone directly. But the theory of it is pretty simple - you want the acceleration of the balance to be zero when it travels through the lift angle. A heavy spot on the balance can cause the balance to accelerate positively or negatively depending on where that heavy spot is in relation to the pallet fork, so the vertical orientation of the watch (crown up, crown down, crown left, or crown right) can change what is happening to the balance as it moves through the lift angle. It might speeding up in one position, and in another it might be slowing down. These differences cause positional variation, so the dynamic poising process is a way of identifying that heavy spot and eliminating it. It is usually done on a balance that has already been statically poised, and note that it includes compensating for the collet and balance spring, which static poising does not. This means if you take a perfectly poised balance that you have done on your poising tool, mount the balance spring, then dynamically poise it, if you removed the balance again and checked the static poise it will not be poised any longer. The process is not particularly difficult to learn, but the part that most struggle with is having everything else on the watch absolutely perfect before starting the dynamic poising process. This is not a short cut to good timing, and treating as such will cause you nothing but grief. Of course you need to be able to recognize a poise error to begin with, and this is why it is the last thing done when I'm adjusting a watch. Only done after making sure the balance spring is perfectly concentric, flat, if it has a regulator that the terminal curve of the spring is centered in the pins, and that the pins are spaced evenly, etc.. Cheers, Al
I've been pretty busy so have let this thread go dormant for a while. I'm still moving forward with the course but, it's difficult to write much when you're at the bench and working on different calibers building experience. Anyway, will start posting more in a month or so. On the dynamic poising front, Al also gave me the same advice about this being a last resort and I've tried this once on a 565. Now, this may not be the best caliber to start with as any changes are not reversible but, I had a movement running well and had done everything I could with the spring, pins etc as Al advises. So, it seemed like a candidate to try dynamic poising and I had some spare balances in my spares box in case it all got out of control..... After doing my best with all other adjustments, it was running at 18 second delta over all positions at 0H and 24 seconds delta at 160 degrees amplitude. This is already well within Omega spec which specifies 25 seconds at 0H over 3 positions. There is a 24H spec which is 35 seconds and is probably the closest to a spec for 160 degrees amplitude. I don't believe that exists. Working through the 8 vertical positions, I decided on the point to lighten and with a slight twirl of a drill in a pin vice, removed some material - really, the slightest amount. That brought the deltas to 15 second over all positions at 0H and 17 seconds at 160 degrees amplitude. So, the effect was small. I'm sure Al could have got this closer but this was enough for me as the logic is clear. Like I say, this is well in spec anyway so I didn't see the point in going further. I'd take Al's advice and only do this as a last resort but have a read around it as it is interesting. Cheers, Chris
Thanks a lot! Chris, thank you too! I really appreciate your answers. Al, what you said seems pretty clear to me. But, if you do not mind, I still have a few questions. They are not necessary related to what you said, but to what I have read elsewhere, so maybe they are not relevant. 1) My first question could be for Chris as well. How do you exactly set the heavy point thanks to the different positions rates? What I have read concerning that point has not fully clarified my troubles. 2) I have read that the sort of heavy point the dynamic poising creates - or to put it in another way, the fact it modifies a perfectly staticly poised balance - could produce troubles if the amplitude changes. This statement - made by a watchmaker on another forum - seems to suppose that dynamic poising has some "side effects". It would be why Rolex did no longer pratice it after trying it for a while. Is that true? Why is that? 3) I have read that the effect of a heavy point, whatever caused it, could not be seen on a timegrapher at an amplitude of 220. Is that true? Why is that? (Concerning my skills: I think I am a good amateur, which means I usually succeed to correct my mistakes! Seriously, I have serviced lots of watches, including automatic ones, a JLC powermatic (cal 481), chronographs like Landeron or Venus 170. I have sometimes very good results - for example with a Lip R 25 of 50 years, with a delta of 8 over 6 positions. But it is not thanks to me: I only did a regular service with minimum ajustements... I feel confident with correcting hairsprings because I got some good results - very rewarding in those cases! But I have also killed several hairsprings! And I have not ever changed a balance staff or used a lathe. Long story short: I can service a good movement and fix some issues, but I am only an improving amateur. By the way, a time I had my watchmaking ego "regulated" downwards was when I got my first timegrapher... Here is the begining of the problems! You thought you had well serviced a movement and you see you have a 40 sec delta over 6 positions... But I would never regret that, because it is also the begining of the real stuff.) François
