rkovars wrote: ↑Thu Jun 20, 2024 4:10 pm I am the first to stand up and voice concerns over CWs current service policies (and have in several threads and also personal experience) but there are a few things here that I think are worth discussing and food for thought.

You are conflating two different terms here: accuracy and rate. The watch is running at a rate of -2 spd but may still be very accurate. Accuracy is a measurement of how well the watch stays around that rate.

Measurements are tricky. We, as hobbyists, don't have the best equipment or controlled testing environments. Therefore we do the best we can. Because of this, I use my timegrapher etc as 'guides' and on wrist measurements as a real guide. I use the WatchTracker app to make my on wrist measurements largely because I am a little to lazy to do it myself with a spreadsheet etc. It does make a difference. I have one watch that runs -1 spd on average when static. It runs at 0.8 spd when on wrist without fail over several timing runs. You are also only as accurate in your measurements as your equipment. The ubiquitous Weishi is great for hobbyists given the price point but it is far from a claibrated piece of equipment. Measurements can vary over time and shouldn't be taken as gospel for any given measuring period. They are great for measuring trends over time and for doing quick and dirty regulation. Movements will also show different readings under different conditions. I don't know about you, but I am not making my measurements in a strict temperature/humidity controlled environment. Again these can cause drift in measurements. A final thought on measurements, I typically average out 6 positions on my COSC movements. This is really the most accurate way to get a picture of what a watch will do on the wrist. 1 measurement dial up gives you only part of the picture in reality. It can also tell you the best position to leave the watch when not wearing it so that you get the most 'self' regulation each day.

Watch movements are not a static system and are constantly changing. I would not expect a watch to run exactly the same after being shipped, opened and parts changed (no matter what those parts are) and shipped back to me. A lot can change in that evolution. Especially with the regulation. With regulation, the adjustments to be made between +1 and -2 are not even perceptible to the human eye. This is one of the reasons Omega developed their new Spirite system. A final thought on regulation, the SH21 will suffer from the same trouble every movement of this type does - regulation may drift over time because the regulation arms move. They aren't fixed. This is one of the reasons the free sprung balance was developed. Free sprung balances have a better track record of holding regulation over time. The truth is, they may have done exactly what you asked - not touching the regulation. If you hadn't requested that they may have tweaked it a bit before sending it back. My local go to watch maker likes to have them slightly fast when going out the door. There is really no way to tell. I will say that I really doubt it is a different movement. The differences in rate are very small in your measurements. Let alone the cost of an entire movement over servicing the auto-winding system (I can't verify this for 100% but given CWs price conscious nature I doubt they did a swap).

One part that cannot be disputed is the box. You should have gotten the original box back. Although, industry wide this is not atypical. A lot of companies will not ship the watch back in the same container. They will discard the incoming packaging. I never send in anything I want to keep. It shouldn't be that way but it is what it is. CW is big enough now that these little touches may be a thing of the past I am afraid.

I know that this watch was a struggle out of the gate with all of the delays and that everything since has just thrown more wood on the fire.

If it were me, I would wear the watch for a couple of weeks straight keeping track of the time keeping ideally with an app. The benefit of the app is that you don't have to mark the time at regular intervals etc. You just check in at your leisure and it does the math for you. This will average out all of the stuff that taking measurements with a machine does not. I would wager that it will run very accurately over the period and won't drift. The rate may or may not surprise you based on your initial measurement. If the rate is not exactly where you want it, you could investigate further where the trouble is by measuring over several positions and ultimately maybe having someone regulate more to your liking (someone local that you trust or CW - that would be your choice).

Like I said, I know this has been a struggle from the beginning with the delays. I am not sure I would be too concerned with a chronograph offering though as the supply chain for the movement would be completely different. Another SH21 would be a different story although a lot has changed in the last year for the SH21. CW purchasing a stake in a manufacturer should help eliminate delays like they had with the C63s (I should note here that I don't have any inside knowledge outside of what I can glean publicly from CW documentation and interviews).

