OK so I did some of my own digging and found some info.

The C07 is based on the 2824 with a few optimizations in common. They all have been slowed down from 4Hz to 3Hz. They also all have smaller barrel arbors to accommodate more mainspring, and the mainspring itself is different. And they all have free-sprung balances (not sure what this is) without standard regulators. However, beyond this, there are three different versions with more specific characteristics:

C07.1XX - This version has the above improvements plus a synthetic escapement for lower friction, thus requiring less energy from the mainspring. The "Powermatic 80" movements in the latest Tissot and Certina models are based on this. There's a few different versions based on complications, including day/dates. For some reason, though, those haven't replaced the 2836's in the Tissot line-up (yet).

C07.6XX - This version also has the same common improvements, but comes with a standard jeweled escapement. The Hamilton H-10 and H-40 movements are based on this version.

C07.8XX - This version adds a silicon hairspring. I'm not sure if it has the synthetic or standard escapement. I think the "Powermatic 80 Silicum" and some "Powermatic 80 Chronometer" movements are based on this, which would imply it has the same synthetic escapement, though I could be wrong.


By all means correct me if any of this is wrong.

The other questions still apply.

 

Gee, where do I start?

The C07 movement is based on the ETA 2824-2 with some changes. There are different models of C07 that have better or worse characteristics (or at least I've been led to conclude from other discussions).

I have two Tissot watches, a Seastar and a Luxury with C07 movements. I've had the Seastar for maybe five years now but I keep a handful of watches in rotation so it's seen maybe six months of actual running. I have had no trouble with either watch but they certainly aren't the most accurate in my watch box, maybe gaining 15 s/d in the Seastar's case, more like +5 s/d on the Luxury.

In the case of my C07's, the first difference is the mainspring arbor (and perhaps the mainspring). The arbor is smaller in diameter allowing for more turns on the barrel from unwound to full wind. I can't say how much as I haven't taken either apart yet.

The second is the regulator (balance wheel, hairspring, cock assy.). The rate is 21,600 bph as opposed to 28,800 for an ETA 2824-2. The noticeable difference is that the second hand steps six times per second as opposed to eight, so it's not quite as smooth. The balance is also free-sprung, meaning there are no regulator pins or regulator corrector, only a stud support to attach the outer end of the hairspring. This eliminates the regulator pins as a source of mischief and (potentially) makes the spring more linear, for less amplitude dependent rate variation, one of the causes for positional variation.

Regulation is accomplished via two screws that fit into slots in the balance wheel spokes. The heads have a flat on one side that makes for an imbalance that you can adjust by turning the screw. So a free-sprung balance means there is no regulator corrector to adjust the rate; it's adjusted as I'll describe below.

The third difference (and this is speculation) is the escape wheel is fabricated from silicon, which is supposed to lower the friction, allowing for a higher reduction between the barrel and escape wheel. I haven't verified that this is the case (different ratio) and ETA hasn't published any Tech Sheet so verification would involve disassembly and counting teeth. Some day I will service both but there's no need yet.

All of these changes result in an 80-hour power reserve. I haven't measured the reserve but I can confirm that you can put the watch on the dresser Friday night and it's still running Monday morning.

As I mentioned above, you can make a coarse adjustment by turning the screws. I've read on other posts that it only takes a tiny amount of turning to affect the rate; one poster said that he gave them a nudge and it gained 15 s/d. It appears that the screws sit in slots to allow an even greater range of adjustment but as I've never tried, I can't verify that they even move in the slots, or perhaps the poster was moving them in the slots, resulting in the sensitivity. Since there are only two spokes and two adjustment screws, you cannot use them to adjust poise errors in the perpendicular direction and you have to be careful to make identical adjustments or you will screw up the poise in the parallel direction.

The factory says they use a laser to both poise the wheel and adjust the rate. On my watches (both with display backs) you can see a small short groove on the rim of the balance wheel. I've also read a patent that alludes to calculating the poise and rate error by timing in positions an applying some math. I can't remember who took out the patent but my speculation is this is what they are doing and have established how much laser is needed for a given correction (wouldn't that be a b!+ch to keep in calibration).

