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Need help with next steps for my 6497 project


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Going through Marks course, I stripped, cleaned, reassembled and lubricated my Seagull ST36.

I then tested the movement in 6 positions. The initial amplitude was quite low. 184 to 211.  I let the watch run overnight.

When I retested the watch in the morning, the amplitude was quite high, 329, so I demagnetized, regulated the movement and retested in 6 positions.

Here are my current results:

Position          Rate          Amplitude          Beat Error

DD                  +5               247                      0.0  

DU                  +3               252                      0.0  

CD                  -11              224                      0.0  

CU                  -3                219                      0.0  

CL                  -10              220                      0.1 

CR                  -3                222                      0.1 

I'm certain my first lubrication job was not the best.  I would like to get the amplitude above 270.

What should be my next steps?  Should I just continue to strip, clean, reassemble and lubricate until my desired amplitude is achieved?

Does the table above indicate where I should focus my attention?

How much should the amplitude and rate change as the movement rests. Currently the movement is running +3 sec per day with 251 amplitude in Dial Up position.

Thanks in advance for your hellp.

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I got a hunch you will see high amplitute if you let it run overnight again and that it is a  low quality new movement, furthurmore, TG would show parrallel graphs for retests.

Cost free to check.

Needless to say, enhance amplitute is generally obtainable through suitable lubrication of the escapement, by suitable I mean to include "amount" of the lubricant. 

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10 hours ago, caseten said:

The initial amplitude was quite low. 184 to 211.  I let the watch run overnight. When I retested the watch in the morning, the amplitude was quite high, 329,

It was 165 but the Chinese machine doubled it, as sometime happens when under 200.

Quote

I'm certain my first lubrication job was not the best.  I would like to get the amplitude above 270.What should be my next steps?  Should I just continue to strip, clean, reassemble and lubricate until my desired amplitude is achieved?

Personally I would call it fine and move on with other mov's but if you feel the urge consider inspecting all jewels and pivots under a microscope, using less oil, use 9415 on the pallets, and polish the inner side of the pallets where the impulse jewel touches. The latter is certainly too advanced for a beginner but fair to mention.

Edited by jdm
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12 hours ago, caseten said:

I would like to get the amplitude above 270

Why do you want to have 270° and is It in one particular position or would you like it in all the positions?

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In the Watch Repair Lessons course, Mark states that the amplitude of a freshly serviced watch should be between 270 and 320. I'm trying to achieve a semi-optimal result.

Sent from my SM-G975U using Tapatalk

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@jdmThanks for the detailed advice.  Yes, I think I will move on. I have a 2836 I will tear down and reassemble, per the nobswatchmaker guide, and then move on to my Seiko NH35As. My goal is to gain proficiency, such that I am able to regulate the NH35A and ETA 2836 and ETA 2824 to a chronometer grade.  I'm particularly interested in the NH35A as they can be had cheaply, and from what I've been told from at least one master watchmaker, the Seiko movements are robust in the way that Rolex calibers are robust. If I can consistently service the NH35A to a chronometer grade, I will be very happy.

BTW this morning the Seagul ST36 movement is operating at -1 s/d 211 amp and 0.0ms beat error dial up.

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3 hours ago, caseten said:

In the Watch Repair Lessons course, Mark states that the amplitude of a freshly serviced watch should be between 270 and 320. I'm trying to achieve a semi-optimal result.

this is a nice specification that Mark has specified. A better specification would be to follow what the watch companies specify.

as your watch is a clone of a Swiss watch I'm going to use their timing specifications this would be for 6497/98 – 2.  But before we get the specification remember your movement is a Chinese clone we don't know how well they manufactured. So to get your maximum amplitude everything has to be really good and of course the watch has to been manufactured to proper specifications. You need to check every single pivot and jewel as stated above by jdm. another place were going to have timing differences of the Chinese versus the Swiss is we don't know how well the Chinese manufacture their mainspring. 

one of my amusements with this group is Mark's example above amplitude you'll continuously see everyone's concerned about amplitude where as if you fix watches for customers they're usually concerned about something different like timekeeping. Watch manufacturers are concerned about timekeeping with a tiny bit of amplitude.

various watch companies put their timing specifications in a variety of locations. Rolex actually has it specified in their service sheets. Omega puts it in a separate instruction sheet. ETA puts it in the manufacturing information sheet which I'm attaching so you can see it for reference and I'm going to snip out some things and attach those.

as far as amplitude goes the watch companies are concerned about a maximum too much is bad typically for most watches at 300°. Then they are concerned about amplitude at the end of 24 hours running. Typically it's 200°. but as not entirely written in stone some companies like Omega will accept a lower amplitude for certain watches as long as the watch still keeps time.

then for your example it's always good  always timer watch in six positions it makes it much easier to find problems. But remember that the manufacturer usually does not specify six positions unless it's a chronometer grade watch. Even Rolex only times in five positions. So this watch is a three position watch.what would've been interesting to see is providing your movement is brand-new as it's a Chinese clone I assume it was it would've been nice to run timing on the brand-new movement versus what happens after you service. As after should always be better than before.