Redpat wrote: ↑Fri Jul 19, 2024 11:01 pm I'm glad it all seems to have levelled out and working pretty much as it should. I think I'm probably overthinking it. At the end of the day CW must have built a fair few thousand products utilising the sh21 and only a handful seem to have had any issues. I will cross my fingers and just try and enjoy my bmf. After all, there is a 5 year warranty and from what I've learned since joing the forum is that cws customer service is pretty good these days.
Thanks for the update
Pat

Chris GB wrote: ↑Fri Jul 19, 2024 11:41 pm

rkovars wrote: ↑Thu Jun 20, 2024 4:10 pm I am the first to stand up and voice concerns over CWs current service policies (and have in several threads and also personal experience) but there are a few things here that I think are worth discussing and food for thought.

You are conflating two different terms here: accuracy and rate. The watch is running at a rate of -2 spd but may still be very accurate. Accuracy is a measurement of how well the watch stays around that rate.

Measurements are tricky. We, as hobbyists, don't have the best equipment or controlled testing environments. Therefore we do the best we can. Because of this, I use my timegrapher etc as 'guides' and on wrist measurements as a real guide. I use the WatchTracker app to make my on wrist measurements largely because I am a little to lazy to do it myself with a spreadsheet etc. It does make a difference. I have one watch that runs -1 spd on average when static. It runs at 0.8 spd when on wrist without fail over several timing runs. You are also only as accurate in your measurements as your equipment. The ubiquitous Weishi is great for hobbyists given the price point but it is far from a claibrated piece of equipment. Measurements can vary over time and shouldn't be taken as gospel for any given measuring period. They are great for measuring trends over time and for doing quick and dirty regulation. Movements will also show different readings under different conditions. I don't know about you, but I am not making my measurements in a strict temperature/humidity controlled environment. Again these can cause drift in measurements. A final thought on measurements, I typically average out 6 positions on my COSC movements. This is really the most accurate way to get a picture of what a watch will do on the wrist. 1 measurement dial up gives you only part of the picture in reality. It can also tell you the best position to leave the watch when not wearing it so that you get the most 'self' regulation each day.

Watch movements are not a static system and are constantly changing. I would not expect a watch to run exactly the same after being shipped, opened and parts changed (no matter what those parts are) and shipped back to me. A lot can change in that evolution. Especially with the regulation. With regulation, the adjustments to be made between +1 and -2 are not even perceptible to the human eye. This is one of the reasons Omega developed their new Spirite system. A final thought on regulation, the SH21 will suffer from the same trouble every movement of this type does - regulation may drift over time because the regulation arms move. They aren't fixed. This is one of the reasons the free sprung balance was developed. Free sprung balances have a better track record of holding regulation over time. The truth is, they may have done exactly what you asked - not touching the regulation. If you hadn't requested that they may have tweaked it a bit before sending it back. My local go to watch maker likes to have them slightly fast when going out the door. There is really no way to tell. I will say that I really doubt it is a different movement. The differences in rate are very small in your measurements. Let alone the cost of an entire movement over servicing the auto-winding system (I can't verify this for 100% but given CWs price conscious nature I doubt they did a swap).

One part that cannot be disputed is the box. You should have gotten the original box back. Although, industry wide this is not atypical. A lot of companies will not ship the watch back in the same container. They will discard the incoming packaging. I never send in anything I want to keep. It shouldn't be that way but it is what it is. CW is big enough now that these little touches may be a thing of the past I am afraid.

I know that this watch was a struggle out of the gate with all of the delays and that everything since has just thrown more wood on the fire.

If it were me, I would wear the watch for a couple of weeks straight keeping track of the time keeping ideally with an app. The benefit of the app is that you don't have to mark the time at regular intervals etc. You just check in at your leisure and it does the math for you. This will average out all of the stuff that taking measurements with a machine does not. I would wager that it will run very accurately over the period and won't drift. The rate may or may not surprise you based on your initial measurement. If the rate is not exactly where you want it, you could investigate further where the trouble is by measuring over several positions and ultimately maybe having someone regulate more to your liking (someone local that you trust or CW - that would be your choice).