As I mentioned at the start, there are flavors of C07. I've heard of and seen drawings of plastic pallet forks that may have come from the System51 development and seen bad reviews of their longevity. Perhaps this is why my watches have traditional forks, because the plastic ones gave ETA a black eye. I've also seen speculation that the hairspring is silicon but I have my doubts due to the cost. Another question is what they lubricate the pallet stones with, see below.

Unless you have a plastic pallet fork, I don't see any dramatic difference in longevity. My weak spot would be the mainspring coiling more tightly, but modern alloy springs can take much more than they are put through in a standard design. Perhaps time will prove men wrong, but I haven't heard of a broken one to this point.

I don't see the C07 replacing the 2824-2, there's too much demand in the industry for it. I see it as a bit player to allow some Swatch companies to differentiate themselves. But both of my examples were very inexpensive (less than $500 GM) so they are certainly not selling it as a luxury item (despite the watches name). I do know that some Tissot models with the C07 are available as COSC, so it's a solid design. Also in the 2824-2, the COSC models have some different parts, glucydur balance wheels, Incabloc shock protectors and monocrystalline pallet stones. One would think that the COSC models of the C07 would have the same changes. My non-COSC C07's have novodiac shock protectors, that's pretty obvious; it's hard to say what the balance wheel is made from as it's dramatically different in design than the 2824-2. I'd have to look at my pallet stones under a microscope to determine if they are mono or poly and that requires uncasing, so no-go.

BTW, poking around the net, I found a good discussion on Watch Repair Talk that had some pictures. I have to qualify the above by stating that I think mine are standard style in the pallet fork and escapement but I'll have to take a hard look under the microscope tonight. Here are a couple of interesting snips from the discussion:

So that answers the lube question, at least for the System51 components. Moebius TH7 can be found at the usual suspects for the usual price.

BTW, after posting I saw the post you put up while I was writing this diatribe. Interesting and I'll have a look at mine to see the reference and what light they shed on your data. From what you wrote, I probably have the plastic version.

 

The balance is also free-sprung, meaning there are no regulator pins or regulator corrector, only a stud support to attach the outer end of the hairspring. This eliminates the regulator pins as a source of mischief and (potentially) makes the spring more linear, for less amplitude dependent rate variation, one of the causes for positional variation.

Regulation is accomplished via two screws that fit into slots in the balance wheel spokes. The heads have a flat on one side that makes for an imbalance that you can adjust by turning the screw. So a free-sprung balance means there is no regulator corrector to adjust the rate; it's adjusted as I'll describe below.

That's the part that probably killed my Powermatic movement.

Just in case my first watchmaker made a mistake was incompetent, I asked a second watchmaker in Hong Kong to take it on. I did not tell him the movement has been to a competitor, only to Swatch HK who did not properly fix it.

The second watchmaker won't even touch it:
Me: I read the Powermatic can be adjusted by adjusting its weights, similar to some Rolex freesprung models (?!).
Me: But it shouldn't have 30 seconds of positional variance
Me: Their tolerance is 30
2nd watchmaker: Rolex has 2 pairs adjustable weights.
Every 90 degrees on the balance wheel.
So they can adjust detail.
2nd watchmaker: But this seems only one pair (180 degree).
So, they can adjust the total fast or slow, but can't adjust the standing position like 3 o'clock up.
Me: Oh. I guess that's why they can fix dial up, but whenever I wear it, it goes haywire and they can't adjust for it
2nd watchmaker: Exactly

I read lots of reports here that plenty of users got good performance out of the box. I don't dispute those.
Mine arrived -8 spd. My mistake was to try and make it better and my first watchmaker didn't know better by helping me try.
These watches are like recent model iPhones - you can't service them outside Apple (Swatch) service chain, and you certainly can't tweak them.

I feel my first watchmaker is a traditionalist Swiss movement snob.
I don't feel the plastic escapement was such a problem (given my Powermatic movement was <1 year old).
But the freesprung balance with only one pair of weights is the maintenance difficulty. So if you happen to have worse-than-expected performance out of the box, there's not much you can really do about it.