 

 

 

eta st36 time B.JPG

st36 or eta 6497- timing.JPG

ETA 6497-2 Manufacturing Information.pdf

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@JohnR725Thanks for taking the time to write such a thoughtful and insightful post. I can't express enough how much I appreciate it.  As a novice, I'm currently trying to determine, if I did a sufficient job with the service of the 6497 (for a beginner), and if I didn't, how I can use the timing information to determine what I should fix/adjust/redo to achieve better results. What is the timing information telling me?  I'm sure the balance end cap stones aren't oiled as well as they should be. I can see that that is difficult to do by hand and will take many months of practice for me to get right. Oiling in general seems to be a art. Also, I don't currently have the equipment to adjust the jewels, adjust end shake etc.

Based on the ETA 6497-2 Manufacturing Information you provided, it seems like the watch is currently running within reason and within specifications.

As jdm mentioned, it's probably best to move on.

My ultimate goal is to be able to service and regulate the Seiko NH35A to chronometer specifications in 5-6 positions.  My current understanding is that Seiko makes some of the most reliable movements next to Rolex. Since I can obtain a full Invicta 8926OB used on EBay shipped for $50 on average, this seems like a good route to learn how to service, brush, polish and build watches.

I would appreciate  any additional advice you have on where I should focus my time to achieve my goals.  My current plan is to tear down and service the Seagul ST2100 (ETA 2836 clone) and then move on to servicing the Seiko NH35A repeatedly.

Again, thanks so much for taking time to respond to my post.

20200731_160413.jpg

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9 hours ago, caseten said:

My ultimate goal is to be able to service and regulate the Seiko NH35A to chronometer specifications in 5-6 positions. 

I don't want to discourage you from your goals but you may have some challenges with this one. In case you don't have the technical sheet I've attached it also the link to the rest of the tech sheets. At least with Seiko's OEM watches you do get more technical specs and specifications on timing. Unfortunately typically for timing these watches are not typically the best. although if you look at the list they actually lists some watches as being premium and their timing specifications such as the NE15 I'm currently looking at does have better timing specifications.

you'll never actually get true chronometer because the balance wheel and hairspring are not of chronometer grade. but nothing wrong with trying and having some fun. Fortunately it has the etachron system which improve slings and allows for greater range of regulation. Such as if the balance wheel should lose some of its weight? Statically poising the balance would help but you could also dynamically poise this would lighten the wheel little bit as long as you're careful and you should easily build a regulate that out. Then, watch sell better keep time in different positions.

 

 

https://www.timemodule.com/en/product-and-download.php?list=1

Seiko NH35_TG.pdf

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My rule of thumb is that you want to stay above and away from 220 as that's when the effects of balance poise errors get flipped and magnified. Your movement dipping in and out of 220 isn't doing it any favors in terms of positional consistency. 

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14 hours ago, JohnR725 said:

you'll never actually get true chronometer...

Never say never. 

Almost any half decent movement can be made to perform at "chronometer" specifications with enough effort. Whether or not it's worth the effort though is up to you.

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2 hours ago, CaptCalvin said:

Never say never. 

what you've done is very impressive and if you read what I had above I basically suggested this. But still does not make your watch a chronometer.

Wikipedia below lists the Swiss chronometer standards. As I stated above I am not sure that the general run-of-the-mill Seiko has a chronometer grade hairspring and or balance wheel. For instance if you look at ETA's manufacturing sheets for watches they'll list the specifications of the different grades. As soon as you go to the better or chronometer grade it's a different hairspring and balance wheel. conceivably than you may have a tough time passing timing specifications at the extreme temperatures that chronometers are supposed to run at.

what would be a fun test now is to pretend this is a Rolex and time it the way Rolex does. I'll have to get you a worksheet to fill out. The only catch is Rolex does not time at different temperatures so conceivably you could pass or equal a Rolex at least at room temperature.

then I didn't read every single technical word but in the past it was sad in that the only watches that can get Swiss chronometer status are Swiss watches. I think they've excluded other countries probably because they didn't want to look bad. To understand this look up what a grand Seiko is a beautiful timepiece that keeps beautiful time unfortunately does not have a beautiful affordable price like typical Seiko's would.

https://en.wikipedia.org/wiki/COSC

 

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5 hours ago, JohnR725 said:

Wikipedia below lists the Swiss chronometer standards. As I stated above I am not sure that the general run-of-the-mill Seiko has a chronometer grade hairspring and or balance wheel. For instance if you look at ETA's manufacturing sheets for watches they'll list the specifications of the different grades. As soon as you go to the better or chronometer grade it's a different hairspring and balance wheel. conceivably than you may have a tough time passing timing specifications at the extreme temperatures that chronometers are supposed to run at.

I have read the ISO 3159 criterion and I must say they are rather lax and probably developed when inferior material was still in wide use. If you look at either extremes of the requirements for temperature they aren't actually that extreme at all. The temperature range basically amounts to a moderately chilly Fall/Autumn day and a hot Summer day here in New York. Most alloys used in modern movements would perform to these standards with very little problems.

The actual practical advantages of the different alloys employed by ETA are nebulous at best. Nobody in the public knows the quantifiable value that these bring to the table. Outside of buzzwords ETA won't say by how much these actually help. It might just be marketing gimmick or give them just the slightest of edge when it comes to submitting mass produced movements for COSC certification. In a blind test I doubt anybody can with confidence tell the difference.

I have stated elsewhere that you can't call a movement "chronometer" unless it's been submitted for testing by an organization, but if you just want to make a movement that run at "chronometer" specs, it wouldn't take swapping parts and upgrading alloys to achieve in most cases with half decent modern movements.

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