Like I said, I know this has been a struggle from the beginning with the delays. I am not sure I would be too concerned with a chronograph offering though as the supply chain for the movement would be completely different. Another SH21 would be a different story although a lot has changed in the last year for the SH21. CW purchasing a stake in a manufacturer should help eliminate delays like they had with the C63s (I should note here that I don't have any inside knowledge outside of what I can glean publicly from CW documentation and interviews).

Apologies for not replying to this before, I somehow missed it!

For me, accuracy in a watch is how the output (displayed time) matches the measured commodity (reference time). So a watch that loses a second a day will be "inaccurate" by that amount at the end of day one. If it consistently stays running at that rate, it will have a linear inaccuracy of +1spd pd.

Repeatability is for me, the ability of the watch to keep the same rate. So if it runs consistently at +1spd, we have repeatability and linearity. If the rate is variable, we have non linear inaccuracy, making the instrument less predictable in it's error level.

I think a major part of why I'm interested in mechanical watches is my love of all things science and engineering. Over my career, I've found myself deeply involved in the science of tribology (a major factor in how a watch runs, I'm sure). Also, precision measurement, I ran a multi discipline calibration lab for a year or so, and subsequently used some very high accuracy and high sensitivity measuring and weighing equipment in a research establishment. The statistical techniques in these precision measurements are very well suited to adaptation in quantifying watch performance!

You want to try making accurate measurements of things down to 0.0000001g. You've got basic accuracy, drift, atmospheric pressure buoyancy variation, temperature sensitivity, temperature sample up or down draft sensitivity, humidity sensitivity, vibration sensitivity. Oh and at 0.00001g, you are in reality using a very sensitive seismograph which can be unusable if somewhere on the planet has had an earthquake in the last day or so. Add a couple more zeros, you get the idea

It's the interplay of variabilities that make watch mechanisms fascinating to me. I'm looking forward to having the time to start poking around in the mechanism of a cheap watch and start looking at ways to "tune them up" for better than factory performance. Optimist, I know! It will probably end in .

JAFO wrote: ↑Sat Jul 20, 2024 9:46 am

Chris GB wrote: ↑Fri Jul 19, 2024 11:41 pm

rkovars wrote: ↑Thu Jun 20, 2024 4:10 pm I am the first to stand up and voice concerns over CWs current service policies (and have in several threads and also personal experience) but there are a few things here that I think are worth discussing and food for thought.

You are conflating two different terms here: accuracy and rate. The watch is running at a rate of -2 spd but may still be very accurate. Accuracy is a measurement of how well the watch stays around that rate.

Measurements are tricky. We, as hobbyists, don't have the best equipment or controlled testing environments. Therefore we do the best we can. Because of this, I use my timegrapher etc as 'guides' and on wrist measurements as a real guide. I use the WatchTracker app to make my on wrist measurements largely because I am a little to lazy to do it myself with a spreadsheet etc. It does make a difference. I have one watch that runs -1 spd on average when static. It runs at 0.8 spd when on wrist without fail over several timing runs. You are also only as accurate in your measurements as your equipment. The ubiquitous Weishi is great for hobbyists given the price point but it is far from a claibrated piece of equipment. Measurements can vary over time and shouldn't be taken as gospel for any given measuring period. They are great for measuring trends over time and for doing quick and dirty regulation. Movements will also show different readings under different conditions. I don't know about you, but I am not making my measurements in a strict temperature/humidity controlled environment. Again these can cause drift in measurements. A final thought on measurements, I typically average out 6 positions on my COSC movements. This is really the most accurate way to get a picture of what a watch will do on the wrist. 1 measurement dial up gives you only part of the picture in reality. It can also tell you the best position to leave the watch when not wearing it so that you get the most 'self' regulation each day.