Did I mischaracterise where I went wrong with the Powermatic 80? Thoughts welcome.

 

Thanks for explaining the "free sprung" terminology. I knew they all lacked regulator pins, but I wasn't sure if maybe that was just one aspect or if it was just coincidental. It sounds like it pretty much just means no regulator pin, though.

I guess it's encouraging that you can still regulate a free sprung balance, but it sounds like it's far more complicated and risky than the familiar "+/-" lever on standard balances.

And yes, I can see how getting rid of the pin would help with positional variance, so that's a good thing. I guess that helps make up for the sacrifice in precision from the lower beat rate. Enough to earn a Chronometer rating anyway. Are there any other 3Hz Chronometers out there?

I'm an amateur tinkerer at best, so while I'm perfectly comfortable timegraphing and regulating my own watches, I admit the free sprung balance will probably scare me off from buying one. I'd go nuts if I got one of these and it ran at -4spd or something and I couldn't fix it.

 

I'm an amateur tinkerer at best, so while I'm perfectly comfortable timegraphing and regulating my own watches, I admit the free sprung balance will probably scare me off from buying one. I'd go nuts if I got one of these and it ran at -4spd or something and I couldn't fix it.

Other watches have better solutions. Both my Milgauss and my 9300 Omegas have free sprung balances and are adjustable via small nuts on threaded shafts located on the inside of the rim and pointed inward. The major difficulty is affording the special tool, but adjusting them is a breeze. Since there are four, it also allows for adjusting the poise in either axis. BTW, if you were wondering, poise is the location of the CG with respect to the pivot axis. It is complicated by the fact that it needs to include the CG of the hairspring, which moves as the balance moves. Poise affects positional variation in the pendant positions (PU, PD, PR, PL).

 

I took a look at both under the microscope and they are both C07.111 and both have plastic parts. Hard to tell without removing the band. Once the band was off it was pretty obvious even with my cheaters and a 10 plate OptiVisor.

Well, I'll keep that in mind regarding service intervals.

 

Thanks for the explanation of poise. I'm learning a lot in this thread!

Would poise also affect beat error?

 

Would poise also affect beat error?

My understanding of poise is that it has an effect because of the swing or missing swing of a point on the balance wheel. If a wheel has an imbalance and travels through an arc of 180 degrees, then if the imbalance is on the uphill side it will have different effect than if it's on the downhill side. This would affect the beat error, making it swing farther towards the bottom than the top. Keep in mind that what we call amplitude is that from center to one extreme, so a 300 degree amplitude is actually 600 degrees of full travel.

According to the texts, there's an amplitude were poise cancels out, 225 degrees if I remember correctly. However, at this low amplitude, accelerations cause rate errors (looking straight at you, Seiko 7S26) so, at normal amplitudes you have to look at the shadow instead of the substance; the part of the sweep that's missing. If it's located on the top or bottom, it cancels itself but if it's on the upward or downward side, then it affects the beat error (as per my example above) and the rate. Note that this is only an issue in the pendant positions, DU or DD doesn't show any effect.

I know it's hard to grasp, I had to read up and think about it for a while before it hit, and I have a background as a mechanical engineer.

Here's an analogy, much earlier in my career as a manufacturing engineer, we had a vehicle that was spin stabilized and had a solid propellant booster attached to one end. It was centered so the thrust nominally went through the CG, but the mounting surface had to be very square to the spin axis. I asked our dynamics expert where the tolerance came from; wouldn't any error balance out because the spin would average the error? The answer was: the rocket would start burning at some spin theta and stop at another. Unless you could guarantee that the angle would be exactly the same at the beginning and end, there would be some missing or overlapped arc and the net result would be a torque on the vehicle (assuming an error in squareness).

It's that overlap or missing section, in the presence of gravity, that results in poise causing a beat error and an error in rate.