Hi Francois This is an interesting topic and I feel it’s worth going back a stage or two to see where you are first. So, it sounds as if you are at the stage I was a year or so ago and can service a movement to a degree and obtain reasonable results. Your comment about being able to obtain good results with minimum adjustments being down to the existing state of the movement is one I’ve made myself in the past. So, I think you’re a bumper guy but talking in general and I’ll try and introduce specifics for a 565 and a 354 as I go. Like Al says and bear in mind that a lot of my procedures have come from him, the first is to get the movement running in spec without doing any of these more difficult adjustments. So, when building the movement, here’s a list of some aspects that you need to consider (it’s not comprehensive at all): After stripping/pegging/cleaning: I review all pivots and jewels/bushes in a 40x microscope – if these are not good, then you’re always going to struggle. Also look at the wheel teeth and pinion leaves. I then oil and mount the shock protection jewels with the balance/cock mounted on the plate by itself. At this stage (good tip, Al), you have the best access to the spring and forgetting overcoil springs, can check it is flat and concentric. Once you’re happy with that, check the regulator pin gap and set it to about 2 or 3 times the spring thickness and then get the spring central in that gap. Don’t adjust the pin at the tip but at its root so that it remains parallel to the boot – if not, your dial up/dial down rates will vary because the spring does not have a constant gap depending on the movement orientation. I would recommend trying a modern ETA 6497 with the Etachron system as it becomes very clear how one adjustment affects the spring concentricity and centering in the pins and how little real adjustment is needed. Just a note on the balance spring is that you should only really be touching the part close to the collet or the part close to the stud – if you’re reforming dog legs then you’re into significant work. By the way, with the balance mounted like this, you can look at the ruby and see if it is aligned well with the fork/balance axis – this gives you some idea of which way to turn the collet later for fixed stud designs like a 354 when the beat error is out of spec. I check side and end shakes in all the parts as I mount them including arbor in the barrel, arbor in the plates and then all other items in the plates/bridges. Adjust end shake as necessary and if side shake is too great then essentially you are into replacing items. Finish assembling the movement checking oiling under the microscope as well. Be careful spinning the movement rapidly after oiling as some of these wheels are close to jewels and can suck the oil out all over the teeth. At this point, you need to check the escapement and there’s a lot here such as lock, run to banking, guard pin clearance and so on. I let the movement run for a few days after oiling the pallet stones and then consider it has settled down. The temptation is always to fix things immediately but, I think it’s better to let it run for a while first. So, now, I make the timing checks in six positions at both 0H and 24H and write them down in a table. Also, look at the timegrapher screen and see if you have any strange oscillations (could be wheels are out of true) or spurious points (could be balance spring is scratching on one pin). There are a lot of faults this will show you but, generally, you’ve already picked those up and corrected them. Below is a picture of one of my movement timing to show the sort of data – the overall rate is a little slow and the amplitude is a little low but there is a reason for that and anyway, I’m trying to show you the data you should be looking at. Really, for a non chronometer, you only need to check 3 positions and these are (assuming the watch is worn on the left hand on the outside): 9H Standing with hand in trouser pocket 6H Driving with hands in the typical position Dial up Hand resting on the desk Chronometer adds: 3H Watch on right hand, standing with hand in trouser pocket FH Dial down – hand resting on the desk with watch worn on the inside of the hand And then, Watchmakers may add: 12H This is not a normal position in use but is the last of the typical verticals “Dynamic poising Watchmakers” will also add: 1.5H, 4.5H, 7.5H, 10.5H These are the extra verticals used for the dynamic poising You can usually get a spec for minimum amplitude (must set the lift angle correctly), beat error and deltas at 0H and 24H as well as an average rate over 0H and 24H. Just taking the deltas – for a 565, these are 25 seconds at 0H and 35 seconds at 24H and only measured over the three positions. So, if you achieve those and the other requirements shown above, you are in spec and can call it a day. If not, don’t try any dynamic poising, as Al says fix everything else first as likely the problem will be elsewhere. For example, if the pin gap is too large, you will usually see a slower rate in vertical than in horizontal and at 24H, all the rates will be slower. If dial up is much faster than dial down then it could be the pins are not parallel and are closer at the tip. If 3H is much faster than 9H, then it could be your balance spring is not central. There is a lot to interpreting these results so, have a look online for “witschi training manual” and the pdf that you get gives some indications on pages 14 and 15. These are not extensive. Don’t forget that errors can reverse as you go down to low amplitudes such as 160 degrees…. So, you’ve got the movement running as best as you can without touching the balance wheel and now you measure all positions and are in spec. This would be the point to try dynamic poising for me, it gets you a slight improvement but you were already in a good place so, the movement was fine in all other respects. A bit about pin clearances and amplitude and why dynamic poising is done at low amplitudes – typically about 160-180 degrees. Here are some typical graphs showing variations for a few errors that are often seen – don’t pay too much attention to the absolute rate value but, what you’re trying to see here is that it often isn’t clear what the issue is just from the timegrapher. Also, I think it answers some of your questions above as I seem to have waffled on a bit. Like Al says, it might be best to show that you can achieve good results with all “standard” work and adjustments and then start to discuss dynamic poising. I hope this helps and is of interest. It’s not comprehensive at all but should give an idea of where I think you want to be before taking that next step. Regards, Chris