Watch movements are not a static system and are constantly changing. I would not expect a watch to run exactly the same after being shipped, opened and parts changed (no matter what those parts are) and shipped back to me. A lot can change in that evolution. Especially with the regulation. With regulation, the adjustments to be made between +1 and -2 are not even perceptible to the human eye. This is one of the reasons Omega developed their new Spirite system. A final thought on regulation, the SH21 will suffer from the same trouble every movement of this type does - regulation may drift over time because the regulation arms move. They aren't fixed. This is one of the reasons the free sprung balance was developed. Free sprung balances have a better track record of holding regulation over time. The truth is, they may have done exactly what you asked - not touching the regulation. If you hadn't requested that they may have tweaked it a bit before sending it back. My local go to watch maker likes to have them slightly fast when going out the door. There is really no way to tell. I will say that I really doubt it is a different movement. The differences in rate are very small in your measurements. Let alone the cost of an entire movement over servicing the auto-winding system (I can't verify this for 100% but given CWs price conscious nature I doubt they did a swap).

One part that cannot be disputed is the box. You should have gotten the original box back. Although, industry wide this is not atypical. A lot of companies will not ship the watch back in the same container. They will discard the incoming packaging. I never send in anything I want to keep. It shouldn't be that way but it is what it is. CW is big enough now that these little touches may be a thing of the past I am afraid.

I know that this watch was a struggle out of the gate with all of the delays and that everything since has just thrown more wood on the fire.

If it were me, I would wear the watch for a couple of weeks straight keeping track of the time keeping ideally with an app. The benefit of the app is that you don't have to mark the time at regular intervals etc. You just check in at your leisure and it does the math for you. This will average out all of the stuff that taking measurements with a machine does not. I would wager that it will run very accurately over the period and won't drift. The rate may or may not surprise you based on your initial measurement. If the rate is not exactly where you want it, you could investigate further where the trouble is by measuring over several positions and ultimately maybe having someone regulate more to your liking (someone local that you trust or CW - that would be your choice).

Like I said, I know this has been a struggle from the beginning with the delays. I am not sure I would be too concerned with a chronograph offering though as the supply chain for the movement would be completely different. Another SH21 would be a different story although a lot has changed in the last year for the SH21. CW purchasing a stake in a manufacturer should help eliminate delays like they had with the C63s (I should note here that I don't have any inside knowledge outside of what I can glean publicly from CW documentation and interviews).

Apologies for not replying to this before, I somehow missed it!

For me, accuracy in a watch is how the output (displayed time) matches the measured commodity (reference time). So a watch that loses a second a day will be "inaccurate" by that amount at the end of day one. If it consistently stays running at that rate, it will have a linear inaccuracy of +1spd pd.

Repeatability is for me, the ability of the watch to keep the same rate. So if it runs consistently at +1spd, we have repeatability and linearity. If the rate is variable, we have non linear inaccuracy, making the instrument less predictable in it's error level.

I think a major part of why I'm interested in mechanical watches is my love of all things science and engineering. Over my career, I've found myself deeply involved in the science of tribology (a major factor in how a watch runs, I'm sure). Also, precision measurement, I ran a multi discipline calibration lab for a year or so, and subsequently used some very high accuracy and high sensitivity measuring and weighing equipment in a research establishment. The statistical techniques in these precision measurements are very well suited to adaptation in quantifying watch performance!

You want to try making accurate measurements of things down to 0.0000001g. You've got basic accuracy, drift, atmospheric pressure buoyancy variation, temperature sensitivity, temperature sample up or down draft sensitivity, humidity sensitivity, vibration sensitivity. Oh and at 0.00001g, you are in reality using a very sensitive seismograph which can be unusable if somewhere on the planet has had an earthquake in the last day or so. Add a couple more zeros, you get the idea

It's the interplay of variabilities that make watch mechanisms fascinating to me. I'm looking forward to having the time to start poking around in the mechanism of a cheap watch and start looking at ways to "tune them up" for better than factory performance. Optimist, I know! It will probably end in .

What's a "g" Chris? Is it a gram weight, or a linear measurement?