 

The 80 hour ETA movements have generally be a disappointment.
De-rating the frequency; lengthening and weakening the mainspring; use of composite fork/escape to reduce friction to compensate for reduced power...interesting ideas...but at least with earlier ETA PR80 versions, performance and longevity (as related to service) appear to be sacrificed.
Free-sprung balance is a proven technology...it does not make up for the short-comings of the other modifications.
Silicon hairsprings...are the properties of low-cost units consistent enough to be attractive in consumer grade movements....?....maybe or maybe not yet...
If one is not sufficiently active so that the movement is fully powered when removed from the wrist on Friday, it will not be running and reasonably "on-time" when strapped on your wrist on Monday...so what's the point?
I tend to be accuracy and precision motivated...the 80 hour PR ETAs are not there yet for my interests.
Regards, BG

 

If one is not sufficiently active so that the movement is fully powered when removed from the wrist on Friday, it will not be running and reasonably "on-time" when strapped on your wrist on Monday...so what's the point?

So I took the opportunity to see how well one of my two Powermatic 80's did off the wrist over the weekend. The movement is a C07.111 in a Tissot Luxury. I wore it all week and saw a rate of about -7 spd for the entire time I was wearing it.

Returning from work Thursday night at eight, I hacked it against my iPhone, wound it fully and placed it PU for the weekend.

This noon (Sunday) I checked it. It was running and had lost 21 seconds. Right now at seven PM, it's still running and at -20 seconds.

Sure, a one-off observation, but I'd say that it's acceptable performance regarding rate when it gets low in it's reserve. I'll do some more observations and post the results.

Update: It stopped this morning at six-thirty for a total power reserve of 82 hours.

 

I find that the rate error is no worse than many of my elabore ETA 2824-2 or Sellita 200-1 movements. The jury is still out on the plastic components. In the best case, I need to get some 9030 and TH7 before I service. Not sure about replacing the mainspring or barrel but my supplier is pretty crafty; I suspect it's only a matter of time and price.

 

Hi everyone,

I have a question regarding my Hamilton H-10 movement in the Khaki automatic ''Murph''. It makes a clicking sound everytime the rotor moves. It does even if the watch is fully drained of power, so I don't think it's the security over-winding protection mechanism. Is that normal behaviour form this movement? I've never owned one of these before. Thanks a lot in advance.

Stay safe and healthy.

Milo

 

I have a question regarding my Hamilton H-10 movement in the Khaki automatic ''Murph''. It makes a clicking sound everytime the rotor moves.

Just saw your post after an update on my end. It's possible that you are hearing the backwards reverser releasing, but unless you are using a stethoscope, I'm skeptical. More likely a broken tooth in the automatic or a loose automatic module. I'd have it looked at in either case.

 

Another curious observation. A workmate bought his first Swiss Automatic, a Hamilton Khaki with an H-40. I told him once he had it, that I would timegraph it and see how it's doing.

Answer: Very well on rates. Going from memory, on the 1 hour test, it's +4 in DU, +2 in DD and zero in the pendant positions. Not bad at all.

The only curious thing is the amplitude, I did see an occasional spike up to 280 or so, but a typical amplitude was about 240. I was wearing my Tissot Luxury and measured it; resulting in similar performance of about 240. These were DU/DD positions. I'm a little surprised I hadn't noticed this before as I've had the Luxury for several years and the timegrapher almost as long. Can't say I have a good answer for this; my Luxury may be several years old, but his Khaki should be brand new.

 

I had my Tissot Powermatic 80 PR100 regulated. The results weren't good.

Before: -8spd in all positions

After:
CH (dial up): +6
9H (crown down): -3
6H (crown left): +2

My watchmaker's comments:
1. Plastic escapement
2. Grime inside

I was a bit surprised at the grime. Although I got this Tissot as part of a product exchange with Swatch HK, I was told the exchanged watch was new and my paperwork has no indications to the contrary.

The watchmaker noted no suggestion this watch was a replacement unit in the watch itself, even though I noted the bracelet was stamped "RTO".

But the watchmaker had lots to say about plastic escapements. Essentially saying their were a POS in Cantonese. He claimed he was told reliably by insider that Swatch HK treats the movement as disposable.

 

I had my Tissot Powermatic 80 PR100 regulated. The results weren't good.

Before: -8spd in all positions

After:
CH (dial up): +6
9H (crown down): -3
6H (crown left): +2

The watchmaker regulation failed.
I had the following data points (daily rates):
9H: -39.1spd, -42.7spd
CH: -18.4spd, -20.3spd

My Timegrapher app had the watch go -35 spd and the plot scatter all over the place.

Since this exceeded Tissot's "average accuracy tolerance" of -10/+30 https://www.tissotwatches.com/assets/usermanuals/157-en.pdf , I made a warranty claim on Tissot (Swatch HK).

Swatch HK repair department informed me:

• the warranty claim was accepted
• per their assessment, the movement was in acceptable working order
• therefore they carried out a "time rate service" to my watch.

All this done within three days.
They did not pick up my external regulation of the watch.

Watchcheck app now has the watch go -7.8spd over three days

I am not at all impressed by the C07 movement. It will be a see and avoid movement for me.

On the other hand I'm really impressed by my ETA 2893-2 Christopher Ward accuracy . It's still going at -0.6spd for a week. I'd go with those from now on....

 

Does anyone out there have an idea of the lift angle of a C07 with the plastic pallet fork? Calibre Corner says "Unknown". I'm wondering if that's the reason for the low amplitude.

OTOH, my friend with a H-40, which is supposed to have a normal pallet fork, also measured a 240 lift angle in DU/DD. Perhaps it's a side-effect of the longer battery.

 

...OTOH, my friend with a H-40, which is supposed to have a normal pallet fork, also measured a 240 lift angle in DU/DD. Perhaps it's a side-effect of the longer battery.

Not quite fully awake and recalling a dream? Maybe you need another cup of coffee?
Regards, BG

 

Aww, come on, now you guys are just being mean.

 

OK, now I get the joke. I have been using Roland Ranffts bidfun database and saw "mainspring / battery", thinking they were synonymous. I also thought that I had read the term battery referring to the power source for a mechanical in other archaic sources but googling and looking through my books, I realize I was mistaken (when has that ever happened?).

The funny thing is, I've never looked up a quartz movement in his database so I never saw that the "mainspring / battery" field contains and actual battery. Duh.

See how well my signature matches? (You can thank me that you can read my signature).

 

^^^ OK, I'll bite.

My dreams rarely involve watchmaking but are often much nerdier. The coffee is an essential. The second or third cup, not so much.

Regarding the measurement, I was quite surprised it was so low (I followed the protocol about a full wind and running for an hour), so I checked it several times and also measured my own C07 I had been wearing at the time and got similar results (after following protocol).

I was just curious what the cause of the low amplitude is. I would expect it on my several-years old Tissot Seastar but not on his new H-40. One explanation would be that the mainspring isn't as strong (likely to be true, if not the cause, IMHO) or that the lift angle is something other than 50 degrees.

It would sure be nice if ETA put out some technical information on the movement; I know that those with a Swatch account have it because I've seen some screen snips.

I was hoping someone with access would just tell us the lift angle of the C07.111 based on ETA's documentation. Looking at the plastic pallet fork, I would be very surprised if it matched the 2824-2 lift angle.

 

Why don't you use your TG to determine an approximate lift angle?

 

Because of:
LA = Life Angle
A = Amplitude
R = Reading
F = Scaling factor

R = f(LA,A) where the function is unknown (although pretty close to inverse, maybe completely)

Lets assume inverse, so.
R = F * (A / LA)

I need to know two of the values to solve for the third. I know the Reading. I can derive the Scaling Factor from measurements on watches of known lift angle. I don't know the Lift Angle for this particular watch. I cannot derive it from the knowns.

I've also considered measuring the actual amplitude on a TAG Link Chrono with a 2894-2 using a GoPro set to capture at 240 fps and examining the frames. Haven't done that yet, but that experiment would give me the missing variable above.

 

I've also considered measuring the actual amplitude on a TAG Link Chrono with a 2894-2 using a GoPro set to capture at 240 fps and examining the frames. Haven't done that yet, but that experiment would give me the missing variable above.