Better than factory? I think factories make a standard movement that gives, say, the +-20spd without any manual regulation, which is how they make them relatively cheaply. So tiny errors in component size and positioning will affect the movement accuracy. So no doubt a user can improve the accuracy of an individual movement that happens to be an outlet, with a bit of time and care.(And understanding;)

I saw a video the other day talking about the manufacturing tolerances of silicon being so much better than steel. On that basis watch movements can/could be made more precise in manufacturing accuracy, giving rise to a better standard movement, by using materials other than steel and so on, and being able to laser parts etc to a much tighter precision. I think the author thought it might reduce the charm of watch movements, but I'm not so sure. I can't remember who it was though. I will try to find it again.

Chris GB wrote: ↑Fri Jul 19, 2024 11:41 pm
Repeatability is for me, the ability of the watch to keep the same rate. So if it runs consistently at +1spd, we have repeatability and linearity. If the rate is variable, we have non linear inaccuracy, making the instrument less predictable in it's error level.

Chris GB wrote: ↑Fri Jul 19, 2024 11:41 pm The statistical techniques in these precision measurements are very well suited to adaptation in quantifying watch performance!

JAFO wrote: ↑Wed Jul 24, 2024 3:02 am Given they can pretty well tell how a whole nation voted at an election, from talking to a relative handful of people, statistical analysis is definitely pretty accurate.

JAFO wrote: ↑Wed Jul 24, 2024 3:02 am You can see the scatter graph appearing with the watch accuracy meter. As long as the mic can hear it ok, the trace is generally very linear.

rkovars wrote: ↑Wed Jul 24, 2024 3:03 pm

JAFO wrote: ↑Wed Jul 24, 2024 3:02 am Given they can pretty well tell how a whole nation voted at an election, from talking to a relative handful of people, statistical analysis is definitely pretty accurate.

This is a misconception that a lot of people have about polling. They don't predict outcomes. They calculate the probablility of an outcome which is a completely different thing. It is more akin to playing poker or rolling dice. The statistics around measurements are different.

JAFO wrote: ↑Wed Jul 24, 2024 3:02 am You can see the scatter graph appearing with the watch accuracy meter. As long as the mic can hear it ok, the trace is generally very linear.

As long as nothing is wrong. It is still a snapshot during limited conditions (i.e. one position etc).

JAFO wrote: ↑Wed Jul 24, 2024 3:41 pm

rkovars wrote: ↑Wed Jul 24, 2024 3:03 pm

JAFO wrote: ↑Wed Jul 24, 2024 3:02 am Given they can pretty well tell how a whole nation voted at an election, from talking to a relative handful of people, statistical analysis is definitely pretty accurate.

This is a misconception that a lot of people have about polling. They don't predict outcomes. They calculate the probablility of an outcome which is a completely different thing. It is more akin to playing poker or rolling dice. The statistics around measurements are different.

JAFO wrote: ↑Wed Jul 24, 2024 3:02 am You can see the scatter graph appearing with the watch accuracy meter. As long as the mic can hear it ok, the trace is generally very linear.

As long as nothing is wrong. It is still a snapshot during limited conditions (i.e. one position etc).

An exit poll suggests the expected result within a margin of error, as you said. How is that not predicting the outcome? In very close cases that might be inaccurate. In the UK general election in this month they predicted a landslide win for labour, and that was the result. They got some details wrong.

My understanding is that the TV networks in the USA call the election (individual states) based on their own statistical analysis of the results, before the votes are counted, and before voting had even completed across the USA. This may have caused some very close elections to be declared wrongly as a result.

nathanc17 wrote: ↑Wed Aug 21, 2024 5:07 am I’m close to purchasing my first CW. From watch forums this seems to be a worsening problem, it probably won’t change my decision but it’s something for the brand to improve on. But I guess as CW continue to scale the quality control is getting harder and harder.

PGR101 wrote: ↑Wed Aug 21, 2024 11:57 am Interesting to hear some of the comments on the SH21. I have the C65 Trident Bronze LE and the power reserve isn't great and it can only be wound with the crown pushed in, not at first position. And it takes quite a few turns before the second hand starts going.