That's how you do it. No need to make it more complicated than that. Wind the watch until you observe 180 degrees of amplitude (verified using phone camera in slow motion) then set lift angle so amplitude reads 180 and you are done...

 

BTW, I had a chance to identify the movement in the H-40 noted above. It's a C07.641 and has a standard escapement.

The other oddity are the shock protectors. They have three "tee" shaped fingers sticking inward from a round rim. The cock has three notches around the perimeter of the hole it fits in so you would turn it to release it. I didn't see a split anywhere so I doubt you could pry it out. It's just odd to me because I haven't seen anything like it in a modern watch.

 

^^^ Thanks for distilling it so well.

I had considered this regarding my Omega 9300's. Obviously, 38 degrees doesn't equate to a decent amplitude so is there a lift angle setting that does? I realize that the sound trace on a co-axial is different and I might be chasing my tail, but there might be some hope in this angle of study.

I am also familiar of non-linearities so it's important to capture it at least two different magnitudes and even then, it's possible to get lucky and get the two points where reality and theory cross.

You should see the nasty formula for thermistor temperature dependent resistance. We deal with it with a calibration table, easier than running the math.

 

You are really overcomplicating it...amplitude isn't a measure that requires a really high resolution to get an absolutely accurate number, so as long as you are reasonably close on the lift angle, you are fine. For example if the amplitude in horizontal positions is say 290 or 296, it makes no material difference to what I do next on the watch, as either of those numbers are good. Amplitude is not used in a way that requires a really high degree of absolute accuracy.

On the co-axial watches, unless the timing machine has a specific program that you set to measure co-axial amplitudes, it will not accurately measure them no matter what lift angle setting you use. I had a very long email conversation with the engineers at Witchsi regarding measuring co-axial amplitudes, because initially my timing machine was giving me very erratic readings on these watches. My machine was sent back for an update to the software and calibration (it was an early one of this specific model) and there are challenges with this due to the close proximity of some sounds. They described it as "not easy" and if you know the Swiss, that means it's very difficult...

Just so you know, co-axial watches in general do tend to have lower amplitudes than lever escapement watches do.

Cheers, Al

 

Thank you so much for your in-depth reply. I'm not being a kiss-ass (well, maybe not) but the entire community owes you a great deal of gratitude for the trouble you take to respond to the "kids in the cheap seats" (quoting Maillchort).

I was going through my old emails and discovered this interesting missive. I actually didn't see it on OF when it was posted:

Thank you very much, keepitsimple, for posting the traces! My microphone (part of a headset) is not good enough to disentangle any details of the tic and toc of my Omega 9300.

Expiredwatchdog, I would expect the acoustic signals from the clockwise and counterclockwise half-oscillations ( 'tic' and 'toc', or left and right in your post) of the 8500 movement to be different since the impulse transfer is via different paths: I assume the left/first one with the four events/spikes is the indirect transfer via the lever, so (all guessing on my part, maybe your Witschi manual has specifics?) the first small pulse is the roller hitting the lever immediately followed by unlocking, the second is the tooth of the impulse wheel hitting the impulse pallet of the lever, the third right after is the lever hitting the roller (completing the impulse transfer to the balance), and the fourth is the locking and the lever hitting the bank (not sure about the order there, probably the lever hits the bank before the escape wheel tooth locks on the pallet).

Regarding fooling the timing machine, Omega specifies that for version A of the 2403 you should set your older Witschi machine to 30 degree lift angle, and for version B to 38 (according to http://www.phfactor.net/wtf/Omega/1831_Omega2403,2403A,2403B.doc.pdf), but for newer machines using 38 in both cases is correct.

Naively just taking the distance from the first to the last event (which agree for 'tic' and 'toc' in all three cases) in relation to the half-oscillation length, and using 51 degree lift angle for the Certina, and 38 for the Omegas, I obtain amplitudes of 216 (Certina), 290 (2403) and 207 (8500) degrees. Keepitsimple, would you happen to know the true amplitudes going with these traces?

In any case, seeing the traces is really great!

Yeah, I suspect that a relative test compared to some older tests would be all I really need; the SMPO is likely within it's warranty (though it was purchased GM for about half price) so it would probably be a good standard, with the lift angle set at either setting. Then it's just a matter of comparing today's results against those of the future and I do keep a log book.

Thanks again
Dave

 

First time I see up close photos of the plastic escapement parts and I understand why it is a movement to avoid. It also lack a regulator arm ?

Nice idea of using that CK 2824 to remplace the movement as it seems finished very nicely for cheap (price seems the same as a 2824 movement by itself but include everything else).

 

It also lack a regulator arm ?

Yep

The first night performance is -4.7spd

 

Owning two Powermatic 80s, I would consider being happy with your present performance. They are not precision instruments.

Yes, they can be tuned to reasonable performance (I don't have the specs as ETA doesn't publish any data to us pedants) but I feel that it shouldn't be any worse than a 2824-2 elabore grade. Plus or Minus 20 per day is acceptable. Want worse, buy any Seiko with a 7S26 (or many other asian counterparts).

 

Need to answer your comments out of order:

Yes, they can be tuned to reasonable performance (I don't have the specs as ETA doesn't publish any data to us pedants)

No, I disagree. Maybe I don't have access of sufficient knowledge of better watchmakers in this city - this city is so hardcoded to the authorised repair system - that one botched it and another won't touch it.

But then again, I wouldn't regard the watchmaker I'm using is a duffer given he's done all the other repairs I gave him listed above more than satisfactorily. If another WUS member reading this is contemplating tuning or regulating a Powermatic 80, I seriously suggest they ask the watchmaker have they any experience with this movement before.

Owning two Powermatic 80s, I would consider being happy with your present performance. They are not precision instruments.

...I feel that it shouldn't be any worse than a 2824-2 elabore grade. Plus or Minus 20 per day is acceptable.

I'm a bit of a tweaker. I don't accept any watch outside chronometer standards lying down. If I had to leave the Powermatic 80 at -8spd it'd just gather dust. Or I'd sell it.
So I guess, on retrospect, the movement change had to happen. The only thing I shouldn't have done was to attempt to regulate it first.

Want worse, buy any Seiko with a 7S26 (or many other asian counterparts).

My SNKL23J1 was -3.3spd, my wife's SNKL19K1 was -6.8spd and Parnis DG3804 GMT +3.2spd out of the box. Just put them on the timegrapher, the SNKL23J1, SNKL19K1 and Parnis GMT are now +2spd, +4spd and +4spd respectively.

 

Good job diynor_77!
Haven't regulated one yet as it seems to be a very time consuming process and the risk of causing a damage is still very high for a non professional like me. I have a question for the professionals here. How do you move the two balance weights exactly the same distance from center? My guess is their positions are originally fixed by laser beams, how is this done by visual measure? Is equal distance from the center that important for timing or it doesn't matter as long as timing is within desired sec/day?
Sorry if this is a stupid question, I have no experience with these.
Ivan

 

I have a question for the professionals here. How do you move the two balance weights exactly the same distance from center? My guess is their positions are originally fixed by laser beams, how is this done by visual measure? Is equal distance from the center that important for timing or it doesn't matter as long as timing is within desired sec/day?

The tool used for the adjustments that is available from Tissot has a graduated scale on it that aids in moving the screws the same amount. This is similar to what you would find on a Rolex style Microstella tool, or an Omega tool for moving their balance rim weights.

But in the end, if you see a poise error introduced that wasn't there before, you know you didn't move them the same amount. So yes it is important to move them the same. If you do a lot of this work it's not a big deal really.

Cheers, Al

 

It seems that, logically, trying different lift angles until you get the minimum beat terror would give you a good guide to the actual lift angle.

 

Would it not be reasonable to empirically adjust the lift angle till you have the minimum beat error and take that as a guide to your lift angle.

 

I've measured my Captain Cook, which runs this movement, using a lift angle of 62 degrees, and the watch runs within COSC parameters in all positions with an amplitude of between 290 and 330, a rate between 0 and +6 sec, and a beat error between 0.2 and 0.3 milliseconds. It might be worth trying to run your C07.611 on a timegrapher with around 62 degrees set as the lift angle.